Fundamental Concepts in Anatomy & Physiology: Study Guide

1. Homeostasis and Feedback Mechanisms

Negative Feedback & Positive Feedback

Homeostasis is the maintenance of a stable internal environment. Feedback mechanisms regulate physiological processes:

• Negative Feedback: A process that reverses a change to keep a variable within a set range. Example: Body temperature regulation.

• Positive Feedback: A process that amplifies a change, moving the system away from its starting state. Example: Blood clotting.

2. Levels of Organization

Hierarchical Structure of the Human Body

The human body is organized into increasing levels of complexity:

• Chemical Level: Atoms and molecules

• Cellular Level: Cells and their organelles

• Tissue Level: Groups of similar cells

• Organ Level: Structures composed of different tissues

• Organ System Level: Groups of organs working together

• Organism Level: The complete living being

3. Anatomical Position and Body Planes

Standard Reference and Sectional Anatomy

• Anatomical Position: Standing upright, facing forward, arms at sides, palms facing forward.

• Sagittal Plane: Divides the body into left and right parts.

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

• Transverse Plane: Divides the body into superior and inferior parts.

4. Serous Membranes

Pleura and Pericardium

• Pleura: Serous membrane surrounding the lungs.

• Pericardium: Serous membrane surrounding the heart.

5. Abdominal Pelvic Regions

Regional Anatomy

• Abdominal Regions: Nine regions used to describe locations in the abdomen (e.g., epigastric, umbilical, hypogastric).

6. Characteristics of Life

Defining Living Organisms

• Organization

• Metabolism

• Responsiveness

• Growth

• Development

• Reproduction

7. Anatomy vs. Physiology

Structure and Function

• Anatomy: Study of body structure.

• Physiology: Study of body function.

8. Elements in the Human Body

Major Elements and Energy Levels

• Major Elements: Oxygen, carbon, hydrogen, nitrogen.

• Energy Levels: Electrons occupy energy levels (shells) around the nucleus.

9. Carbohydrates

Glucose and Glycogen

• Glucose: Simple sugar, primary energy source.

• Glycogen: Storage form of glucose in animals.

10. Chemical Bonds and Molecules

Organic vs. Inorganic Molecules

• Organic Molecules: Contain carbon and hydrogen (e.g., carbohydrates, proteins).

• Inorganic Molecules: Do not contain both carbon and hydrogen (e.g., water, salts).

11. Chemical Reactions

Anabolic vs. Catabolic

• Anabolic (Synthesis): Building larger molecules from smaller ones.

• Catabolic (Hydrolysis): Breaking down larger molecules into smaller ones.

12. Important Chemical Formulas

Water and Ions

• Water: $H_2O$

• Hydrogen Ion: $H^+$

• Hydroxide Ion: $OH^-$

13. Valence Electrons and Chemical Formulas

Calculating Valence Electrons

• Valence electrons are found in the outermost shell of an atom.

• Example: $H_2O$ has 2 hydrogen atoms (1 electron each) and 1 oxygen atom (8 electrons, 6 in valence shell).

14. DNA and RNA

Structure and Function

• DNA: Deoxyribonucleic acid, stores genetic information.

• RNA: Ribonucleic acid, involved in protein synthesis.

• Nucleotides: Building blocks of DNA and RNA, consist of a sugar, phosphate, and nitrogenous base.

15. Solutions and Tonicity

Isotonic, Hypotonic, Hypertonic

• Isotonic: Same solute concentration as the cell; no net water movement.

• Hypotonic: Lower solute concentration than the cell; water enters cell.

• Hypertonic: Higher solute concentration than the cell; water leaves cell.

16. Plasma Membrane Components

Structure and Function

• Phospholipids: Form the bilayer.

• Proteins: Serve as channels, carriers, receptors.

• Carbohydrates: Attach to proteins/lipids for cell recognition.

17. Biological Macromolecules

Carbohydrates, Proteins, Lipids, Nucleic Acids

• Carbohydrates: Monosaccharides, disaccharides, polysaccharides.

• Proteins: Made of amino acids; perform structural and functional roles.

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

• Nucleic Acids: DNA and RNA; store and transmit genetic information.

18. Cell Division

Mitosis and Interphase

• Mitosis: Division of the nucleus; stages include prophase, metaphase, anaphase, telophase.

• Interphase: Period of cell growth and DNA replication.

19. Cell Organelles

Structure and Function

• Nucleus: Contains genetic material.

• Mitochondria: Site of ATP production.

• Golgi Apparatus: Modifies and packages proteins.

• Ribosomes: Protein synthesis.

• Endoplasmic Reticulum: Synthesis and transport of proteins/lipids.

20. Cellular Processes

Transport and Energy

• Active Transport: Requires ATP to move substances against concentration gradient.

• Phagocytosis: Cell engulfs particles.

• Exocytosis: Expulsion of materials from the cell.

• Receptor-Mediated Endocytosis: Specific uptake of molecules via receptors.

21. Atomic Structure

Atomic Number and Mass

• Atomic Number: Number of protons in the nucleus.

• Atomic Mass: Sum of protons and neutrons.

22. Body Cavities

Major Cavities of the Human Body

• Cranial Cavity: Contains the brain.

• Thoracic Cavity: Contains heart and lungs.

• Abdominal Cavity: Contains digestive organs.

• Pelvic Cavity: Contains reproductive organs.

23. Table: Comparison of Solution Types

Solution Type	Solute Concentration	Effect on Cell
Isotonic	Equal to cell	No net water movement
Hypotonic	Lower than cell	Cell swells (water enters)
Hypertonic	Higher than cell	Cell shrinks (water leaves)

24. Table: Major Biological Macromolecules

Macromolecule	Monomer	Function
Carbohydrate	Monosaccharide	Energy source, structure
Protein	Amino acid	Structure, enzymes, transport
Lipid	Fatty acid, glycerol	Energy storage, membranes
Nucleic Acid	Nucleotide	Genetic information

Additional info: Some explanations and examples have been expanded for clarity and completeness.