Chapter 1: Introduction to Anatomy and Physiology

Definitions and Scope

Anatomy and physiology are foundational sciences in understanding the human body. Anatomy is the study of internal and external structures, while physiology focuses on the functions of living organisms and their parts.

• Anatomy: Study of body structure (e.g., organs, tissues, cells).

• Physiology: Study of body function (e.g., how organs work together).

• Both disciplines are interdependent for a full understanding of the human body.

Types of Anatomy

• Gross (macroscopic) anatomy: Study of structures visible to the naked eye (e.g., organs, muscles).

• Microscopic anatomy: Study of structures only visible under a microscope (e.g., cells, tissues).

• Surface anatomy: Study of external features and their relation to deeper structures.

• Histology: Study of tissues.

• Cytology: Study of cells.

Types of Physiology

• Cell physiology: Chemical processes within and between cells.

• Systemic physiology: Function of organ systems (e.g., cardiovascular physiology).

Hierarchy of Structural Organization

The body is organized from simplest to most complex:

• Atoms → molecules → cells → tissues → organs → organ systems → organism

Organ Systems Overview

There are 11 organ systems in the human body, each with specific functions:

• Integumentary system: Skin, protection, temperature regulation.

• Skeletal system: Support, protection, blood cell production.

• Muscular system: Movement, posture, heat production.

• Nervous system: Fast-acting control, response to stimuli.

• Endocrine system: Hormone production, long-term regulation.

• Cardiovascular system: Transport of nutrients, gases, wastes.

• Lymphatic system: Immunity, fluid balance.

• Respiratory system: Gas exchange.

• Digestive system: Breakdown and absorption of nutrients.

• Urinary system: Waste elimination, water balance.

• Reproductive system: Production of offspring.

Homeostasis

All organ systems are interdependent and work together to maintain a stable internal environment, known as homeostasis.

• Intrinsic (autoregulation): Local, automatic adjustment by cells or organs.

• Extrinsic regulation: Involves nervous and endocrine systems for broader control.

Feedback Mechanisms

• Negative feedback: Opposes change to maintain stability (e.g., body temperature, blood pressure).

• Positive feedback: Enhances change (e.g., blood clotting, labor contractions).

Body Regions and Cavities

• Abdominopelvic quadrants: RUQ, LUQ, RLQ, LLQ.

• Abdominopelvic regions: Right/left hypochondriac, epigastric, right/left lumbar, umbilical, right/left iliac, hypogastric.

• Main body cavities: Thoracic (contains heart, lungs), abdominopelvic (digestive, urinary, reproductive organs).

• Mediastinum: Central thoracic compartment containing heart, trachea, esophagus.

Directional and Sectional Terms

• Anterior (ventral): Front

• Posterior (dorsal): Back

• Lateral: Away from midline

• Medial: Toward midline

• Proximal: Closer to trunk

• Distal: Farther from trunk

• Superficial: Toward surface

• Deep: Away from surface

• Planes: Sagittal (left/right), coronal/frontal (anterior/posterior), transverse (superior/inferior).

Imaging Techniques

• X-rays, ultrasound, CT, MRI, PET: Used to visualize internal structures.

• Angiography: Visualizes blood vessels.

Chapter 2: Chemistry of Life

Atoms, Ions, and Isotopes

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

• Ions: Atoms that have gained or lost electrons (cations = positive, anions = negative).

Chemical Bonds

• Ionic bonds: Transfer of electrons from one atom to another.

• 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 (e.g., water).

Chemical Reactions

• Synthesis:

• Decomposition:

• Exchange:

• Reversible:

• Exergonic: Releases energy

• Endergonic: Absorbs energy

Enzymes

• Enzymes: Biological catalysts that lower activation energy and speed up reactions.

• Enzymes are not changed or consumed during reactions.

Water, pH, and Buffers

• Water: Universal solvent, involved in many body reactions.

• pH: Measures hydrogen ion concentration;

• pH scale: 0 (acidic) to 14 (basic), 7 is neutral.

• Buffers: Compounds that stabilize pH by removing or replacing H+ ions.

Biological Molecules

• Carbohydrates: Sugars and starches; main energy source (e.g., glucose).

• Lipids: Fats, oils, steroids; energy storage, insulation, hormones.

• Proteins: Chains of amino acids; structure, enzymes, transport.

• Nucleic acids: DNA and RNA; genetic information.

Examples and Applications

• Glycogen: Storage form of glucose in liver and muscle.

• Fatty acids: Saturated (single bonds) vs. unsaturated (double bonds).

• Steroids: Hormones (e.g., estrogen, testosterone), cholesterol.

• Hydrogen bonding: Stabilizes protein secondary structure (alpha-helix, beta-sheet).

Chapter 3: The Cell and Cellular Processes

Cell Structure and Function

• Plasma membrane: Selectively permeable barrier; regulates entry/exit of substances.

• Cytoplasm: Contains organelles and cytosol.

• Mitochondria: Site of ATP production (aerobic respiration).

• Ribosomes: Protein synthesis.

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

• Golgi apparatus: Modifies, sorts, packages proteins/lipids.

• Lysosomes: Digestive enzymes for breakdown of waste.

• Microfilaments and microtubules: Cytoskeleton components; microtubules made of tubulin.

• Nucleus: Contains DNA, controls cell activities.

Genetic Material and Protein Synthesis

• DNA: Double helix, antiparallel strands, complementary base pairing (A-T, C-G).

• RNA: Single-stranded, uracil replaces thymine.

• Transcription: DNA → mRNA in nucleus.

• Translation: mRNA → protein at ribosome.

• Codon: Three-base sequence on mRNA coding for amino acids.

• ATP (adenosine triphosphate): Main energy currency of the cell.

Cell Division

• Mitosis: Division of somatic cells; produces two identical daughter cells.

• Meiosis: Division of sex cells; produces four genetically unique gametes.

• Chromosomes: DNA tightly coiled; humans have 46 (23 pairs).

• Diploid: Two sets of chromosomes (somatic cells).

• Haploid: One set of chromosomes (gametes).

Membrane Transport

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

• Active transport: Requires energy (e.g., sodium-potassium pump).

• Endocytosis: Cell engulfs material.

• Exocytosis: Cell expels material.

Cell Death and Cancer

• Autolysis: Destruction of cell from within (cell damage or injury).

• Apoptosis: Genetically programmed cell death.

• Tumors: Abnormal cell growth; benign (localized), malignant (invasive, can metastasize).

Summary Table: Types of Membrane Transport

Additional info:

• Some explanations and examples have been expanded for clarity and completeness.

• Table entries and some definitions are inferred from standard Anatomy & Physiology curriculum.