Anatomy & Physiology Study Guide: Key Concepts and Structures

Chapter 1: Introduction to Anatomy & Physiology

Anatomical Position and Directional Terms

The anatomical position is a standardized posture used to describe locations and directions on the human body. Directional terms help specify the relative positions of body parts.

• Proximal/Distal: Proximal means closer to the point of attachment; distal means farther away.

• Anterior/Posterior: Anterior refers to the front; posterior to the back.

• Body Planes: Sagittal (divides left/right), frontal (divides front/back), transverse (divides top/bottom).

Body Cavities and Organ Systems

The body contains several cavities that house organs and organ systems, each with specific functions.

• Major Cavities: Cranial, thoracic, abdominal, pelvic.

• Organ Systems: Examples include digestive, respiratory, circulatory, and nervous systems.

Homeostasis

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

• Negative Feedback: Mechanism that reverses a change to maintain balance (e.g., temperature regulation).

• Positive Feedback: Mechanism that amplifies a change (e.g., blood clotting).

Example:

Regulation of blood glucose levels by insulin and glucagon.

Chapter 2: Basic Chemistry for Anatomy & Physiology

Atomic Structure and Chemical Bonds

Atoms are the basic units of matter, composed of protons, neutrons, and electrons. Chemical bonds form molecules essential for life.

• Atomic Number: Number of protons in an atom.

• Mass Number: Sum of protons and neutrons.

• Isotopes: Atoms of the same element with different numbers of neutrons.

Molecular Formulas and Chemical Properties

• Simple Molecular Formulas: Examples include H2O, CO2.

• Acids and Bases: Acids release H+; bases accept H+. pH scale measures acidity/basicity.

• Enzyme Function: Enzymes are biological catalysts that speed up chemical reactions.

Major Elements and Molecules in the Body

• Major Elements: Carbon (C), Hydrogen (H), Oxygen (O), Nitrogen (N).

• Biomolecules: Carbohydrates, lipids, proteins, nucleic acids.

ATP Structure and Cellular Work

ATP (adenosine triphosphate) is the primary energy carrier in cells.

• ATP Structure: Adenine base, ribose sugar, three phosphate groups.

• Cellular Work: ATP powers muscle contraction, active transport, and biosynthesis.

Formula:

$\text{ATP} \rightarrow \text{ADP} + \text{P}_i + \text{Energy}$

Chapter 3: Cell Structure and Function

Organelles and Their Functions

Cells contain specialized structures called organelles, each with distinct roles.

• Ribosomes: Protein synthesis.

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

• Mitochondria: ATP production.

RNA Types and Protein Synthesis

• mRNA: Messenger RNA carries genetic code from DNA to ribosomes.

• tRNA: Transfer RNA brings amino acids to ribosomes.

• rRNA: Ribosomal RNA forms part of ribosome structure.

Transcription and Translation

Transcription is the process of copying DNA into RNA; translation is the synthesis of proteins from RNA.

• Transcription: DNA template is used to make mRNA.

• Translation: mRNA sequence is decoded to build a protein.

Mitosis and Cellular Transport

• Mitosis: Cell division resulting in two identical daughter cells.

• Cellular Transport: Passive (osmosis, diffusion) and active (endocytosis, exocytosis) mechanisms.

Example:

Osmosis is the movement of water across a semipermeable membrane from low to high solute concentration.

Chapter 4: Tissues and the Integumentary System

Basic Tissue Types and Functions

The human body is composed of four basic tissue types, each with specific functions and characteristics.

Tissue Type	Location	Structure	Function	Examples
Epithelial	Surfaces, linings	Tightly packed cells	Protection, secretion, absorption	Skin, glands
Connective	Throughout body	Scattered cells in matrix	Support, transport, storage	Bone, cartilage, blood
Muscle	Attached to bones, heart, walls of organs	Elongated cells (fibers)	Movement, contraction	Skeletal, cardiac, smooth muscle
Nervous	Brain, spinal cord, nerves	Neurons and glial cells	Communication, control	Nerve tissue

Specialized Tissue Functions

• Muscle Tissue: Responsible for movement and force generation (e.g., labor contractions).

• Cartilage Types: Hyaline, fibrocartilage, elastic cartilage; found in joints, ear, intervertebral discs.

• Intervertebral Discs: Composed of fibrocartilage; provide cushioning between vertebrae.

Integumentary System: Skin and Appendages

The skin is the largest organ, serving as a barrier and playing roles in homeostasis and vitamin D production.

• Layers of Skin: Epidermis (outer), dermis (middle), hypodermis (deepest).

• Skin Appendages: Glands (sebaceous, sweat), hair follicles.

• Homeostasis: Skin regulates temperature and water loss.

• Vitamin D Production: Skin synthesizes vitamin D when exposed to sunlight.

• Apocrine Glands: Located in armpits and groin; become active during puberty.

Example:

Sweat glands help cool the body through evaporation.