BIO 141: Study Guide for Anatomy & Physiology – Modules 1, 4, 5, and 23

Introduction to Anatomy and Physiology

Definitions and Scope

Anatomy and physiology are foundational sciences in understanding the human body. Anatomy is the study of the structure of body parts, while physiology focuses on their function.

• Anatomy: Examines the form and organization of body structures.

• Physiology: Explores how those structures work and interact.

Gross anatomy studies structures visible to the naked eye, while microscopic anatomy (including histology and cytology) examines structures at the cellular and tissue levels.

Characteristics of Living Things

• Organization

• Metabolism

• Growth and development

• Responsiveness to stimuli

• Regulation (homeostasis)

• Reproduction

Levels of Organization

The human body is organized into six hierarchical levels:

• Chemical (atoms, molecules)

• Cellular (cells)

• Tissue (groups of similar cells)

• Organ (two or more tissue types)

• Organ system (organs working together)

• Organism (the complete individual)

Body Systems and Functions

The human body has eleven organ systems, each with primary functions:

• Integumentary: Protection, temperature regulation

• Skeletal: Support, movement, protection

• Muscular: Movement, heat production

• Nervous: Control, communication

• Endocrine: Hormone production, regulation

• Cardiovascular: Transport of nutrients and gases

• Lymphatic: Immunity, fluid balance

• Respiratory: Gas exchange

• Digestive: Nutrient breakdown and absorption

• Urinary: Waste elimination, water balance

• Reproductive: Production of offspring

Anatomical Position and Terminology

• Anatomical position: Standing upright, facing forward, arms at sides, palms forward, feet flat and forward.

• Directional terms: Superior/inferior, anterior/posterior, medial/lateral, proximal/distal, superficial/deep.

• Body regions: E.g., cephalic (head), thoracic (chest), abdominal, pelvic, etc.

Body Planes and Cavities

• Planes: Sagittal (left/right), frontal (anterior/posterior), transverse (superior/inferior).

• Body cavities: Dorsal (cranial, vertebral), ventral (thoracic, abdominopelvic).

• Abdominopelvic quadrants: RUQ, LUQ, RLQ, LLQ.

• Abdominopelvic regions: Nine regions (e.g., epigastric, umbilical, hypogastric, etc.).

Serous Membranes

• Layers: Parietal (lines cavity), visceral (covers organ), serous fluid in between.

• Main serous membranes: Pleura (lungs), pericardium (heart), peritoneum (abdominal organs).

Homeostasis and Feedback

• Homeostasis: Maintenance of a stable internal environment.

• Feedback loop components: Receptor, control center, effector, stimulus, response.

• Negative feedback: Opposes change (e.g., body temperature regulation).

• Positive feedback: Amplifies change (e.g., blood clotting).

Gradients and Cell Communication

• Gradient: Difference in concentration, pressure, or electrical charge (e.g., concentration gradient).

• Cell communication: Chemical signaling, electrical signaling.

Histology

Definition and Tissue Types

Histology is the study of tissues. A tissue is a group of similar cells performing a common function.

• Four main tissue types: Epithelial, connective, muscle, nervous.

Extracellular Matrix (ECM)

• Components: Ground substance (water, glycosaminoglycans, proteoglycans, glycoproteins), fibers (collagen, elastic, reticular).

Membrane Junctions

• Tight junctions: Prevent leakage (e.g., intestinal lining).

• Desmosomes: Provide strength (e.g., skin).

• Gap junctions: Allow communication (e.g., cardiac muscle).

Epithelial Tissue

• Characteristics: Cellularity, polarity, avascularity, regeneration.

• Functions: Protection, absorption, filtration, secretion, sensation.

• Classification by layers: Simple (one layer), stratified (multiple layers).

• Classification by shape: Squamous (flat), cuboidal (cube-shaped), columnar (tall).

• Examples: Simple squamous (alveoli), stratified squamous (skin), simple cuboidal (kidney tubules), simple columnar (intestine).

• Ciliated vs. nonciliated: Ciliated (trachea), nonciliated (intestine).

• Keratinized vs. nonkeratinized: Keratinized (skin), nonkeratinized (esophagus).

Glands and Secretions

• Exocrine glands: Secrete via ducts (e.g., sweat, salivary glands).

• Endocrine glands: Secrete hormones into blood.

• Goblet cells: Unicellular glands producing mucus.

• Modes of secretion: Merocrine (exocytosis), apocrine (part of cell), holocrine (whole cell).

Connective Tissue

• Basic components: Cells, fibers, ground substance.

• Functions: Support, protection, transport, storage.

• Cell types: Fibroblasts, adipocytes, macrophages, mast cells.

• Types: Areolar, dense regular, dense irregular, elastic, reticular, adipose, cartilage (hyaline, elastic, fibrocartilage), bone, blood.

Muscle and Nervous Tissue

• Muscle types: Skeletal (voluntary, striated), cardiac (involuntary, striated, intercalated discs), smooth (involuntary, non-striated).

