APPLIED ANATOMY & PHYSIOLOGY-SEPTEMBER:-2019 (BKNMU)

⏩SECTION-I (ANATOMY)⏪

⏩Answer the following question (Any one) 15)

🔸a. Describe parts and location of small & large intestine with reference to surrounding structures.10

ANSWER:- The small and large intestines are two main components of the digestive system, each with distinct structures and functions. Here’s a brief description of their parts and locations with reference to surrounding structures:

Small Intestine:

1.Duodenum Location: The first part of the small intestine, located immediately after the stomach, and primarily resides in the upper abdomen.

Surrounding Structures: Adjacent to the pyloric sphincter of the stomach, pancreas, and liver (gallbladder and common bile duct).

2.Jejunum Location: The middle part of the small intestine, situated between the duodenum and ileum.

Surrounding Structures: Lies in the central abdomen, with no major surrounding structures apart from adjacent loops of intestine.

3.Ileum Location: The final part of the small intestine, extending from the jejunum to the cecum of the large intestine.

Surrounding Structures: Adjacent to the cecum (part of the large intestine) and the ileocecal valve, which controls the flow of contents between the small and large intestines.

Large Intestine (Colon):

1.Cecum Location: The beginning of the large intestine, located in the lower right abdomen.

Surrounding Structures: Adjacent to the ileum (end of the small intestine) and the appendix, a small pouch-like structure attached to the cecum.

2.Ascending Colon
Location: Ascends vertically from the cecum along the right side of the abdomen.

Surrounding Structures: Adjacent to the ileum, cecum, and liver.

3.Transverse Colon
Location: Travels horizontally across the upper abdomen from right to left.

Surrounding Structures: Adjacent to the liver, stomach, and small intestine.

4.Descending Colon
Location: Descends vertically along the left side of the abdomen.

Surrounding Structures: Adjacent to the spleen, left kidney, and small intestine.

5.Sigmoid Colon
Location: S-shaped segment that connects the descending colon to the rectum.

Surrounding Structures:
Adjacent to the bladder (in males) or uterus (in females), as well as the small intestine.

6.Rectum
Location: The final portion of the large intestine, terminating at the anus.

Surrounding Structures: Adjacent to the bladder (in males) or uterus (in females), as well as the anal sphincters.

Overall, the small intestine is primarily involved in digestion and nutrient absorption, while the large intestine is responsible for reabsorbing water and electrolytes, forming feces, and facilitating the elimination of waste from the body.

🔸b. List the different types of synovial joints with examples.05

ANSWER:- Synovial joints are characterized by the presence of a synovial cavity, which is filled with synovial fluid, allowing for smooth movement between the articulating surfaces. There are several types of synovial joints, each with unique structural characteristics and movement capabilities. Here are the different types of synovial joints along with examples:

1.Hinge Joint
Structure: One convex bone surface fits into a concave depression on another bone surface.

Movement: Primarily allows for flexion and extension.

Example: Elbow joint (ulna and humerus), knee joint (femur and tibia).

2.Ball-and-Socket Joint
Structure:
A rounded or ball-shaped end of one bone fits into a cup-shaped depression or socket of another bone.

Movement: Allows for movement in multiple directions, including flexion, extension, abduction, adduction, and rotation.

Example: Shoulder joint (glenohumeral joint), hip joint (coxofemoral joint).

3.Pivot Joint
Structure: A cylindrical or rounded bone rotates within a ring formed by another bone and a ligament.

Movement: Primarily allows for rotation around a central axis.

Example: Atlantoaxial joint (between the atlas and axis vertebrae), proximal radioulnar joint.

4.Condyloid Joint (Ellipsoidal Joint):
Structure: An oval-shaped condyle of one bone fits into an elliptical cavity of another bone.

Movement: Allows for flexion, extension, abduction, adduction, and circumduction.

Example: Radiocarpal joint (wrist joint), metacarpophalangeal joints (knuckle joints).

5.Saddle Joint
Structure: Each articulating surface has both concave and convex regions, resembling a saddle.

Movement: Allows for a wide range of movement, including flexion, extension, abduction, adduction, and circumduction.

Example: Carpometacarpal joint of the thumb (between the trapezium and first metacarpal bone).

6.Gliding Joint (Plane Joint):
Structure: Flat or slightly curved surfaces glide over each other.
Movement: B Allows for sliding or gliding movements in multiple directions.

Example: Intercarpal joints, intertarsal joints, articular processes between vertebrae.

⏩2 )🔸 a. Describe the structure and functions of heart and its position within thorax 10

ANSWER:- The heart is a muscular organ that functions as the central pump of the circulatory system, responsible for pumping oxygen-rich blood to the body’s tissues and organs. Here’s a description of the structure and functions of the heart, as well as its position within the thorax:

Structure of the Heart:

1.Chambers The heart has four chambers: two atria (right atrium and left atrium) and two ventricles (right ventricle and left ventricle).
Atria receive blood from the veins and pump it into the ventricles.
Ventricles pump blood out of the heart into the arteries.

2.Valves Valves within the heart ensure one-way flow of blood.
Atrioventricular valves (tricuspid valve and mitral valve) separate the atria from the ventricles.
Semilunar valves (pulmonary valve and aortic valve) separate the ventricles from the arteries.

3.Septa The heart is divided into left and right halves by a septum.
The interatrial septum separates the left and right atria, while the interventricular septum separates the left and right ventricles.

4.Blood Vessels Coronary arteries supply oxygenated blood to the heart muscle itself.
Coronary veins collect deoxygenated blood from the heart muscle and drain it into the right atrium.

Functions of the Heart:

1.Pumping Action The heart contracts rhythmically to pump blood throughout the body.
The right side of the heart pumps deoxygenated blood to the lungs for oxygenation, while the left side of the heart pumps oxygenated blood to the rest of the body.

2.Circulation
Systemic circulation: Oxygen-rich blood is pumped from the left ventricle through the aorta to the systemic arteries, delivering oxygen and nutrients to the body’s tissues and organs.

Pulmonary circulation: Deoxygenated blood is pumped from the right ventricle through the pulmonary arteries to the lungs, where it picks up oxygen and releases carbon dioxide before returning to the left atrium via the pulmonary veins.

3 Regulation of Blood Pressure: The heart adjusts its rate and force of contraction to regulate blood pressure and ensure adequate blood flow to meet the body’s metabolic demands.

Position of the Heart within the Thorax:

The heart is located in the mediastinum, the central compartment of the thorax between the lungs.

It lies slightly to the left of the midline of the chest, with about two-thirds of its mass to the left of the body’s midline.
The base of the heart (top) is directed upward and to the right, while the apex (bottom) points downward and to the left.
The heart is enclosed within the pericardial sac, a double-walled sac that protects and anchors the heart within the mediastinum.

🔸b. Structure of Larynx 05

ANSWER:- The larynx, also known as the voice box, is a complex structure located in the neck at the upper end of the trachea, just below the hyoid bone. It serves multiple functions, including sound production, protection of the airway, and facilitating the passage of air to and from the lungs. Here’s an overview of the structure of the larynx:

1.Cartilages
The larynx is composed of several cartilages, both hyaline and elastic, which provide structure and support. The major cartilages include:
Thyroid cartilage.
The largest cartilage, commonly referred to as the Adam’s apple, forms the anterior and lateral walls of the larynx.
Cricoid cartilage: A ring-shaped cartilage located inferior to the thyroid cartilage, serving as the base of the larynx and providing attachment for muscles and ligaments.
Epiglottis: A leaf-shaped elastic cartilage attached to the inner surface of the thyroid cartilage, which folds over the glottis during swallowing to prevent aspiration of food and liquids into the respiratory tract.
Arytenoid cartilages: Paired cartilages located on the superior surface of the cricoid cartilage, which articulate with the vocal cords and play a crucial role in sound production and vocal fold movement.

