BIOL 237: Introduction to Anatomy & Physiology – Exam 1 Study Guide

An Introduction to Anatomy & Physiology

Overview of Body Systems

The human body is organized into several major systems, each with specific functions and components. Understanding these systems is fundamental to the study of anatomy and physiology.

• Integumentary System: Protects the body, regulates temperature, and provides sensory information. Includes skin, hair, nails, and glands.

• Skeletal System: Provides support, protection, and movement. Composed of bones, cartilage, and joints.

• Muscular System: Produces movement, maintains posture, and generates heat. Includes skeletal muscles and tendons.

• Nervous System: Directs immediate responses to stimuli, coordinates activities of other systems. Includes brain, spinal cord, and nerves.

• Cardiovascular System: Distributes blood, nutrients, gases, and waste. Includes heart and blood vessels.

• Lymphatic System: Defends against infection and disease. Includes lymph nodes, lymphatic vessels, spleen, and thymus.

• Respiratory System: Delivers air to sites of gas exchange. Includes lungs, trachea, and bronchi.

• Digestive System: Processes food, absorbs nutrients, and eliminates waste. Includes stomach, intestines, liver, and pancreas.

• Urinary System: Eliminates waste, regulates water and electrolytes. Includes kidneys, ureters, bladder, and urethra.

• Reproductive System: Produces sex cells and hormones. Includes testes, ovaries, uterus, and associated structures.

Relationship Between Form and Function

In anatomy and physiology, form (structure) and function (what it does) are closely related. The structure of a body part determines its function, and vice versa.

• Example: The thin, flat shape of red blood cells increases surface area for gas exchange.

Smallest Unit of Life

• The cell is the smallest unit of life capable of performing all vital physiological functions.

• Cells are the building blocks of all living organisms.

Blood Cells and Their Functions

• Red Blood Cells (Erythrocytes): Transport oxygen and carbon dioxide.

• White Blood Cells (Leukocytes): Defend against infection and disease.

• Platelets (Thrombocytes): Involved in blood clotting.

Anatomical Terminology

• Directional Terms: Describe the location of structures (e.g., anterior/posterior, superior/inferior, medial/lateral).

• Anatomical Position: Body standing upright, facing forward, arms at sides, palms facing forward.

• Planes of the Body:

  • Frontal (Coronal) Plane: Divides body into anterior and posterior parts.

  • Sagittal Plane: Divides body into right and left parts.

  • Transverse (Horizontal) Plane: Divides body into superior and inferior parts.

Homeostasis and Feedback Mechanisms

Homeostasis

Homeostasis is the maintenance of a stable internal environment despite external changes. It is essential for normal body function and survival.

• Maintained by feedback systems involving receptors, control centers, and effectors.

Parts of a Reflex

• Receptor: Detects stimulus.

• Control Center: Processes information and determines response.

• Effector: Carries out the response.

Negative vs. Positive Feedback

• Negative Feedback: Reverses a change to maintain homeostasis (e.g., regulation of body temperature, blood glucose levels).

• Positive Feedback: Enhances or amplifies a change (e.g., blood clotting, childbirth contractions).

Body Cavities and Serous Membranes

Body Cavities

• Cranial Cavity: Contains the brain.

• Thoracic Cavity: Contains heart and lungs.

• Abdominal Cavity: Contains digestive organs.

• Pelvic Cavity: Contains urinary and reproductive organs.

Serous Membranes

• Pleura: Surrounds the lungs.

• Pericardium: Surrounds the heart.

• Peritoneum: Lines the abdominal cavity and covers abdominal organs.

Cellular Level of Organization

Cell Organelles

• Nucleus: Contains genetic material (DNA).

• Mitochondria: Site of ATP (energy) production.

• Endoplasmic Reticulum (ER): Synthesizes proteins (rough ER) and lipids (smooth ER).

• Golgi Apparatus: Modifies, sorts, and packages proteins.

• Lysosomes: Contain digestive enzymes.

• Plasma Membrane: Regulates entry and exit of substances.

Tonicity and Its Effects on Cells

• Tonicity refers to the ability of a solution to cause a cell to gain or lose water.

• Isotonic: No net water movement; cell remains the same size.

• Hypotonic: Water enters the cell; cell may swell and burst.

• Hypertonic: Water leaves the cell; cell shrinks.

Phagocytosis

• Phagocytosis is a form of endocytosis where a cell engulfs large particles or pathogens.

• Performed by specialized cells such as macrophages.

Tissue Level of Organization

Definition and Types of Tissues

• Tissue: A group of similar cells that perform a specific function.

• Four basic types:

  • Epithelial Tissue: Covers surfaces, lines cavities, forms glands.

  • Connective Tissue: Supports, protects, binds other tissues.

  • Muscle Tissue: Produces movement.

  • Nervous Tissue: Transmits electrical impulses.

Examples of Tissue Cells

• Chondrocytes: Cartilage cells.

• Osteocytes: Bone cells.

• Fibroblasts: Produce fibers in connective tissue.

• Macrophages: Engulf pathogens and debris.

The Integumentary System

Components and Functions

• Consists of skin, hair, nails, sweat glands, and sebaceous glands.

• Functions: Protection, temperature regulation, sensation, vitamin D synthesis.

Factors Affecting Skin Color

• Pigments: Melanin, carotene, hemoglobin.

• Vasodilation/Vasoconstriction: Changes in blood flow affect skin color.

Blood Supply to the Epidermis

• The epidermis is avascular; it receives nutrients via diffusion from blood vessels in the dermis.

Fingerprints and Their Structure

• Formed by dermal papillae in the dermis, which create ridges on the epidermis.

• Unique to each individual.

Layers of the Epidermis

• From deep to superficial:

  1. Stratum basale

  2. Stratum spinosum

  3. Stratum granulosum

  4. Stratum lucidum (only in thick skin)

  5. Stratum corneum

Types of Burns

• First-degree: Affects only the epidermis (redness, pain).

• Second-degree: Affects epidermis and part of dermis (blisters).

• Third-degree: Destroys epidermis and dermis (may extend to subcutaneous tissue).

Arrector Pili Muscle

• Small muscle attached to hair follicles.

• Contracts to cause "goosebumps" and elevate hair.

Sweat Glands

• Eccrine (Merocrine) Glands: Widely distributed, secrete watery sweat for thermoregulation.

• Apocrine Glands: Found in armpits and groin, secrete thicker sweat, become active at puberty.

Keratin

• Keratin: A tough, fibrous protein found in skin, hair, and nails.

• Provides protection and waterproofing.

Skin Cancer

• Caused by uncontrolled growth of skin cells, often due to UV exposure.

• Main types: Basal cell carcinoma, squamous cell carcinoma, melanoma.

Summary Table: Major Tissue Types and Functions

Tissue Type	Main Function	Example Location
Epithelial	Protection, absorption, secretion	Skin, lining of GI tract
Connective	Support, binding, protection	Bone, cartilage, blood
Muscle	Movement	Skeletal muscles, heart
Nervous	Transmit impulses	Brain, spinal cord, nerves

Key Equations and Concepts

• Osmosis: Movement of water across a semipermeable membrane from low to high solute concentration.

• Homeostatic Regulation: $Stimulus \rightarrow Receptor \rightarrow Control\ Center \rightarrow Effector \rightarrow Response$

Additional info: Some explanations and examples have been expanded for clarity and completeness based on standard introductory anatomy and physiology curricula.