ANP College Study Notes: Human Chapters 1-4 Body Orientation, Chemistry, Cells, and Tissues

Chapter 1 – The Human Body: Orientation & Homeostasis

Hierarchy of Structural Organization

The human body is organized in a hierarchical structure, from the simplest chemical level to the complex organism.

• Chemical Level: Atoms combine to form molecules.

• Cellular Level: Cells are made up of molecules.

• Tissue Level: Tissues consist of similar types of cells.

• Organ Level: Organs are made up of different types of tissues.

• Organ System Level: Organ systems consist of different organs that work together.

• Organismal Level: The human organism is made up of many organ systems.

Complementarity of Structure and Function

Structure determines function in the body. The shape and composition of a body part enable its specific function.

• Example: Bones are rigid to support and protect organs; lungs have thin walls for gas exchange.

Survival Needs of the Body

• Nutrients: Chemicals for energy and cell building.

• Oxygen: Required for metabolic reactions.

• Water: Most abundant chemical in the body; site of chemical reactions.

• Normal Body Temperature: Necessary for chemical reactions to occur at life-sustaining rates.

• Appropriate Atmospheric Pressure: Required for proper breathing and gas exchange.

Necessary Life Functions

• Maintaining Boundaries: Separation between internal and external environments (e.g., skin, plasma membrane).

• Movement: Muscular system allows movement of body and substances.

• Responsiveness: Ability to sense and respond to stimuli.

• Digestion: Breakdown of ingested food.

• Metabolism: All chemical reactions in the body.

• Excretion: Removal of wastes.

• Reproduction: Cellular and organismal reproduction.

• Growth: Increase in size and number of cells.

Homeostasis

Homeostasis is the maintenance of a stable internal environment despite external changes. Disruption leads to illness or disease.

• Example: Regulation of body temperature, blood glucose levels.

Feedback Systems

• Negative Feedback: Reverses the original stimulus (e.g., body temperature regulation).

• Positive Feedback: Amplifies the original stimulus (e.g., childbirth, blood clotting).

Components of a Feedback System:

• Receptor: Detects change.

• Control Center: Determines set point, analyzes input, coordinates response.

• Effector: Carries out response.

Anatomical Terms and Body Cavities

• Directional Terms: Superior, inferior, anterior, posterior, medial, lateral, proximal, distal.

• Body Cavities: Dorsal (cranial, vertebral), Ventral (thoracic, abdominopelvic).

Body Sections

• Transverse (Cross) Section: Divides body into superior and inferior parts.

• Frontal (Coronal) Section: Divides body into anterior and posterior parts.

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

Membranes

• Serous Membranes: Pleura (lungs), Pericardium (heart), Peritoneum (abdominopelvic organs).

• Parietal Layer: Lines cavity wall.

• Visceral Layer: Covers organ.

Chapter 2 – Basic Chemistry

Basic Definitions

• Atom: Smallest unit of an element.

• Molecule: Two or more atoms bonded together.

• Element: Pure substance of one type of atom.

• Energy: Capacity to do work.

• Mass: Amount of matter in an object.

• Matter: Anything that has mass and occupies space.

• Weight: Gravitational force acting on mass.

Atomic Structure

• Atomic Number: Number of protons in the nucleus.

• Mass Number: Number of protons plus neutrons.

• Valence Shell: Outermost electron shell; determines chemical reactivity.

Ions and Bonds

• Ion: Charged particle (gained or lost electrons).

• Cation: Positively charged (lost electron).

• Anion: Negatively charged (gained electron).

• Bicarbonate (HCO3-): Major buffer in blood.

• Ionic Bond: Electron transfer between atoms (e.g., NaCl).

• Covalent Bond: Electron sharing (e.g., H2O).

• Hydrogen Bond: Weak attraction between polar molecules (e.g., between water molecules).

Types of Mixtures

• Solution: Homogeneous mixture; solute particles do not settle (e.g., salt water).

• Colloid: Heterogeneous; appears mixed, scatters light (e.g., cytosol).

• Suspension: Heterogeneous; particles settle out (e.g., blood cells in plasma).

Chemical Reactions

• Synthesis Reaction: Building larger molecules from smaller ones (A + B → AB).

• Decomposition Reaction: Breaking down molecules (AB → A + B).

• Exchange Reaction: Parts are swapped (AB + CD → AD + CB).

Catabolic vs. Anabolic

• Catabolic: Breaking down molecules; releases energy.

• Anabolic: Building up molecules; requires energy.

Biomolecules

• Monosaccharide: Simple sugar (e.g., glucose).

• Disaccharide: Two sugars (e.g., sucrose).

