Anatomy & Physiology: Foundations, Chemistry, Cells, and Tissues (Chapters 1–4) – Study Notes

Ch. 1: Introduction to Anatomy & Physiology

Levels of Complexity

The human body is organized into hierarchical levels, each increasing in complexity.

• Chemical Level: Atoms and molecules essential for life.

• Cellular Level: Basic structural and functional units (cells).

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

• Organ Level: Structures composed of two or more tissue types.

• Organ System Level: Groups of organs working together for a common purpose.

• Organismal Level: The complete living being.

Example: Muscle cells (cellular) form muscle tissue (tissue), which makes up the heart (organ), part of the cardiovascular system (organ system).

Life Functions

• Maintaining boundaries (e.g., cell membranes, skin)

• Movement (muscle contraction, locomotion)

• Responsiveness (ability to sense and respond to stimuli)

• Digestion (breaking down food for absorption)

• Metabolism (all chemical reactions in the body)

• Excretion (removal of wastes)

• Reproduction (cellular and organismal levels)

• Growth (increase in size and number of cells)

Survival Needs

• Nutrients

• Oxygen

• Water

• Normal body temperature

• Appropriate atmospheric pressure

Directional Terminology & Body Planes

• Directional Terms: Describe positions (e.g., superior, inferior, anterior, posterior, medial, lateral, proximal, distal).

• Body Planes: Imaginary lines dividing the body (sagittal, frontal/coronal, transverse/horizontal).

Body Regions (Landmarks)

• Specific areas used to describe locations (e.g., abdominal, thoracic, cranial).

Homeostasis

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

• Involves dynamic equilibrium and feedback mechanisms.

Positive and Negative Feedback

• Negative Feedback: Reduces the effect of the stimulus (e.g., body temperature regulation).

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

Ch. 2: Basic Chemistry for Anatomy & Physiology

Energy Types

Energy is the capacity to do work. Types include:

• Chemical energy: Stored in bonds of chemical substances.

• Electrical energy: Movement of charged particles.

• Mechanical energy: Directly involved in moving matter.

• Radiant energy: Energy traveling in waves (e.g., light).

Atomic Structure

• Protons: Positively charged, in nucleus.

• Neutrons: No charge, in nucleus.

• Electrons: Negatively charged, orbit nucleus.

Atomic number = number of protons. Atomic mass = protons + neutrons. Atomic weight = average mass of all isotopes.

Major Body Elements

• Oxygen (O), Carbon (C), Hydrogen (H), Nitrogen (N) are most abundant.

Mixtures: Solution, Colloid, Suspension

• Solution: Homogeneous mixture (e.g., salt water).

• Colloid: Heterogeneous, particles do not settle (e.g., cytosol).

• Suspension: Heterogeneous, particles settle (e.g., blood).

Chemical Bonds

• Covalent bonds: Sharing of electrons.

• Ionic bonds: Transfer of electrons, forming ions.

• Polar bonds: Unequal sharing of electrons.

Factors Influencing Chemical Reactions

• Heat (temperature), catalysts (e.g., enzymes), concentration of reactants.

Acids, Bases, and pH

• Acids: Release H+ ions.

• Bases: Accept H+ ions.

• pH scale: Measures hydrogen ion concentration.

$\text{pH} = -\log_{10}[\text{H}^+]$

Ch. 3: The Cell

Cell Structure Diagram & Components

• Cytoskeleton: Network of protein filaments for shape and movement.

• Cilia: Hair-like projections for movement.

• Microfilaments, Microtubules, Microvilli: Structural and functional support.

• DNA, Chromosome, Nucleus, Nuclear Envelope, Nucleolus: Genetic material and control center.

• Cytosol: Fluid portion of cytoplasm.

• Centrosome: Organizes microtubules.

• Basement Membrane: Supports epithelial tissue.

Cell Organelles

• Lysosome: Digests waste.

• Smooth ER: Lipid synthesis.

• Rough ER: Protein synthesis (with ribosomes).

• Centriole: Cell division.

• Mitochondrion: ATP production.

• Ribosome: Protein synthesis.

• Golgi Apparatus: Modifies and packages proteins.

• Peroxisome: Breaks down fatty acids and detoxifies.

Cell Cycle

• Interphase: Cell growth and DNA replication.

• Mitosis: Division of nucleus.

  • Prophase

  • Metaphase

  • Anaphase

  • Telophase

• Cytokinesis: Division of cytoplasm.

Membrane Transport

• Exocytosis: Vesicles release contents outside cell.

• Endocytosis: Cell engulfs material.

• Passive Transport: No energy required (e.g., diffusion, osmosis).

• Active Transport: Requires energy (ATP).

Membrane Junctions

• Tight Junction: Prevents leakage between cells.

• Gap Junction: Allows communication between cells.

• Desmosome: Provides mechanical strength.

DNA Replication, Transcription, Translation

• DNA Replication: Copying DNA before cell division.

• Transcription: DNA to mRNA in nucleus.

• Translation: mRNA to protein at ribosome.

Ch. 4: Tissues

Tissue Identification

• Simple squamous epithelium

• Stratified squamous epithelium

• Simple cuboidal epithelium

• Pseudostratified columnar epithelium

• Adipose tissue

• Reticular tissue

• Dense regular connective tissue

• Dense irregular connective tissue

• Elastic tissue

• Hyaline cartilage

• Elastic cartilage

• Fibrocartilage

• Blood

• Compact bone

• Skeletal muscle

• Cardiac muscle

• Smooth muscle

• Nervous tissue

Tissue Functions, Descriptions, and Locations

• Functions: Protection, absorption, secretion, support, movement, transmission of impulses.

• Descriptions: Based on cell shape, arrangement, and matrix.

• Locations: Vary by tissue type (e.g., epithelium lines surfaces, muscle in organs, nervous in brain/spinal cord).

Tissue Classifications

• Connective Tissue: Supports, binds, protects (e.g., bone, blood, cartilage).

• Epithelium: Covers surfaces, lines cavities.

• Muscle: Movement (skeletal, cardiac, smooth).

• Nervous Tissue: Transmits electrical impulses.

Additional info: For each tissue type, students should be able to recognize histological features and relate structure to function.