Chapter 1: Introduction

Levels of Organization

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

• 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

Organ Systems and Basic Functions

• There are 11 organ systems in the human body, each with specific functions (e.g., circulatory, respiratory, digestive).

Necessary Life Functions

• Maintaining boundaries, movement, responsiveness, digestion, metabolism, excretion, reproduction, and growth.

Survival Needs

• Nutrients, oxygen, water, normal body temperature, and appropriate atmospheric pressure.

Homeostasis

Homeostasis is the maintenance of a stable internal environment.

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

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

Anatomical Terms

• Orientation and directional terms: Describe locations of structures (e.g., anterior, posterior, superior, inferior).

• Regional terms: Specific areas within major body divisions.

Body Planes and Sections

• Sagittal plane: Divides body into right and left parts.

• Frontal (coronal) plane: Divides body into anterior and posterior parts.

• Transverse (horizontal) plane: Divides body into superior and inferior parts.

Body Cavities and Membranes

• Dorsal cavity: Cranial and vertebral cavities.

• Ventral cavity: Thoracic and abdominopelvic cavities.

• Membranes: Serous membranes line body cavities and cover organs.

Dividing the Abdominopelvic Region

• Can be divided into 4 quadrants or 9 regions for anatomical study.

Chapter 2: Chemistry

Matter and Energy

• Matter: Anything that occupies space and has mass.

• Energy: The capacity to do work; exists as kinetic or potential energy.

Elements of the Human Body

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

Atom Composition and Structure

• Protons: Positively charged particles in the nucleus.

• Neutrons: Neutral particles in the nucleus.

• Electrons: Negatively charged particles orbiting the nucleus.

• Atomic number: Number of protons.

• Atomic mass: Sum of protons and neutrons.

Isotopes

• Atoms with the same number of protons but different numbers of neutrons.

Mixtures

• Solutions: Homogeneous mixtures (e.g., saline).

• Colloids: Heterogeneous mixtures with larger particles (e.g., cytosol).

• Suspensions: Large particles that settle out (e.g., blood).

Valence Electrons and Bonding

• Valence electrons determine chemical reactivity and bonding.

Ionic Bonds

• Formed by transfer of electrons between atoms, creating anions (negative) and cations (positive).

Covalent Bonds

• Formed by sharing electrons between atoms; can be polar or nonpolar.

Electronegativity and Polar Covalent Bonds

• Electronegativity is an atom's ability to attract electrons; differences create polar bonds.

Hydrogen Bonds

• Weak attractions between hydrogen and electronegative atoms (e.g., in water).

Chemical Reactions

• Synthesis (anabolic) reactions: Build larger molecules from smaller ones.

• Decomposition (catabolic) reactions: Break down molecules.

• Exchange reactions: Involve both synthesis and decomposition.

Properties of Water

• High heat capacity, high heat of vaporization, polar solvent, reactivity, cushioning.

Acids and Bases

• Acids: Release H+ ions in solution.

• Bases: Accept H+ ions.

• pH: Measures hydrogen ion concentration:

• Buffers: Resist changes in pH.

Dehydration and Hydrolysis Reactions

• Dehydration: Removes water to form bonds.

• Hydrolysis: Adds water to break bonds.

Important Biomolecules

• Carbohydrates: Monosaccharides, disaccharides, polysaccharides (e.g., glucose, starch, glycogen).

• Lipids: Triglycerides, phospholipids, steroids; energy storage and membrane structure.

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

• Nucleic acids: DNA and RNA; genetic information and energy (ATP).

Protein Structure

• Primary, secondary, tertiary, and quaternary levels.

• Denaturation: Loss of structure and function.

Nucleic Acids

• DNA: Double helix, stores genetic information.

• RNA: Single-stranded, involved in protein synthesis.

• ATP: Energy currency of the cell.

• Nucleotide bases: Adenine, thymine, cytosine, guanine (uracil in RNA).

Chapter 3: The Cell

Cell Theory

• All living things are composed of cells; cells are the basic unit of life; all cells come from pre-existing cells.

Extracellular Material

• Substances outside cells, such as interstitial fluid, blood plasma, and extracellular matrix.

