Anatomy & Physiology: Foundational Concepts and Study Guide

Introduction to Anatomy & Physiology

Definitions and Relationships

Anatomy and physiology are foundational sciences in understanding the human body. Anatomy is the study of the structure of body parts and their relationships to one another, while physiology is the study of the function of the body and its parts. These disciplines are closely related because the structure of a body part often determines its function.

• Anatomy: Focuses on morphology, including organs, tissues, and cells.

• Physiology: Explores how anatomical structures work individually and together to sustain life.

• Importance: Studying both together helps us understand how the body works and how structure supports function.

Hierarchy of Structural Organization

The human body is organized in a hierarchical manner, from the smallest to the largest structures:

• Chemical level: Atoms and molecules

• Cellular level: Cells and their organelles

• Tissue level: Groups of similar cells

• Organ level: Contains two or more types of tissues

• Organ system level: Organs that work closely together

• Organismal level: All organ systems combined to make the whole organism

Basic Life Functions

For something to be considered alive, it must perform certain functions:

• Maintaining boundaries

• Movement

• Responsiveness

• Digestion

• Metabolism

• Excretion

• Reproduction

• Growth

Homeostasis

Homeostasis is the maintenance of a stable internal environment despite changes in the external environment. It is vital for normal body functioning and sustaining life.

• Positive feedback: Enhances the original stimulus (e.g., blood clotting, labor contractions).

• Negative feedback: Reduces or shuts off the original stimulus (e.g., regulation of body temperature, blood glucose levels).

Directional and Regional Terms

Understanding anatomical terminology is essential for describing locations and relationships of body parts. Directional terms (such as anterior, posterior, superior, inferior) and regional terms (such as thoracic, abdominal) are used to describe positions and regions of the body.

Basic Chemistry for Anatomy & Physiology

Energy and Matter

• Energy: The capacity to do work. Types include potential energy (stored) and kinetic energy (in motion).

• Forms of energy: Chemical, electrical, mechanical, and radiant.

Atoms and Elements

• Atoms: The smallest unit of matter, composed of protons, neutrons, and electrons.

• Proton: Positively charged particle in the nucleus.

• Neutron: Neutral particle in the nucleus.

• Electron: Negatively charged particle orbiting the nucleus.

• 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.

• Atomic weight: Average mass of all isotopes of an element.

Molecules and Compounds

• Molecule: Two or more atoms bonded together.

• Compound: Two or more different atoms bonded together.

• Mixtures: Physical combinations of matter (solutions, colloids, suspensions).

Chemical Bonds

• Ionic bonds: Transfer of electrons between atoms (e.g., NaCl).

• Covalent bonds: Sharing of electrons between atoms.

• Polar covalent: Unequal sharing of electrons.

• Nonpolar covalent: Equal sharing of electrons.

• Hydrogen bonds: Weak attractions between polar molecules.

Chemical Reactions

• Synthesis (anabolic) reactions: Atoms or molecules combine to form a larger, more complex molecule.

• Decomposition (catabolic) reactions: Molecule is broken down into smaller molecules or atoms.

• Exchange reactions: Involve both synthesis and decomposition.

• Redox reactions: Involve the transfer of electrons between atoms.

• Hydrolysis: Addition of water to break bonds.

Factors Affecting Chemical Reactions

• Temperature

• Concentration of reactants

• Particle size

• Catalysts (e.g., enzymes)

Biological Macromolecules

Carbohydrates

• Monomers: Monosaccharides (e.g., glucose, fructose)

• Disaccharides: Two monosaccharides joined (e.g., sucrose, lactose)

• Polysaccharides: Many monosaccharides (e.g., glycogen, starch)

• Functions: Primary energy source for cells

Lipids

• Functions: Energy storage, insulation, cell membrane structure

• Types: Triglycerides, phospholipids, steroids

• Saturated vs. Unsaturated: Saturated fats have no double bonds; unsaturated have one or more double bonds

• Phospholipids: Major component of cell membranes

Proteins

• Monomers: Amino acids

• Peptide bonds: Link amino acids

• Structure: Primary, secondary, tertiary, and quaternary levels

• Fibrous proteins: Structural (e.g., collagen, keratin)

• Globular proteins: Functional (e.g., enzymes, antibodies)

Nucleic Acids

• Monomers: Nucleotides

• Types: DNA and RNA

• ATP: Adenosine triphosphate, the energy currency of the cell

• Differences between DNA and RNA: DNA is double-stranded, contains deoxyribose; RNA is single-stranded, contains ribose

Cell Structure and Function

Cell Theory and Features

• All living things are composed of cells

• Cells are the basic unit of life

• Cells arise from pre-existing cells

Plasma Membrane

• Structure: Phospholipid bilayer with embedded proteins

• Functions: Selective barrier, communication, cell recognition

Membrane Transport

• Passive transport: No energy required (diffusion, osmosis, facilitated diffusion)

• Active transport: Requires energy (e.g., Na+/K+ ATPase pump)

• Vesicular transport: Endocytosis, exocytosis, transcytosis

Cellular Organelles

• Mitochondria: Site of ATP production

• Ribosomes: Protein synthesis

• Endoplasmic reticulum: Smooth (lipid synthesis), rough (protein synthesis)

• Golgi apparatus: Modifies, sorts, and packages proteins

• Lysosomes: Digestive enzymes

• Peroxisomes: Detoxification

• Cytoskeleton: Structural support

Cell Division

• Mitosis: Division of the nucleus (phases: prophase, metaphase, anaphase, telophase)

• Cytokinesis: Division of the cytoplasm

Cell Death and Development

• Apoptosis: Programmed cell death

• Development: Cells develop from embryo to adult through differentiation

Tissues and Organ Systems

Epithelial Tissue

• Functions: Protection, absorption, filtration, secretion

• Classification: By cell shape (squamous, cuboidal, columnar) and layers (simple, stratified)

• Glands: Exocrine (secrete onto surfaces), endocrine (secrete into blood)

Connective Tissue

• Functions: Support, protection, insulation, transport

• Types: Loose, dense, cartilage, bone, blood

Muscle Tissue

• Types: Skeletal, cardiac, smooth

• Functions: Movement, posture, heat production

Nervous Tissue

• Cells: Neurons and neuroglia

• Function: Transmit electrical impulses for communication

Membranes

• Cutaneous membrane: Skin

• Mucous membrane: Lines body cavities open to the exterior

• Serous membrane: Lines closed body cavities

Sample Table: Types of Chemical Bonds

Bond Type	Description	Example
Ionic	Transfer of electrons	NaCl
Covalent (Polar)	Unequal sharing of electrons	H2O
Covalent (Nonpolar)	Equal sharing of electrons	O2
Hydrogen	Weak attraction between polar molecules	Between water molecules

Key Equations

• Concentration (percent): $\text{Percent} = \frac{\text{Solute mass}}{\text{Solution mass}} \times 100$

• Atomic weight: $\text{Atomic weight} = \sum (\text{isotope mass} \times \text{fractional abundance})$

Additional info:

• Some content was inferred and expanded for clarity and completeness based on standard Anatomy & Physiology curricula.