2.Vocal Cords
(Vocal Folds): The larynx contains two pairs of vocal cords, also known as vocal folds, which are composed of elastic tissue.
The true vocal cords are located within the laryngeal cavity and are involved in sound production by vibrating as air passes over them during exhalation.
The false vocal cords are located superior to the true vocal cords and play a role in protecting the airway during swallowing and coughing.

3.Muscles
The larynx is surrounded by intrinsic and extrinsic muscles that control its movements and functions.
Intrinsic muscles, such as the thyroarytenoid, cricothyroid, and posterior cricoarytenoid muscles, regulate the tension and position of the vocal cords, influencing pitch, volume, and sound quality.
Extrinsic muscles, including the suprahyoid and infrahyoid muscles, stabilize and position the larynx during swallowing, speaking, and breathing.

4.Ligaments:
Several ligaments within the larynx provide stability and support to the cartilaginous framework and vocal cords.
The vocal ligaments, located within the vocal folds, anchor the free edges of the vocal folds to the thyroid and arytenoid cartilages, allowing for controlled vibration during phonation.

5.Glottis
The glottis refers to the opening between the vocal cords within the larynx.
It regulates airflow through the larynx and plays a crucial role in sound production and phonation.

⏩Write short notes on: (Any three) 15

🔸1) Structure of middle ear

ANSWER:- The middle ear is a small, air-filled cavity located between the tympanic membrane (eardrum) and the inner ear. It consists of several structures that play important roles in transmitting sound vibrations from the outer ear to the inner ear. Here’s an overview of the structure of the middle ear:

1.Tympanic Membrane (Eardrum)
The tympanic membrane separates the external ear from the middle ear.
It consists of a thin, translucent membrane composed of three layers: an outer epithelial layer, a middle fibrous layer, and an inner mucosal layer.
The tympanic membrane vibrates in response to sound waves and transmits these vibrations to the ossicles of the middle ear.

2.Ossicles
The middle ear contains three small bones known as ossicles: the malleus (hammer), incus (anvil), and stapes (stirrup).
These ossicles form a chain of interconnected bones that transmit sound vibrations from the tympanic membrane to the inner ear.
The malleus is attached to the tympanic membrane and articulates with the incus, which in turn articulates with the stapes.
The stapes footplate rests against the oval window of the cochlea, transmitting sound vibrations to the fluid-filled inner ear.

3.Eustachian Tube (Auditory Tube)
The Eustachian tube connects the middle ear to the nasopharynx (the upper part of the throat behind the nasal cavity).
It serves to equalize air pressure between the middle ear and the atmosphere, helping to prevent discomfort or damage to the eardrum caused by pressure imbalances.
The Eustachian tube also facilitates the drainage of fluids from the middle ear into the throat, helping to maintain a clear middle ear space.

4.Middle Ear Muscles
The middle ear contains two small muscles: the tensor tympani and the stapedius.
The tensor tympani muscle attaches to the malleus and helps dampen sound vibrations by tensing the tympanic membrane.
The stapedius muscle attaches to the stapes and limits excessive movement of the ossicles in response to loud sounds, protecting the inner ear from damage.

5.Chorda Tympani Nerve
The chorda tympani nerve is a branch of the facial nerve (cranial nerve VII) that passes through the middle ear.
It carries taste sensation from the anterior two-thirds of the tongue and also provides parasympathetic innervation to the submandibular and sublingual salivary glands.

🔸2) Position & related structures of thyroid gland

ANSWER:- The thyroid gland is a butterfly-shaped endocrine gland located in the front of the neck, just below the larynx (voice box). It wraps around the front of the trachea (windpipe) and consists of two lobes connected by a narrow band of tissue called the isthmus. Here’s a description of the position of the thyroid gland and its related structures:

1.Location:

• The thyroid gland is situated in the anterior (front) aspect of the neck, below the thyroid cartilage (Adam’s apple) and above the suprasternal notch (the dip at the base of the neck).
• It extends from approximately the level of the fifth cervical vertebra (C5) to the first thoracic vertebra (T1), spanning the region between the thyroid cartilage and the sternum (breastbone).

2.Surrounding Structures:

• Trachea (Windpipe): The thyroid gland lies anterior to the trachea, with the tracheal rings providing support to the gland.
• Esophagus: The thyroid gland is located posterior to the esophagus, separated by the pretracheal fascia.
• Inferior Thyroid Artery: The inferior thyroid artery, a branch of the thyrocervical trunk, supplies blood to the thyroid gland.
• Recurrent Laryngeal Nerves: The recurrent laryngeal nerves, branches of the vagus nerve (cranial nerve X), pass in close proximity to the thyroid gland. These nerves supply motor innervation to the muscles of the larynx (voice box) and are at risk of injury during thyroid surgery.

3.Isthmus The isthmus of the thyroid gland connects the two lobes of the gland across the midline of the neck.
It typically lies anterior to the second to fourth tracheal rings and may vary in size and shape among individuals.

4.Pyramidal Lobe In some individuals, a small, conical extension of thyroid tissue known as the pyramidal lobe may extend superiorly from the isthmus toward the hyoid bone.
The presence and size of the pyramidal lobe can vary and are considered anatomical variations rather than abnormalities.

🔸3) Types of epithelial tissue with their function

ANSWER:- Epithelial tissue is one of the four primary types of tissue, and it covers the body’s surfaces, lines internal cavities and organs, and forms glands. Epithelial tissues are classified based on their structure and function. Here are the main types of epithelial tissue along with their functions:

1.Simple Squamous Epithelium
Structure: Single layer of flattened cells with sparse cytoplasm and centrally located nuclei.
Function: Facilitates diffusion and filtration. Found in areas where rapid diffusion or filtration occurs, such as the alveoli of the lungs (for gas exchange), lining of blood vessels (endothelium), and serous membranes (mesothelium).

2.Simple Cuboidal Epithelium
Structure: Single layer of cube-shaped cells with centrally located nuclei.
Function: Secretion and absorption. Found in kidney tubules (for secretion and reabsorption), ducts of glands (for secretion), and surface of the ovaries.

3.Simple Columnar Epithelium
Structure: Single layer of tall, column-shaped cells with elongated nuclei located near the basement membrane.
Function: Absorption, secretion, and protection. Found in the lining of the gastrointestinal tract (for absorption and secretion), gallbladder, and some regions of the respiratory tract.

4.Pseudostratified Columnar Epithelium
Structure: Single layer of cells of varying heights, giving the appearance of stratification. Nuclei are located at different levels, giving a pseudostratified appearance.
Function: Secretion and propulsion of mucus by ciliary action. Found in the respiratory tract (trachea and bronchi) and portions of the male reproductive tract (epididymis).

5.Stratified Squamous Epithelium
Structure: Multiple layers of flattened cells. Basal layers are cuboidal or columnar, while apical layers are squamous.
Function: Protection against abrasion, pathogens, and chemical attack. Found in the skin (epidermis), oral cavity, esophagus, and vagina.

