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

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 foundational to anatomy and physiology.

• Nervous System: Controls and coordinates body activities by transmitting electrical signals.

• Muscular System: Produces movement, maintains posture, and generates heat.

• Skeletal System: Provides support, protection, and stores minerals; site of blood cell formation.

• Cardiovascular System: Transports nutrients, gases, hormones, and wastes through blood.

• Respiratory System: Facilitates gas exchange (oxygen and carbon dioxide) with the environment.

• Digestive System: Breaks down food, absorbs nutrients, and eliminates waste.

• Urinary System: Removes waste from blood and regulates water, electrolyte, and acid-base balance.

• Integumentary System: Protects the body, regulates temperature, and provides sensory information.

• Endocrine System: Produces hormones that regulate body processes.

• Lymphatic/Immune System: Defends against infection and disease, returns tissue fluids to bloodstream.

• Reproductive System: Produces gametes and hormones for reproduction.

Example: The digestive system includes organs such as the stomach, intestines, and liver, which work together to process food and absorb nutrients.

Form and Function Relationship

In anatomy and physiology, form (structure) and function (what it does) are closely related. The shape and structure of a body part often determine its function.

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

Levels of Organization

The body is organized from the simplest to the most complex levels:

• Chemical Level: Atoms and molecules

• Cellular Level: Cells are the smallest unit of life

• Tissue Level: Groups of similar cells performing a common function

• Organ Level: Two or more tissue types working together

• Organ System Level: Groups of organs with a common function

• Organismal Level: The whole living being

Cells and Organelles

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.

Cell Organelles

• Nucleus: Contains genetic material (DNA); controls cell activities.

• Mitochondria: Site of ATP (energy) production.

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

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

• Lysosomes: Contain digestive enzymes to break down waste.

• 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 size remains the same.

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

• Hypertonic: Water leaves the cell; cell shrinks.

Phagocytosis

Phagocytosis is a type of endocytosis where a cell engulfs large particles or microorganisms.

• Performed by specialized cells such as macrophages.

• Important for defense against pathogens.

Anatomical Terminology

Directional Terms

• Superior (Cranial): Toward the head

• Inferior (Caudal): Toward the feet

• Anterior (Ventral): Toward the front

• Posterior (Dorsal): Toward the back

• Medial: Toward the midline

• Lateral: Away from the midline

• Proximal: Closer to the point of attachment

• Distal: Farther from the point of attachment

• Superficial: Toward the surface

• Deep: Away from the surface

Anatomical Position

The standard reference position for the body:

• Standing upright

• Facing forward

• Arms at sides, palms facing forward

• Feet slightly apart

Body Planes

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

• Sagittal Plane: Divides body into right and left parts. Midsagittal is exactly at midline; parasagittal is off-center.

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

Body Cavities

• Dorsal Cavity: Contains cranial and vertebral cavities (brain and spinal cord).

• Ventral Cavity: Contains thoracic and abdominopelvic cavities.

• Thoracic Cavity: Contains heart and lungs.

• Abdominal Cavity: Contains digestive organs.

• Pelvic Cavity: Contains urinary bladder, reproductive organs.

Serous Membranes

• Pleura: Surrounds the lungs.

• Pericardium: Surrounds the heart.

• Peritoneum: Surrounds abdominal organs.

• Each has a parietal (lines cavity) and visceral (covers organ) layer.

Homeostasis and Feedback Mechanisms

Homeostasis

Homeostasis is the maintenance of a stable internal environment despite external changes.

• Involves receptors (detect changes), control center (processes information), and effectors (respond to changes).

Feedback Mechanisms

• Negative Feedback: Reverses a change to maintain balance. Example: Regulation of body temperature.

• Positive Feedback: Enhances or amplifies a change. Example: Blood clotting, labor contractions.

Tissues and Their Types

Definition of Tissues

A tissue is a group of similar cells that perform a specific function.

Types of Tissues

• Epithelial Tissue: Covers surfaces, lines cavities, forms glands. Function: Protection, absorption, secretion.

• Connective Tissue: Supports, binds, and protects organs. Examples: Bone, cartilage, blood, adipose tissue.

• Muscle Tissue: Produces movement. Types: Skeletal, cardiac, smooth.

• Nervous Tissue: Transmits electrical impulses for communication.

Common Tissue Cells

• Chondrocytes: Cartilage cells.

• Osteocytes: Bone cells.

• Fibroblasts: Produce fibers in connective tissue.

• Macrophages: Engulf pathogens and debris.

The Integumentary System

Components

• Skin (epidermis and dermis)

• Hair

• Nails

• Glands (sweat and sebaceous)

Skin Color

• Pigments: Melanin (brown/black), carotene (yellow/orange), hemoglobin (red).

• Vasodilation: Increases blood flow, causing redness.

• Vasoconstriction: Decreases blood flow, causing paleness.

Blood Supply to the Epidermis

• The epidermis is avascular (no direct blood supply); nutrients diffuse from blood vessels in the dermis.

Fingerprints and Their Structure

• Formed by dermal papillae (projections of the dermis into the epidermis).

• Unique to each individual; improve grip.

Layers of the Epidermis

• Stratum Corneum (outermost)

• Stratum Lucidum (only in thick skin)

• Stratum Granulosum

• Stratum Spinosum

• Stratum Basale (deepest)

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 affect deeper tissues; numbness due to nerve damage.

Arrector Pili Muscle

• Small muscle attached to hair follicles.

• Contracts to cause "goosebumps" in response to cold or fear.

Sweat Glands

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

• Apocrine Glands: Found in armpits, groin; secrete thicker sweat, often associated with body odor.

Keratin

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

• Provides protection and waterproofing.

Skin Cancer

• Caused by uncontrolled cell growth, often due to UV radiation.

• 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	Communication, control	Brain, spinal cord, nerves

Key Definitions and Concepts

• Homeostasis: Maintenance of stable internal conditions.

• Phagocytosis: Cell engulfs large particles.

• Tonicity: Effect of solution on cell volume.

• Keratin: Protective protein in skin, hair, nails.

• Chondrocyte: Cartilage cell.

• Osteocyte: Bone cell.

• Fibroblast: Connective tissue cell that produces fibers.

• Macrophage: Immune cell that engulfs pathogens.

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