ANATOMY VS.

PHYSIOLOGY

Anatomy is the study of the structure of body parts, including their form
and organization.

Physiology is the study of the function of body parts, explaining how they
work and interact.

Example: The trachea's rigid cartilage rings (anatomy) maintain airway

patency to allow breathing (physiology).

CELL TRANSPORT PROCESSES

Diffusion is the movement of substances from an area of high

concentration to low concentration.

Osmosis is the diffusion of water through a selectively permeable

membrane.

Facilitated diffusion uses protein channels to allow larger molecules to

pass through membranes.

Active transport uses ATP to move substances against their concentration

gradients.

CELL ORGANELLES AND THEIR FUNCTIONS

Nucleus: Contains DNA and regulates cell activities.

Nucleolus: Produces ribosomes by synthesizing rRNA.

Ribosomes: Sites of protein synthesis; found freely in cytoplasm or on

rough ER.
Rough endoplasmic reticulum: Studded with ribosomes; helps in protein
modification and transport.

Smooth endoplasmic reticulum: Lacks ribosomes; synthesizes lipids and

detoxifies substances.

Golgi apparatus: Modifies, packages, and distributes proteins and lipids.

Mitochondria: Site of ATP production; the powerhouse of the cell.

Lysosomes: Contain digestive enzymes that break down waste and

damaged organelles.

Peroxisomes: Break down fatty acids and detoxify harmful substances.

Centrioles: Involved in organizing spindle fibers during cell division.

Cytoskeleton: Provides structural support and shape to the cell.

Plasma membrane: Regulates movement of substances in and out of the

cell.

Cytoplasm: Jelly-like substance where cell organelles are suspended.

Vesicles: Membranous sacs used for transport and storage.

Flagella: Long, whip-like tail that propels cells (e.g., sperm cells).

Cilia: Short, hair-like projections that move substances across the surface.

Microvilli: Microscopic projections that increase surface area for

absorption.
BODY STRUCTURE AND ORGANIZATION

Levels of Structural Organization:

Chemical level: Includes atoms and molecules.

Cellular level: Basic structural and functional units of life.

Tissue level: Groups of similar cells performing specific functions.

Organ level: Structures composed of two or more types of tissues.

Organ system level: Organs working together to perform complex

functions.

Organism level: The complete living being.

Major Body Cavities:

Cranial cavity: Contains the brain.

Spinal cavity: Contains the spinal cord.

Thoracic cavity: Contains lungs, heart, esophagus, and trachea.

Abdominal cavity: Contains digestive organs like stomach, intestines, liver,

and kidneys.

Pelvic cavity: Contains urinary bladder and reproductive organs.

Abdominopelvic cavity: Combined abdominal and pelvic cavities.

Body Planes:

Sagittal plane: Divides the body into left and right parts.

Midsagittal plane: Divides the body into equal left and right halves.

Frontal (coronal) plane: Divides the body into front and back portions.

Transverse plane: Divides the body into upper and lower parts.

Body Regions and Quadrants:

Right upper quadrant: Contains liver, gallbladder, and right kidney.

Left upper quadrant: Contains stomach, spleen, and pancreas.

Right lower quadrant: Contains appendix and right ovary.

Left lower quadrant: Contains left ovary and sigmoid colon.

Organ Systems and Their Functions:

Integumentary system: Provides protection and regulates temperature.

Skeletal system: Provides structure, support, and produces blood cells.

Muscular system: Allows movement and produces body heat.

Nervous system: Coordinates body activities through electrical signals.

Endocrine system: Regulates body functions using hormones.

Cardiovascular system: Transports blood, oxygen, and nutrients.

Lymphatic and immune system: Defends the body against pathogens.

Respiratory system: Facilitates gas exchange between air and blood.

Digestive system: Breaks down food and absorbs nutrients.

Urinary system: Removes waste and maintains fluid balance.

Reproductive system: Produces offspring.

TISSUES

The four primary tissue types are epithelial, connective, muscle, and
nervous tissue.

Epithelial tissue covers body surfaces and lines cavities.

Connective tissue supports and binds other tissues.

Muscle tissue allows movement.

Nervous tissue conducts electrical impulses for communication.