6.Stratified Cuboidal Epithelium
Structure: Multiple layers of cube-shaped cells.
Function: Protection and limited secretion and absorption. Found in sweat glands, mammary glands, and salivary gland ducts.

7.Stratified Columnar Epithelium
Structure: Multiple layers of tall, column-shaped cells.
Function: Protection and secretion. Found in the male urethra and portions of the pharynx.

8.Transitional Epithelium
Structure: Stratified epithelium with variable appearance. Basal layers are cuboidal or columnar, while apical layers are dome-shaped or squamous when stretched.
Function: Allows for stretching and distension. Found in the urinary bladder, ureters, and renal pelvis.

🔸4) Compare and contrast structure & function of lymph node with that of spleen

ANSWER:- compare and contrast the structure and function of lymph nodes with that of the spleen:

Structure:

Lymph Nodes:
1.Size and Shape Lymph nodes are small, bean-shaped organs ranging from a few millimeters to about 1-2 centimeters in size.

2.Composition Lymph nodes are encapsulated structures composed of connective tissue containing lymphoid nodules and sinuses.

3.Internal Structure Internally, lymph nodes consist of compartments called cortical and medullary regions. The cortex contains lymphoid nodules (follicles) with germinal centers, while the medulla contains lymphocytes, macrophages, and plasma cells.

4.Afferent and Efferent Vessels Lymph nodes receive lymphatic vessels (afferent lymphatic vessels) that bring lymph containing antigens and immune cells. They also have efferent lymphatic vessels that drain filtered lymph.

5.Location Lymph nodes are distributed throughout the body, with clusters found in regions such as the neck, armpits, and groin.

Spleen:
1.Size and Shape The spleen is a larger, elongated organ located in the upper left quadrant of the abdomen, measuring about 12-14 centimeters in length.

2.Composition The spleen consists of red pulp and white pulp. The red pulp contains blood-filled sinuses and macrophages, while the white pulp contains lymphoid tissue with lymphocytes and antigen-presenting cells.

3.Internal Structure The white pulp of the spleen forms discrete areas called splenic nodules or Malpighian corpuscles, surrounded by red pulp. The red pulp contains splenic cords (cords of Billroth) composed of reticular fibers and cells.

4.Blood Supply The spleen receives blood from the splenic artery, which branches into smaller arterioles that lead to the red pulp. Blood leaves the spleen via the splenic vein.

5.Function The spleen functions as a filter for blood, removing old or damaged red blood cells, as well as a reservoir for platelets and immune responses to blood-borne pathogens.

Function:

Lymph Nodes:
1.Filtration Lymph nodes filter lymph and remove foreign particles, including pathogens and antigens.

2.Immune Response
Lymph nodes serve as sites for antigen presentation, lymphocyte activation, and the initiation of adaptive immune responses.

Spleen:
1.Blood Filtration The spleen filters blood, removing old or damaged red blood cells and pathogens.

2.Hematopoiesis: In fetal life and certain pathological conditions, the spleen can serve as a site of hematopoiesis (blood cell production).

3.Immune Response The spleen contains lymphoid tissue where immune responses to blood-borne pathogens are initiated. It also produces antibodies and filters antigens from the blood.

🔸5) Structure of skin

ANSWER:- The skin is the largest organ of the human body, serving as a protective barrier between the internal organs and the external environment. It consists of three main layers, each with distinct structures and functions. Here’s an overview of the structure of the skin:

Epidermis: The epidermis is the outermost layer of the skin, consisting mainly of stratified squamous epithelial tissue.

Layers of the Epidermis
1.Stratum Corneum The outermost layer, composed of dead, flattened keratinocytes that are continuously shed and replaced.
2.Stratum Lucidum Present only in thick skin (e.g., palms and soles), consisting of clear, flattened cells with no distinct nuclei.
3.Stratum Granulosum Contains keratinocytes that are actively producing keratin and keratohyalin granules, contributing to the waterproofing of the skin.
4.Stratum Spinosum Consists of several layers of polygonal keratinocytes connected by desmosomes, providing strength and flexibility to the skin.
5.Stratum Basale (Stratum Germinativum)
The deepest layer, composed of a single layer of basal cells (stem cells) that undergo rapid cell division to replenish the upper layers. Also contains melanocytes, which produce the pigment melanin.

2. Dermis: The dermis is the middle layer of the skin, composed mainly of dense irregular connective tissue.
   Structures in the Dermis
   1.Papillary Layer
   Consists of loose connective tissue containing papillae that project into the epidermis. Contains blood vessels, nerve endings, and Meissner’s corpuscles (touch receptors).
   2.Reticular Layer
   Deeper layer composed of dense irregular connective tissue with collagen and elastic fibers. Contains blood vessels, hair follicles, sebaceous glands, sweat glands, and Pacinian corpuscles (pressure receptors).
3. Hypodermis (Subcutaneous Tissue): The hypodermis is the deepest layer of the skin, composed mainly of adipose (fat) tissue and loose connective tissue.
   Functions to insulate the body, store energy, and anchor the skin to underlying structures such as muscles and bones. Additional Structures:

Hair Follicles Epidermal invaginations that extend into the dermis and produce hair.

Sebaceous GlandsGlands associated with hair follicles that secrete sebum (oil) to lubricate the skin and hair.

Sweat Glands (Eccrine and Apocrine) Glands that produce sweat to regulate body temperature and excrete waste products.

Blood Vessels Provide nutrients and oxygen to the skin and help regulate body temperature.

Nerves Transmit sensory information such as touch, temperature, and pain.

Melanocytes Cells in the epidermis that produce the pigment melanin, which helps protect against UV radiation and determines skin color.

⏩Answer the following questions (Any four) 08

🔸1) Structure of neuron

ANSWER:- Neurons, also known as nerve cells, are the fundamental units of the nervous system, responsible for transmitting electrical and chemical signals throughout the body. Here’s an overview of the structure of a typical neuron:

1.Cell Body (Soma): The cell body is the main part of the neuron, containing the nucleus and organelles essential for cell function. Nucleus
Contains the genetic material (DNA) of the neuron, governing its structure and function.

Organelles
Include structures such as the endoplasmic reticulum, Golgi apparatus, mitochondria, and ribosomes, which are involved in protein synthesis, energy production, and cellular metabolism.

2.Dendrites: Dendrites are short, branching extensions of the cell body that receive incoming signals (chemical and electrical) from other neurons or sensory receptors.

Dendritic Spines
Small protrusions on dendrites that increase the surface area for synaptic connections and facilitate communication with other neurons.

3.Axon: The axon is a long, slender projection of the neuron that conducts electrical impulses away from the cell body to other neurons, muscles, or glands.

Axon Hillock The region where the axon originates from the cell body, responsible for generating action potentials.

Myelin Sheath Some axons are insulated by a fatty substance called myelin, produced by specialized glial cells called oligodendrocytes in the central nervous system (CNS) and Schwann cells in the peripheral nervous system (PNS). Myelin sheaths increase the speed and efficiency of signal transmission along the axon.

Nodes of Ranvier Gaps in the myelin sheath along the axon where action potentials are regenerated, allowing for rapid conduction of nerve impulses.

Axon Terminals (Axon Endings)
Branched terminations of the axon that form synaptic connections with other neurons or target cells.

4 .Synapses: Synapses are specialized junctions between neurons or between neurons and target cells (such as muscles or glands), where communication occurs.

Presynaptic Neuron The neuron sending the signal.

Postsynaptic Neuron The neuron receiving the signal.