Plasma Membrane Composition and Structure

• Phospholipid bilayer with embedded proteins; controls entry and exit of substances.

• Receptors, enzymes, recognition, attachment, and joining functions.

Cell Junctions

• Tight junctions: Prevent leakage between cells.

• Desmosomes: Anchor cells together.

• Gap junctions: Allow communication between cells.

Passive Transport

• Diffusion: Movement of molecules from high to low concentration.

• Facilitated diffusion: Uses carrier or channel proteins.

• Osmosis: Diffusion of water across a membrane.

Active Transport

• Primary active transport: Direct use of ATP (e.g., sodium-potassium pump).

• Secondary active transport: Uses energy from ion gradients.

Vesicular Transport

• Endocytosis: Uptake of materials via vesicles (phagocytosis, pinocytosis, receptor-mediated).

• Exocytosis: Release of materials from the cell.

Osmolarity and Tonicity

• Osmolarity: Total solute concentration.

• Tonicity: Effect of solution on cell volume (isotonic, hypertonic, hypotonic).

Organelles

• Nucleus: Contains genetic material.

• Ribosomes: Protein synthesis.

• Rough ER: Protein modification.

• Smooth ER: Lipid synthesis.

• Golgi apparatus: Packaging and shipping.

• Lysosomes: Digestion.

• Peroxisomes: Detoxification.

• Mitochondria: ATP production via cellular respiration.

Cellular Respiration

• Glycolysis: Breakdown of glucose to pyruvate.

• Citric acid cycle: Produces ATP, NADH, FADH2.

• Electron transport chain: Produces most ATP via oxidative phosphorylation.

Cytoskeleton

• Microfilaments, intermediate filaments, microtubules; provide structure and transport.

Centrosomes and Centrioles

• Organize microtubules and are important in cell division.

Cell Cycle

• Interphase: G1, S, G2 phases (growth and DNA replication).

• M phase: Mitosis (PMAT: prophase, metaphase, anaphase, telophase) and cytokinesis.

Regulation of Cell Division

• Cyclins and cyclin-dependent kinases (CDKs): Control cell cycle progression.

Differences Between Mitosis and Meiosis

• Mitosis: Produces two identical diploid cells.

• Meiosis: Produces four genetically unique haploid gametes.

Autophagy, Proteosomes, Apoptosis

• Autophagy: Self-digestion of cell components.

• Proteosomes: Degrade unneeded or damaged proteins.

• Apoptosis: Programmed cell death.

STEM Cells and Progenitor Cells

• STEM cells: Undifferentiated cells with the potential to become various cell types.

• Progenitor cells: More limited than stem cells, but can differentiate into specific cell types.

Chapter 4: Tissues

Primary Germ Layers

• Ectoderm, mesoderm, endoderm: Embryonic layers that give rise to all tissues and organs.

Epithelial Tissue

• Properties: Covers surfaces, lines cavities, forms glands; avascular but innervated; high regenerative capacity.

• Classification: Based on layers (simple, stratified, pseudostratified) and cell shape (squamous, cuboidal, columnar).

• Function and location: Varies by type (e.g., simple squamous in lungs, stratified squamous in skin).

Glandular Epithelium

• Endocrine glands: Secrete hormones into blood.

• Exocrine glands: Secrete products into ducts (e.g., sweat, saliva).

• Unicellular glands: Mucous and goblet cells.

• Multicellular glands: Merocrine, holocrine, apocrine secretion.

Connective Tissue

• Main classes: Connective tissue proper, cartilage, bone, blood.

• Components: Ground substance, fibers (collagen, elastic, reticular), and cells.

• Function and location: Support, protection, insulation, transport.

Muscle Tissue

• Types: Skeletal (voluntary), cardiac (heart), smooth (walls of organs).

Nervous Tissue

• Composed of neurons and supporting cells; responsible for communication and control.

Covering and Lining Membranes

• Cutaneous membrane: Skin.

• Mucous membranes: Line body cavities open to the exterior.

• Serous membranes: Line closed body cavities.

Tissue Repair Steps

• Inflammation, organization (restores blood supply), regeneration and fibrosis (effect permanent repair).