• Locations: Skeletal (attached to bones), cardiac (heart), smooth (walls of organs).

• Nervous tissue: Neurons (transmit signals), neuroglia (support neurons).

Body Membranes and Tissue Repair

• Membranes: Mucous, serous, cutaneous, synovial.

• Tissue repair: Regeneration (restores function), fibrosis (scar tissue formation).

Integumentary System

Skin Structure and Function

• Layers: Epidermis (outer), dermis (middle), hypodermis (below dermis).

• Functions: Protection, sensation, thermoregulation, excretion, vitamin D synthesis.

Cell Types and Layers

• Keratinocytes: Main cell, produce keratin.

• Melanocytes: Produce melanin (pigment).

• Merkel cells: Sensory receptors.

• Langerhans cells: Immune defense.

• Five layers of epidermis: Stratum basale, spinosum, granulosum, lucidum (thick skin only), corneum.

Thick vs. Thin Skin

• Thick skin: Palms, soles; has all five layers, no hair.

• Thin skin: Covers most of body; fewer layers, has hair.

Dermis and Hypodermis

• Dermis: Papillary (upper, loose connective), reticular (lower, dense irregular connective).

• Hypodermis: Adipose and areolar tissue; insulates and anchors skin.

Skin Color and Pigments

• Pigments: Melanin, carotene, hemoglobin.

• Melanin: Produced by melanocytes, protects against UV.

• Erythema: Redness due to increased blood flow.

Hair, Nails, and Glands

• Hair: Protection, sensation, thermoregulation; types: lanugo, vellus, terminal.

• Nails: Protect digits, aid in manipulation.

• Glands: Sweat (merocrine, apocrine), sebaceous (oil).

Burns and Skin Cancer

• Burns: First-degree (epidermis), second-degree (dermis), third-degree (full thickness).

• Rule of nines: Estimates burn area as multiples of 9% of body surface.

• Skin cancers: Basal cell carcinoma, squamous cell carcinoma, malignant melanoma.

Cell Growth Terms

• Hypertrophy: Increase in cell size.

• Hyperplasia: Increase in cell number.

• Atrophy: Decrease in cell size or number.

• Dysplasia: Abnormal cell growth.

• Neoplasia: Uncontrolled cell growth (tumor).

Metabolism and Nutrition

Metabolic Processes

• Metabolism: All chemical reactions in the body.

• Anabolism: Building complex molecules from simpler ones.

• Catabolism: Breaking down molecules to release energy.

ATP and Energy Coupling

• ATP: Main energy currency of the cell.

• Exergonic reactions: Release energy (e.g., ATP hydrolysis).

• Endergonic reactions: Require energy input.

• Coupling: Exergonic reactions drive endergonic processes.

• ATP hydrolysis equation:

$\mathrm{ATP} + \mathrm{H}_2\mathrm{O} \rightarrow \mathrm{ADP} + \mathrm{P_i} + \text{energy}$

Redox Reactions and Electron Carriers

• Oxidation: Loss of electrons.

• Reduction: Gain of electrons.

• Electron carriers: NAD+, FAD (in cytosol and mitochondria).

• Electromotive force: The force that drives electron flow.

ATP Generation Pathways

• Substrate-level phosphorylation: Direct transfer of phosphate to ADP.

• Oxidative phosphorylation: Uses electron transport chain and chemiosmosis.

Glucose Catabolism

• Glycolysis: Occurs in cytosol; glucose → 2 pyruvate, 2 ATP, 2 NADH.

• Intermediate step: Pyruvate → Acetyl-CoA (aerobic); pyruvate → lactate (anaerobic).

• Citric Acid Cycle: In mitochondria; Acetyl-CoA → CO2, 2 ATP, 6 NADH, 2 FADH2.

• Electron Transport Chain: Produces most ATP via oxidative phosphorylation.

• Role of oxygen: Final electron acceptor in ETC.

• Overall aerobic glucose catabolism equation:

$\mathrm{C}_6\mathrm{H}_{12}\mathrm{O}_6 + 6\mathrm{O}_2 \rightarrow 6\mathrm{CO}_2 + 6\mathrm{H}_2\mathrm{O} + 36-38\ \mathrm{ATP}$

• ATP yield: 36-38 ATP per glucose (aerobic).

Nutrient Monomers

• Carbohydrates: Glucose

• Lipids: Fatty acids

• Proteins: Amino acids

Table: Comparison of Epithelial Tissue Types (Example)

Type	Layers	Cell Shape	Location	Function
Simple Squamous	1	Flat	Alveoli, blood vessels	Diffusion, filtration
Stratified Squamous	Multiple	Flat	Skin, mouth, esophagus	Protection
Simple Cuboidal	1	Cube-shaped	Kidney tubules	Secretion, absorption
Simple Columnar	1	Tall	Small intestine	Absorption, secretion

Additional info: These notes are based on the learning objectives for BIO 141 and include expanded academic context for clarity and completeness.