Synaptic Cleft The narrow gap between the presynaptic and postsynaptic neurons, across which neurotransmitters are released.

Neurotransmitters Chemical messengers released by the presynaptic neuron that bind to receptors on the postsynaptic neuron, initiating a response.

Additional Structures:

Supporting Cells (Neuroglia or Glial Cells)
Non-neuronal cells that provide structural support, insulation, and nourishment to neurons. Examples include astrocytes, oligodendrocytes, Schwann cells, and microglia.

Neurons are highly specialized cells with unique structures adapted for receiving, processing, and transmitting signals within the nervous system. Their complex architecture and functional properties enable the intricate communication network that underlies all neurological processes, including sensory perception, motor control, cognition, and behavior.

🔸2) Cells of connective tissue

ANSWER:- Connective tissue is a diverse group of tissues that provide support, structure, and insulation to the body’s organs and structures. Several types of cells are found within connective tissue, each with specific functions. Here are the main cells of connective tissue:

1.Fibroblasts
Fibroblasts are the most abundant cells in connective tissue.
They produce and maintain the extracellular matrix, including collagen, elastin, and other fibers, which provide structural support and resilience to the tissue.
Fibroblasts also play a role in wound healing by synthesizing new extracellular matrix components.

2.Adipocytes (Fat Cells)
Adipocytes are specialized cells that store energy in the form of triglycerides (fat).
They are found in adipose tissue throughout the body and can vary in size and number depending on nutritional status and metabolic demands.
Adipocytes also secrete hormones and cytokines that regulate metabolism, inflammation, and immune function.

3.Mast Cells
Mast cells are immune cells that play a role in inflammation and allergic reactions.
They contain granules filled with inflammatory mediators such as histamine, which are released in response to injury, infection, or allergens.
Mast cells also contribute to tissue repair and remodeling.

4.Macrophages
Macrophages are immune cells that engulf and digest cellular debris, pathogens, and foreign substances through a process called phagocytosis.
They also play a role in immune defense by presenting antigens to other immune cells and secreting cytokines that regulate inflammation and immune responses.
Tissue-resident macrophages have specialized names depending on their location, such as Kupffer cells in the liver and microglia in the central nervous system.

5.Plasma Cells
Plasma cells are derived from B lymphocytes and produce antibodies (immunoglobulins) in response to pathogens or foreign antigens.
Antibodies bind to specific targets, such as viruses or bacteria, marking them for destruction by immune cells or neutralizing their activity.

6.Chondrocytes
Chondrocytes are the primary cells found in cartilage, a type of connective tissue that provides support and cushioning to joints and other structures.
They produce and maintain the extracellular matrix of cartilage, including collagen and proteoglycans, which give cartilage its unique properties.

7.Osteoblasts and Osteocytes
Osteoblasts are bone-forming cells responsible for synthesizing and mineralizing the extracellular matrix of bone tissue.
Osteocytes are mature bone cells derived from osteoblasts that are embedded within the bone matrix and maintain bone tissue integrity.

🔸3) Types and function of muscle tissue

ANSWER:- Muscle tissue is a specialized type of tissue composed of cells called muscle fibers or myocytes that have the ability to contract, producing force and movement. There are three main types of muscle tissue in the human body, each with unique structures and functions:

1.Skeletal Muscle Tissue

Structure
Skeletal muscle tissue is composed of long, multinucleated muscle fibers arranged in parallel bundles called fascicles. Each muscle fiber contains myofibrils, which are composed of repeating units called sarcomeres.

Function
Skeletal muscle tissue is responsible for voluntary movements of the body, including locomotion, manipulation of objects, and facial expressions. It also plays a role in maintaining posture and stabilizing joints.

2.Cardiac Muscle Tissue

Structure
Cardiac muscle tissue is found exclusively in the heart and is composed of branched, striated muscle fibers called cardiomyocytes. These cells are interconnected by intercalated discs, which contain gap junctions and desmosomes.

Function
Cardiac muscle tissue contracts rhythmically to pump blood throughout the body. It generates and conducts electrical impulses that coordinate heartbeats, ensuring efficient and coordinated pumping action.

3.Smooth Muscle Tissue

Structure
Smooth muscle tissue is found in the walls of hollow organs, blood vessels, and other internal structures. It consists of elongated, spindle-shaped cells with a single nucleus and lacks striations.

Function
Smooth muscle tissue is responsible for involuntary movements, such as peristalsis (wave-like contractions) in the digestive tract, constriction and dilation of blood vessels to regulate blood flow and pressure, and contraction of the bladder during urination.

Summary of Functions:

Skeletal Muscle
Voluntary movement, posture, stabilization of joints.
Cardiac Muscle
Involuntary rhythmic contraction, pumping of blood throughout the body.
Smooth Muscle
Involuntary contraction of hollow organs, blood vessels, and other structures, regulation of blood flow and pressure, peristalsis, and other visceral functions.

Each type of muscle tissue has unique structural and functional properties adapted to its specific roles in the body, collectively allowing for coordinated movement, circulation, and physiological processes essential for life.

🔸4) Principle bones of appendicular skeleton

ANSWER:- 1.Pectoral Girdle (Shoulder Girdle)
Clavicle (Collarbone)
A slender bone that connects the sternum (breastbone) to the scapula (shoulder blade). It helps to stabilize the shoulder joint and provides attachment for muscles of the upper limb.

Scapula (Shoulder Blade)
A flat, triangular bone that lies on the posterior aspect of the thoracic cage. It articulates with the clavicle and the humerus (upper arm bone) and provides attachment for muscles involved in shoulder movement.

2.Upper Limb (Arm)
Humerus
The long bone of the upper arm, extending from the shoulder to the elbow. It articulates with the scapula at the shoulder joint and with the radius and ulna at the elbow joint.

Radius
The lateral bone of the forearm, located on the thumb side. It articulates with the humerus and the ulna, allowing for rotation of the forearm (pronation and supination).

Ulna
The medial bone of the forearm, located on the pinky side. It articulates with the humerus and the radius, providing stability to the forearm and allowing for bending and straightening of the arm.

3.Carpal Bones (Wrist)
The carpal bones are a group of eight small bones arranged in two rows. They articulate with the radius and ulna proximally and with the metacarpal bones distally, forming the wrist joint.

4.Metacarpal Bones (Hand)
There are five metacarpal bones in the palm of the hand, numbered from the thumb (first) to the pinky (fifth). They articulate proximally with the carpals and distally with the phalanges.

5.Phalanges (Fingers)
Each finger has three phalanges (proximal, middle, and distal), except for the thumb, which has two. The fingers and thumb collectively have 14 phalanges.

6.Pelvic Girdle
Ilium
The largest and most superior bone of the pelvis. It articulates with the sacrum posteriorly and forms the hip joint with the femur.

Ischium
The inferior and posterior portion of the hip bone. It supports the body when sitting and forms the lower, posterior portion of the acetabulum (hip socket).

Pubis
The anterior portion of the hip bone, forming the front of the pelvis. It articulates with the opposite pubis at the pubic symphysis.

7.Lower Limb (Leg)
Femur
The longest and strongest bone in the body, extending from the hip to the knee. It articulates with the pelvis at the hip joint and with the tibia and patella at the knee joint.

Patella (Kneecap)
A flat, triangular bone located in front of the knee joint. It articulates with the femur and protects the knee joint.
Tibia
The larger, medial bone of the lower leg, commonly known as the shinbone. It articulates with the femur, fibula, and talus, providing support and stability to the leg.