• Polysaccharide: Many sugars (e.g., glycogen, starch).

• Protein: Made of amino acids; structure and function in cells.

DNA Structure

• Double Helix: Two strands coiled.

• Sugar-Phosphate Backbone: Sides of the ladder.

• Base Pairs: Adenine–Thymine (A–T), Cytosine–Guanine (C–G).

Transcription and Translation

• Transcription: DNA → mRNA (in nucleus).

• Translation: mRNA → protein (at ribosome).

• mRNA: Messenger; carries code from DNA.

• rRNA: Ribosomal; forms ribosome structure.

• tRNA: Transfer; brings amino acids to ribosome.

ATP (Adenosine Triphosphate)

• Where Made: Mitochondria.

• Structure: Adenine + ribose + 3 phosphates.

• Function: Main energy currency; energy released when last phosphate is removed.

Equation:

$\mathrm{ATP} \rightarrow \mathrm{ADP} + \mathrm{P_i} + \text{energy}$

pH and Buffers

• pH: Measure of hydrogen ion (H+) concentration.

• pH Scale: 0 (acidic) to 14 (basic); 7 is neutral.

• Normal Blood pH: 7.35–7.45.

• Buffer: Substance that resists pH change.

Equation:

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

Enzymes

• Function: Biological catalysts; speed up reactions by lowering activation energy.

• Example: Amylase breaks down starch.

Chapter 3 – Cells

Cell Theory

• All living things are made of cells.

• The cell is the basic unit of life.

• Cells arise from preexisting cells.

Cell Structure

• Plasma Membrane: Phospholipid bilayer; amphipathic (hydrophilic heads, hydrophobic tails).

• Fluid Mosaic Model: Proteins embedded and moving within the membrane.

• Cell Junctions: Tight junctions (seal), desmosomes (anchor), gap junctions (communication).

Intracellular Organelles

• Nucleus: Control center; contains DNA.

• Mitochondria: Site of ATP production.

• Ribosomes: Protein synthesis.

• Endoplasmic Reticulum (ER): Transport of materials (rough ER has ribosomes; smooth ER does not).

• Golgi Apparatus: Packaging and shipping of proteins and lipids.

• Lysosome: Digestion of cellular debris.

Transport Mechanisms

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

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

• Osmosis: Movement of water across membrane.

• Crenation: Cell shrinks in hypertonic solution.

• Lysis: Cell bursts in hypotonic solution.

• Na+/K+ Pump: 3 Na+ out, 2 K+ in per ATP hydrolyzed.

Vesicular Transport

• Endocytosis: Bulk transport into cell.

• Exocytosis: Bulk transport out of cell.

• Phagocytosis: "Cell eating"; engulfing large particles.

Mitosis and Cell Cycle

• Mitosis: Nuclear division; stages are Prophase, Metaphase, Anaphase, Telophase (PMAT).

• Cell Cycle: Interphase (G1, S, G2) and M phase (mitosis and cytokinesis).

Protein Structure Hierarchy

• Primary: Amino acid sequence.

• Secondary: Alpha helix or beta sheet.

• Tertiary: 3D folding of a single polypeptide.

• Quaternary: Multiple polypeptide chains.

Genetic Information Flow

• Transcription: DNA to mRNA in nucleus.

• Translation: mRNA to protein at ribosome.

• mRNA: Messenger RNA; carries code.

• rRNA: Ribosomal RNA; forms ribosome.

• tRNA: Transfer RNA; brings amino acids.

ATP

• Made in: Mitochondria.

• Structure: Adenine, ribose, three phosphates.

• Function: Energy for cellular work.

Chapter 4 – Tissues & Integument

Tissues: Definition, Study, Location, and Function

• Epithelial Tissue: Covers surfaces, lines cavities, forms glands.

• Connective Tissue: Supports, protects, binds other tissues (e.g., bone, blood, fat).

• Muscle Tissue: Contracts to cause movement (skeletal, cardiac, smooth).

• Nervous Tissue: Transmits electrical impulses.

Skin Structure

• Epidermis: Keratinized stratified squamous epithelium; protective barrier.

• Dermis: Connective tissue; provides strength and elasticity.

Inflammation: Signs and Tissue Repair

• Redness

• Heat

• Swelling

• Pain

These are the classic signs of inflammation following tissue injury.

Specialized Epithelia and Cartilage

• Transitional Epithelium: Found in the urinary bladder; allows stretching.

• Elastic Cartilage: Found in the external ear and epiglottis; provides flexibility.

Additional info: Where content was brief or listed, academic context and definitions were added for clarity and completeness. This guide covers foundational concepts for ANP college students, including structure, function, and examples for each topic.