EPITHELIAL TISSUES

Simple squamous epithelium: Found in alveoli; thin for diffusion.

Stratified squamous epithelium: Found in the esophagus and skin;

protective.
Simple cuboidal epithelium: Found in kidney tubules; absorption and
secretion.

Simple columnar epithelium: Found in the digestive tract; absorption.

Pseudostratified ciliated columnar epithelium: Found in the trachea;

moves mucus.

CONNECTIVE TISSUES

Dense regular connective tissue: Found in tendons and ligaments; strong

and rope-like.

Areolar tissue: Loose connective tissue beneath the skin.

Adipose tissue: Stores fat; insulates and cushions.

Fibrocartilage: Found in intervertebral discs and knee meniscus; strong

and shock-absorbing.

Hyaline cartilage: Found in the nose, trachea, and joints.

Bone: Supports and protects; produces blood cells.

Blood: Transports oxygen, nutrients, and waste.

BODY ORIENTATION AND TERMINOLOGY

Anatomical position: Standing upright, facing forward, arms at sides,
palms facing forward.

Directional terms:

Superior: Toward the head.

Inferior: Toward the feet.

Anterior: Toward the front.

Posterior: Toward the back.

Lateral: Away from the midline.

Medial: Toward the midline.

Proximal: Closer to the point of origin.

Distal: Further from the point of origin.

INTEGUMENTARY SYSTEM

Epidermis: Outermost layer; affected by superficial burns.

Dermis: Middle layer; contains blood vessels, nerves, and glands.

Hypodermis: Deepest layer; contains fat and connective tissue.

Stratum corneum: Outer layer of dead, keratin-filled cells.

Skin glands:
Eccrine glands: Secrete sweat for thermoregulation.

Apocrine glands: Found in armpits; produce odor after puberty.

Sebaceous glands: Secrete sebum; overactive in acne.

Burn types:

First-degree burn: Red, painful; affects epidermis only.

Second-degree burn: Blisters; affects epidermis and part of dermis.

Third-degree burn: Destroys all skin layers; may be painless due to nerve
damage.

Melanocytes: Produce melanin; affected in depigmentation.

Langerhans cells: Trigger immune response to irritants like insect bites.

Arrector pili muscle: Causes hair to stand up; creates goosebumps.

SKELETAL SYSTEM

Osteoblasts: Build new bone matrix.

Osteoclasts: Break down bone matrix; increased activity in osteoporosis.

Osteocytes: Mature bone cells.

Parathyroid hormone stimulates osteoclasts indirectly via osteoblasts.

Bone types:

Long bones: Femur, humerus.

Short bones: Carpals, tarsals.

Flat bones: Skull, ribs.

Irregular bones: Vertebrae.

Sesamoid bones: Patella.

Bone healing process:

Hematoma formation

Soft callus formation

Hard callus formation

Bone remodeling

Joints:

Shoulder: Ball-and-socket joint.

Temporomandibular joint: Synovial joint.

Sutures in newborn skull: Immovable joints.

Epiphyseal plate: Growth plate; site of bone lengthening in children.

Rickets: Bone disorder due to vitamin D deficiency; causes bowed legs.

Red bone marrow: Site of red blood cell production.

MUSCULAR SYSTEM

Muscle types:

Skeletal muscle: Voluntary, striated, attached to bones.

Cardiac muscle: Involuntary, striated, found only in the heart.

Smooth muscle: Involuntary, non-striated, found in walls of hollow organs.

Muscle contractions:

Isometric: Muscle length does not change; tension increases.

Concentric: Muscle shortens during contraction.

Eccentric: Muscle lengthens while maintaining tension.

Muscle physiology:

Hypertrophy: Increase in muscle fiber size due to training.

Atrophy: Decrease in muscle fiber size due to disuse.

Neuromuscular junction: Site where nerve signal stimulates muscle;

blocked acetylcholine receptors result in paralysis.

Key muscle structures:

Sarcomere: Functional unit of muscle contraction.

Sarcoplasmic reticulum: Stores calcium ions needed for contraction.

Calcium: Triggers contraction.

ATP: Provides energy for contraction.

Endomysium: Connective tissue surrounding individual muscle fibers.

Rectus femoris: One of the quadriceps muscles.