Fibula
The smaller, lateral bone of the lower leg. It provides attachment for muscles and ligaments and stabilizes the ankle joint.

8.Tarsal Bones (Ankle)
The tarsal bones are a group of seven bones that make up the ankle and proximal portion of the foot. They articulate with the tibia and fibula proximally and with the metatarsal bones distally.

9.Metatarsal Bones (Foot)
There are five metatarsal bones in the sole of the foot, numbered from the big toe (first) to the little toe (fifth). They articulate proximally with the tarsal bones and distally with the phalanges.

10.Phalanges (Toes)
Each toe has three phalanges (proximal, middle, and distal), except for the big toe, which has two. The toes collectively have 14 phalanges.

These are the principal bones of the appendicular skeleton, which collectively provide support, mobility, and protection to the body’s limbs and facilitate various movements and activities.

🔸5) Gross structure of lungs

ANSWER:- The lungs are the primary organs of the respiratory system, responsible for the exchange of oxygen and carbon dioxide between the air and the bloodstream. Here’s an overview of the gross structure of the lungs:

1. Lobes:
   Each lung is divided into lobes, with the right lung having three lobes (upper, middle, and lower) and the left lung having two lobes (upper and lower).

The lobes are separated by fissures: the right lung has both horizontal and oblique fissures, while the left lung has only an oblique fissure.

2. Surfaces:
   The lungs have three surfaces: 1.Costal Surface
   Adjacent to the ribs. 2.Mediastinal Surface
   Faces the mediastinum, where the heart and other thoracic structures are located. 3.Diaphragmatic Surface
   Rests on the diaphragm.
3. Apex and Base:
   The apex of the lung is the superior portion that extends above the first rib into the neck.
   The base of the lung is the inferior portion that rests on the diaphragm.
4. Hilum:
   The hilum (or root) of the lung is a region on the mediastinal surface where structures such as the bronchi, pulmonary vessels, lymphatic vessels, and nerves enter and exit the lung.
   The bronchi enter the lung at the hilum and branch into smaller bronchioles within the lung tissue.
5. Bronchial Tree: The bronchial tree consists of the bronchi and their branches within the lungs. The main bronchi (right and left) branch into smaller secondary bronchi, which further divide into tertiary bronchi and bronchioles. Bronchioles eventually lead to alveolar ducts and alveoli, where gas exchange occurs.
6. Alveoli:
   Alveoli are tiny air sacs clustered at the ends of bronchioles.
   They are the sites of gas exchange, where oxygen from the air diffuses into the bloodstream and carbon dioxide diffuses out of the bloodstream into the air.
7. Pleura:
   The lungs are surrounded by a double-layered membrane called the pleura
   The visceral pleura covers the outer surface of the lungs, while the parietal pleura lines the inner surface of the thoracic cavity. The pleural space between the two layers contains a small amount of lubricating fluid, allowing for smooth movement during breathing.

The gross structure of the lungs includes lobes, surfaces, apex, base, hilum, bronchial tree, alveoli, and pleura. These structures work together to facilitate the exchange of gases and maintain proper respiratory function in the body.

🔸6) Define exocrine & endocrine glands.

ANSWER:- Exocrine and endocrine glands are two types of glands in the human body that secrete substances with distinct modes of action and distribution:

1.Exocrine Glands
Exocrine glands secrete their products into ducts, which then carry the secretions to specific locations within the body or to its surface.
Examples of exocrine glands include sweat glands, salivary glands, sebaceous glands (oil glands), and mammary glands.
The secretions produced by exocrine glands may serve various functions, such as lubricating, cooling, protecting, or digesting substances in the body.
Exocrine glands are typically composed of epithelial tissue and may have a tubular or alveolar structure, depending on their function.

2.Endocrine Glands
Endocrine glands secrete their products (hormones) directly into the bloodstream, rather than through ducts, to reach target cells or organs located throughout the body.
Hormones are chemical messengers that regulate various physiological processes, including metabolism, growth and development, reproduction, and stress response.
Examples of endocrine glands include the pituitary gland, thyroid gland, adrenal glands, pancreas, and gonads (testes and ovaries).
Endocrine glands are often composed of specialized epithelial cells organized into clusters or cords, surrounded by a rich network of blood vessels to facilitate hormone secretion into the bloodstream.

⏩SECTION-II (PHYSIOLOGY)⏪

⏩Answer the following question (Any one) 10

🔸1) Describe steps of transmission of impulse across neuromuscular Junction

ANSWER:-The transmission of an impulse across a neuromuscular junction involves a series of steps that ultimately lead to muscle contraction. Here’s a description of these steps:

Action Potential Generation in Motor Neuron:

• The process begins when an action potential (electrical signal) travels down the axon of a motor neuron towards the neuromuscular junction (NMJ).

Release of Acetylcholine (ACh):

• When the action potential reaches the axon terminal of the motor neuron, it triggers the opening of voltage-gated calcium channels.
• Calcium ions (Ca^2+) enter the axon terminal, causing synaptic vesicles containing the neurotransmitter acetylcholine (ACh) to fuse with the presynaptic membrane.
• ACh is released into the synaptic cleft (the space between the motor neuron and the muscle fiber).

Binding of ACh to Receptors on Muscle Fiber:

• ACh diffuses across the synaptic cleft and binds to nicotinic acetylcholine receptors (nAChRs) located on the motor end plate (sarcolemma) of the muscle fiber.
• This binding causes nAChRs to undergo a conformational change, leading to the opening of ion channels in the sarcolemma.

Generation of End Plate Potential (EPP):

• The opening of ion channels allows sodium ions (Na^+) to enter the muscle fiber, while potassium ions (K^+) exit, resulting in a local depolarization of the sarcolemma.
• This depolarization is known as the end plate potential (EPP), which spreads along the sarcolemma and into the muscle fiber via voltage-gated sodium channels.

Propagation of Action Potential in Muscle Fiber:

• If the EPP is of sufficient magnitude to reach the threshold potential, it triggers the opening of voltage-gated sodium channels along the sarcolemma.
• This initiates an action potential that propagates along the sarcolemma and into the T-tubules (transverse tubules), which are invaginations of the sarcolemma that penetrate into the interior of the muscle fiber.

Release of Calcium Ions from Sarcoplasmic Reticulum:

• The action potential traveling along the T-tubules stimulates voltage-gated calcium channels in the sarcoplasmic reticulum (SR) membrane to open.
• Calcium ions (Ca^2+) stored within the SR are released into the cytoplasm of the muscle fiber.

Initiation of Muscle Contraction:

• Calcium ions bind to troponin molecules on the actin filaments within the muscle fiber.
• This binding causes a conformational change in the troponin-tropomyosin complex, exposing myosin-binding sites on the actin filaments.
  Myosin heads (cross-bridges) bind to these exposed sites, forming cross-bridges between actin and myosin, and initiating muscle contraction (sliding filament mechanism).

8.Termination of Signal Transmission
The action of acetylcholinesterase (AChE) rapidly breaks down acetylcholine (ACh) in the synaptic cleft into acetic acid and choline.
This enzymatic degradation of ACh prevents continuous stimulation of the muscle fiber, allowing for relaxation and termination of the muscle contraction cycle.

This sequence of events represents the fundamental process by which a motor neuron signal is transmitted across the neuromuscular junction to elicit muscle contraction.

🔸2) Name 13 Coagulation factors. Describe extrinsic Pathway of Coagulation

ANSWER:- The coagulation process involves a cascade of enzymatic reactions that lead to the formation of a stable blood clot. There are thirteen coagulation factors involved in this process, numbered using Roman numerals. Here are the names of the thirteen coagulation factors:

1. Factor I – Fibrinogen
2. Factor II – Prothrombin
3. Factor III – Tissue Factor (also known as Thromboplastin)
4. Factor IV – Calcium ions (Ca^2+)
5. Factor V – Labile factor (Proaccelerin)
6. Factor VI – Accelerin
7. Factor VII – Stable factor (Proconvertin)
8. Factor VIII – Antihemophilic factor (AHF)
9. Factor IX – Christmas factor (Plasma thromboplastin component or PTC)
10. Factor X – Stuart-Prower factor
11. Factor XI – Plasma thromboplastin antecedent (PTA)
12. Factor XII – Hageman factor (Glass factor)
13. Factor XIII – Fibrin-stabilizing factor (FSF)

Now, let’s describe the extrinsic pathway of coagulation:

Extrinsic Pathway of Coagulation:

1.Initiation The extrinsic pathway is triggered by external trauma or injury that exposes tissue factor (TF), also known as tissue thromboplastin, to the bloodstream.
TF is a membrane-bound protein present in subendothelial cells and tissue cells outside blood vessels.

2.Activation of Factor VII Tissue factor (TF) binds to and activates Factor VII (Factor VIIa).
The TF-Factor VIIa complex forms a catalytic complex that initiates the coagulation cascade.

3.Activation of Factor X
The TF-Factor VIIa complex activates Factor X (Factor Xa) by proteolytic cleavage.
This activation occurs in the presence of calcium ions (Factor IV).

4.Formation of Prothrombinase Complex
Factor Xa, along with Factor Va (activated by the intrinsic pathway or present in plasma), forms the prothrombinase complex on the surface of activated platelets.
The prothrombinase complex catalyzes the conversion of prothrombin (Factor II) into thrombin (Factor IIa).

5.Thrombin Generation
Thrombin is a key enzyme in the coagulation cascade and has multiple functions, including the conversion of fibrinogen (Factor I) into fibrin strands.
Fibrin strands form a meshwork that stabilizes the blood clot and traps blood cells to form a stable clot.

6.Fibrin Clot Formation
Thrombin cleaves fibrinogen to fibrin monomers, which polymerize to form insoluble fibrin strands.
Fibrin strands aggregate and crosslink to form a fibrin clot, stabilizing the platelet plug and sealing the site of injury.

The extrinsic pathway of coagulation plays a crucial role in the rapid initiation of clot formation in response to tissue injury, helping to prevent excessive bleeding and promote wound healing.

⏩Write short notes on: (Any three) 15

🔸1) Transport of Oxygen

ANSWER:- The transport of oxygen in the human body primarily occurs through the bloodstream, facilitated by the protein hemoglobin within red blood cells (erythrocytes). Here’s how oxygen is transported from the lungs to tissues throughout the body:

1.Diffusion in the Lungs
Oxygen is inhaled into the lungs and diffuses across the respiratory membrane into the bloodstream.
Oxygen molecules move from an area of high partial pressure in the alveoli (air sacs) to an area of lower partial pressure in the pulmonary capillaries.

2.Binding to Hemoglobin
Once in the bloodstream, oxygen binds reversibly to hemoglobin molecules within red blood cells, forming oxyhemoglobin.
Hemoglobin is a globular protein with four subunits, each containing an iron ion (Fe^2+) that can bind to one molecule of oxygen.
Each hemoglobin molecule can carry up to four molecules of oxygen, allowing for efficient transport.

3.Oxygen Transport
Oxygen-rich blood flows from the lungs through the pulmonary veins to the left side of the heart.
The heart pumps oxygenated blood into the systemic circulation, delivering oxygen to tissues throughout the body via arteries and arterioles.
As blood travels through the systemic capillaries, oxygen is released from hemoglobin and diffuses into surrounding tissues, where it is used for cellular respiration.

4.Loading and Unloading of Oxygen
Oxygen binds to hemoglobin in the lungs, where the partial pressure of oxygen is high (loading).
In tissues, where oxygen is actively metabolized by cells, the partial pressure of oxygen is lower, causing hemoglobin to release oxygen molecules (unloading).

5.Bohr Effect
Factors such as pH, temperature, and carbon dioxide concentration affect the affinity of hemoglobin for oxygen.
The Bohr effect describes how an increase in acidity (decrease in pH) or an increase in carbon dioxide concentration promotes the release of oxygen from hemoglobin, enhancing oxygen unloading in metabolically active tissues.

6.Carbon Dioxide Transport
In addition to oxygen, carbon dioxide produced by cellular metabolism is transported in the bloodstream.
Most carbon dioxide is transported in the form of bicarbonate ions (HCO3^-), which are produced by the hydration of carbon dioxide and transported in plasma.
Some carbon dioxide binds directly to hemoglobin or is transported as dissolved gas in the plasma.

Overall, the transport of oxygen in the bloodstream ensures that oxygen is efficiently delivered to tissues throughout the body, supporting cellular metabolism and physiological functions.

🔸2) Factors affecting Blood Pressure

ANSWER:- Blood pressure is influenced by various factors, including physiological, environmental, and lifestyle factors. Here are some of the key factors that can affect blood pressure:

1.Cardiac Output
Cardiac output refers to the amount of blood pumped by the heart per minute.
An increase in cardiac output leads to an increase in blood pressure, as more blood is being circulated throughout the body.

2.Peripheral Resistance
Peripheral resistance refers to the resistance encountered by blood flow in the arteries.
Narrowing of the arteries, caused by factors such as vasoconstriction or arterial stiffness, increases peripheral resistance and elevates blood pressure.

3.Blood Volume
Blood volume refers to the total volume of blood circulating in the body.
An increase in blood volume, due to factors such as fluid retention or excessive salt intake, can lead to an increase in blood pressure.

4.Viscosity of Blood
Blood viscosity refers to the thickness or stickiness of blood.
An increase in blood viscosity, often associated with conditions such as dehydration or polycythemia (increased red blood cell count), can lead to higher blood pressure.

5.Hormonal Regulation
Hormones such as adrenaline (epinephrine), aldosterone, and antidiuretic hormone (ADH) play a role in regulating blood pressure.
Adrenaline increases heart rate and constricts blood vessels, leading to temporary increases in blood pressure.
Aldosterone promotes sodium retention by the kidneys, which can increase blood volume and blood pressure.
ADH regulates water reabsorption by the kidneys, influencing blood volume and blood pressure.

6.Autonomic Nervous System Activity
The autonomic nervous system (ANS) regulates involuntary functions such as heart rate and blood vessel tone.
Sympathetic nervous system activation increases heart rate and constricts blood vessels, leading to higher blood pressure.
Parasympathetic nervous system activation has the opposite effect, causing vasodilation and lowering blood pressure.

7.Age
Blood pressure tends to increase with age due to factors such as arterial stiffness and changes in blood vessel structure.
Older adults are more likely to have higher blood pressure compared to younger individuals.

8.Physical Activity
Regular physical activity is associated with lower blood pressure levels.
Exercise helps to improve cardiovascular health, reduce peripheral resistance, and promote vasodilation, leading to lower blood pressure over time.

9.Dietary Factors
High sodium intake can increase blood pressure by promoting fluid retention and vasoconstriction.
A diet rich in fruits, vegetables, whole grains, and low-fat dairy products, known as the Dietary Approaches to Stop Hypertension (DASH) diet, is associated with lower blood pressure levels.

10.Stress
Acute or chronic stress can temporarily elevate blood pressure through activation of the sympathetic nervous system and release of stress hormones.
Chronic stress can also contribute to unhealthy coping behaviors, such as overeating or smoking, which can further increase blood pressure.

Understanding these factors can help individuals make lifestyle modifications and seek appropriate medical interventions to manage blood pressure and reduce the risk of hypertension-related complications.

🔸3) Micturition reflex

ANSWER:-The micturition reflex, also known as the urination reflex, is a complex neurological process that controls the emptying of the urinary bladder. It involves coordinated actions of the urinary bladder, spinal cord, and brain to initiate and regulate the process of urination. Here’s an overview of the micturition reflex:

1.Bladder Filling
As urine is produced by the kidneys, it accumulates in the urinary bladder.
The bladder walls stretch to accommodate the increasing volume of urine without a significant increase in pressure due to the elasticity of the bladder tissue.

2.Activation of Stretch Receptors
As the bladder fills, stretch receptors in the bladder wall are activated in response to the increased tension/stretching of the bladder wall.
These stretch receptors send sensory nerve impulses to the spinal cord, signaling the degree of bladder distension.

3.Transmission to Spinal Cord
Sensory nerve fibers carrying signals from the stretch receptors travel through the pelvic nerves to the sacral region of the spinal cord.
In the spinal cord, these sensory signals are relayed to interneurons in the sacral micturition center, located in the spinal cord segments S2 to S4.

4.Reflex Activation
The sacral micturition center integrates sensory input from the bladder stretch receptors and coordinates motor responses involved in urination.
Excitatory signals from the sacral micturition center cause the detrusor muscle (smooth muscle layer of the bladder wall) to contract and the internal urethral sphincter to relax.
Simultaneously, inhibitory signals are sent to the external urethral sphincter (voluntary sphincter) to relax, allowing for the flow of urine out of the bladder.

5.Conscious Control
While the micturition reflex can occur involuntarily in response to bladder distension, voluntary control of urination is also possible through higher brain centers.
The pontine micturition center, located in the brainstem, receives input from the sacral micturition center and can override or facilitate the reflexive bladder emptying process.
Voluntary control of urination involves the conscious relaxation or contraction of the external urethral sphincter to initiate or suppress urination as needed.

6.Urination
When the bladder contracts and the urethral sphincters relax, urine is expelled from the bladder through the urethra and out of the body.
The process of urination is typically accompanied by sensations of bladder fullness and the conscious decision to initiate voiding.

The micturition reflex ensures timely and coordinated emptying of the urinary bladder, maintaining appropriate urinary continence and preventing bladder overdistension. It involves both involuntary and voluntary components, allowing for efficient control of the urination process.

🔸4) Secretions from Anterior and Posterior Pituitary

ANSWER:- The anterior and posterior pituitary are two distinct parts of the pituitary gland, each responsible for producing and releasing different hormones that regulate various physiological processes in the body. Here are the secretions from the anterior and posterior pituitary:

Anterior Pituitary (Adenohypophysis):
The anterior pituitary produces and releases several hormones in response to releasing and inhibiting hormones secreted by the hypothalamus.

These hormones include:

1.Growth Hormone (GH)
Growth hormone stimulates growth, cell reproduction, and regeneration in humans and other animals.
It plays a crucial role in childhood growth and development, as well as maintaining tissue and organ health throughout life.

2.Prolactin (PRL)
Prolactin stimulates milk production (lactation) in the mammary glands of the breast, primarily in females after childbirth.
It also has roles in reproductive function, metabolism, and immune regulation.

3.Thyroid-Stimulating Hormone (TSH)
Thyroid-stimulating hormone stimulates the thyroid gland to produce and release thyroid hormones, such as thyroxine (T4) and triiodothyronine (T3).
Thyroid hormones play critical roles in regulating metabolism, growth, and energy balance.

4.Adrenocorticotropic Hormone (ACTH)
Adrenocorticotropic hormone stimulates the adrenal cortex to produce and release cortisol and other glucocorticoid hormones.
Cortisol regulates stress response, metabolism, immune function, and inflammation.

5.Follicle-Stimulating Hormone (FSH)
Follicle-stimulating hormone stimulates the growth and development of ovarian follicles in females and spermatogenesis (sperm production) in males.
In females, FSH also promotes estrogen production and regulates the menstrual cycle.

6.Luteinizing Hormone (LH)
Luteinizing hormone triggers ovulation and stimulates the corpus luteum to produce progesterone in females.
In males, LH stimulates the Leydig cells in the testes to produce testosterone.

Posterior Pituitary (Neurohypophysis):
The posterior pituitary stores and releases hormones produced by the hypothalamus. These hormones are transported along axons from the hypothalamus to the posterior pituitary, where they are released into the bloodstream. The hormones released from the posterior pituitary are:

1.Vasopressin (Antidiuretic Hormone, ADH)
Vasopressin regulates water balance by promoting water reabsorption in the kidneys, reducing urine output, and increasing blood volume and blood pressure.
It also plays a role in vasoconstriction, which helps regulate blood pressure.

2.Oxytocin
Oxytocin is involved in uterine contractions during childbirth and milk ejection (let-down reflex) during breastfeeding.
It also plays roles in social bonding, maternal behavior, sexual arousal, and stress response.

These hormones secreted by the anterior and posterior pituitary glands play vital roles in regulating various physiological functions and maintaining homeostasis in the body.

⏩Answer the following questions (Compulsory) 12

🔸1) What is Leucopoenia and Leucocytosis?

ANSWER:- Leukopenia and leukocytosis are two conditions involving abnormalities in the white blood cell (leukocyte) count in the bloodstream. Here’s an overview of each condition:

Leukopenia:
Leukopenia refers to a decrease in the number of white blood cells (leukocytes) circulating in the bloodstream. A normal white blood cell count typically ranges from 4,000 to 11,000 white blood cells per microliter of blood. Leukopenia is diagnosed when the white blood cell count falls below the lower limit of this normal range. Causes of leukopenia include:

1.Bone Marrow Disorders
Conditions such as aplastic anemia, myelodysplastic syndrome, and leukemia can impair the production of white blood cells in the bone marrow, leading to leukopenia.

2.Chemotherapy or Radiation Therapy
Cancer treatments such as chemotherapy and radiation therapy can suppress bone marrow function, resulting in leukopenia as a side effect.

3.Viral Infections
Some viral infections, such as HIV/AIDS, hepatitis, and influenza, can cause a decrease in white blood cell counts, particularly lymphocytes.

4.Autoimmune Disorders
Autoimmune diseases like systemic lupus erythematosus (SLE) and rheumatoid arthritis can lead to leukopenia due to immune system dysfunction.

5.Medications
Certain medications, such as corticosteroids, antibiotics, and anticonvulsants, can cause leukopenia as an adverse reaction.

Leukocytosis:
Leukocytosis refers to an increase in the number of white blood cells (leukocytes) circulating in the bloodstream. A normal white blood cell count typically ranges from 4,000 to 11,000 white blood cells per microliter of blood. Leukocytosis is diagnosed when the white blood cell count exceeds the upper limit of this normal range. Causes of leukocytosis include:

1.Infections
Bacterial, viral, fungal, or parasitic infections can trigger an immune response, leading to an increase in white blood cell production and release from the bone marrow.

2.Inflammatory Conditions
Inflammatory disorders such as rheumatoid arthritis, inflammatory bowel disease (IBD), and acute pancreatitis can stimulate white blood cell production.

3.Trauma or Tissue Damage
Trauma, surgery, burns, and other forms of tissue damage can cause an inflammatory response, resulting in leukocytosis.

4.Exercise or Stress
Intense physical exertion, emotional stress, or other forms of physiological stress can transiently increase white blood cell counts.

5.Medications
Certain medications, such as corticosteroids, lithium, and epinephrine, can induce leukocytosis as a side effect.

🔸2) Give two difference of Cardiac and Skeletal muscle.

ANSWER:-

Cardiac muscle and skeletal muscle are two types of muscle tissue found in the human body, each with distinct characteristics and functions. Here are two key differences between cardiac and skeletal muscle:

1.Location and Structure
Cardiac Muscle:
Location:
Cardiac muscle is found exclusively in the walls of the heart (myocardium).
Structure: Cardiac muscle cells (cardiomyocytes) are branched, striated (striped), and interconnected by intercalated discs, which contain gap junctions and desmosomes. These interconnections allow for coordinated contraction of the heart muscle.

Skeletal Muscle:
Location: Skeletal muscle is attached to bones and provides the force necessary for movement of the body.
Structure: Skeletal muscle fibers are long, cylindrical, and multinucleated cells. They are arranged in parallel bundles and are characterized by cross-striations (stripes) visible under a microscope due to the organization of contractile proteins.

2.Control and Function
Involuntary vs. Voluntary Control:

Cardiac Muscle: Involuntary:
Cardiac muscle is under involuntary control, meaning it contracts rhythmically without conscious effort. The contraction of the heart is regulated by the autonomic nervous system and specialized cardiac conduction system.

Skeletal Muscle: Voluntary:
Skeletal muscle is under voluntary control, meaning it contracts in response to conscious commands from the brain. Movements such as walking, running, and lifting objects are initiated and controlled by motor neurons in the somatic nervous system

🔸3) Name different papilla on tongue.

ANSWER:-

1.Filiform Papillae
Filiform papillae are the most numerous and smallest of the papillae.
They cover the anterior two-thirds of the tongue’s surface and are responsible for providing friction, aiding in food manipulation and chewing.
Filiform papillae do not contain taste buds.

2.Fungiform Papillae
Fungiform papillae are mushroom-shaped papillae scattered among the filiform papillae, primarily located on the anterior two-thirds of the tongue’s surface.
They contain taste buds on their surface and are involved in taste perception, particularly for sweet and salty tastes.
Fungiform papillae appear as small red dots interspersed among the filiform papillae.

3.Foliate Papillae
Foliate papillae are leaf-like ridges located on the lateral margins of the posterior tongue.
They contain taste buds and are involved in taste perception, particularly for sour tastes.
Foliate papillae are less prominent in adult humans compared to other mammals.

4.Circumvallate Papillae
Circumvallate papillae, also known as vallate papillae, are large, dome-shaped papillae located in a V-shaped row at the back of the tongue.
They are surrounded by a circular groove and contain numerous taste buds on their surface.
Circumvallate papillae are primarily involved in taste perception, particularly for bitter tastes.
These papillae are innervated by the glossopharyngeal nerve (cranial nerve IX).

Additionally, there are also some minor types of papillae, such as:

5. Follicular Papillae:

• Follicular papillae are small, round elevations scattered on the posterior dorsal surface of the tongue.
• They contain numerous lymphoid follicles and play a role in the immune response of the oral cavity.

🔸4) Name two type of Immunity.

ANSWER:- 1.Innate Immunity
Innate immunity, also known as natural or nonspecific immunity, provides immediate defense against pathogens and other foreign substances.
It is the body’s first line of defense and includes physical barriers (such as the skin and mucous membranes), chemical barriers (such as stomach acid and antimicrobial peptides), and cellular components (such as macrophages, neutrophils, and natural killer cells).

• Innate immunity is not specific to particular pathogens and does not confer long-lasting immunity upon exposure to a specific pathogen.

2.Adaptive Immunity
Adaptive immunity, also known as acquired or specific immunity, is a highly specific and tailored immune response that develops after exposure to a specific pathogen.
It involves the recognition and memory of specific antigens (molecules on the surface of pathogens) by specialized immune cells called lymphocytes, particularly T cells and B cells.
Adaptive immunity provides long-lasting protection against specific pathogens by generating immunological memory. Upon subsequent encounters with the same pathogen, the immune system mounts a more rapid and effective response.
Adaptive immunity is characterized by the production of antibodies (humoral immunity) by B cells and the activation of cytotoxic T cells (cell-mediated immunity), which work together to eliminate pathogens and infected cells.

Both innate and adaptive immunity play essential roles in defending the body against infectious agents and maintaining overall health and wellbeing.

🔸5) Define Homeostasis. Name type of Feedback.

ANSWER:- Homeostasis is the physiological process by which living organisms maintain a stable internal environment despite external changes. It involves the regulation of various factors such as body temperature, pH, blood glucose levels, and fluid balance within narrow ranges to ensure optimal cellular function and overall health.

1.Negative Feedback
Negative feedback is the most common type of feedback mechanism in homeostasis.
In negative feedback, the response to a stimulus acts to counteract or reverse the initial change, bringing the system back to its set point or desired level.
Examples of negative feedback include the regulation of body temperature, blood pressure, blood glucose levels, and hormone secretion.
Negative feedback loops typically involve three components: a sensor (receptor) that detects changes in the internal environment, a control center (integrator) that compares the detected changes to a set point, and an effector that produces a response to counteract the changes and restore homeostasis.

2.Positive Feedback
Positive feedback amplifies or reinforces the initial change or deviation from the set point, rather than restoring the system to its original state.
While less common in homeostasis, positive feedback plays a role in certain physiological processes such as childbirth, blood clotting, and the immune response.
In positive feedback loops, the initial stimulus triggers a response that leads to an increase in the stimulus, which in turn amplifies the response further.
Positive feedback loops are typically self-perpetuating and may continue until an external intervention interrupts the process.

🔸6) Name two methods of artificial respiration.

ANSWER:-1.Mechanical Ventilation
Mechanical ventilation, also known as assisted ventilation or artificial ventilation, involves the use of a mechanical ventilator to assist or replace spontaneous breathing in individuals who are unable to breathe adequately on their own.
A mechanical ventilator delivers a controlled volume of air or oxygen-enriched gas mixture into the lungs through an endotracheal tube or tracheostomy tube.
The ventilator can be set to provide breaths at a predetermined rate and tidal volume, and may also deliver positive end-expiratory pressure (PEEP) to maintain lung inflation and improve oxygenation.
Mechanical ventilation is commonly used in intensive care units (ICUs) for patients with respiratory failure, acute lung injury, or conditions that compromise respiratory function.

2.Manual Resuscitation (Bag-Valve-Mask Ventilation)
Manual resuscitation, also known as bag-valve-mask (BVM) ventilation or manual ventilation, involves the use of a self-inflating bag connected to a face mask to manually deliver breaths to a patient.
During manual resuscitation, the rescuer places a face mask securely over the patient’s nose and mouth and uses the self-inflating bag to deliver positive pressure breaths.
The rescuer squeezes the bag to deliver a tidal volume of air or oxygen-enriched gas mixture into the patient’s lungs, and then releases the bag to allow passive exhalation.