Anatomy & Physiology Exam 1 Study Guide

Chapter 1: Introduction to Anatomy & Physiology

Anatomy, Physiology, and Their Relationship

Anatomy and physiology are closely related fields that study the structure and function of living organisms. Anatomy focuses on the physical structures, while physiology examines how these structures work together to sustain life.

• Anatomy: The study of body structures and their relationships.

• Physiology: The study of how body parts function and interact.

• Relationship: Structure determines function; changes in anatomy can affect physiological processes.

• Example: The structure of the heart (anatomy) enables it to pump blood (physiology).

Homeostasis

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

• Definition: The body's ability to maintain equilibrium by adjusting physiological processes.

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

• Feedback Mechanisms: Negative and positive feedback loops help maintain homeostasis.

Feedback Loops

Feedback loops are mechanisms that regulate physiological processes.

• Negative Feedback: Reduces the effect of a stimulus to restore balance (e.g., insulin lowering blood glucose).

• Positive Feedback: Enhances the effect of a stimulus (e.g., blood clotting).

• Equation: $\text{Response} = \text{Stimulus} \times \text{Feedback Factor}$

Body Systems

The human body is organized into systems that perform specific functions.

• Examples: Circulatory, respiratory, digestive, nervous, musculoskeletal systems.

• Integration: Systems work together to maintain homeostasis.

Planes and Regional Terms

Body planes and regional terms are used to describe locations and sections of the body.

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

• Regional Terms: Refers to specific areas (e.g., brachial = arm, femoral = thigh).

Chapter 2: Chemistry in Anatomy & Physiology

Atomic Structure

Atoms are the basic units of matter, composed of protons, neutrons, and electrons.

• 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 in an atom.

• Mass Number: Sum of protons and neutrons.

Types of Chemical Bonding

Chemical bonds hold atoms together in molecules and compounds.

• Ionic Bonds: Transfer of electrons between atoms (e.g., NaCl).

• Covalent Bonds: Sharing of electrons between atoms (e.g., H2O).

• Hydrogen Bonds: Weak attractions between polar molecules (e.g., between water molecules).

Acids and Bases

Acids and bases are substances that alter the concentration of hydrogen ions in a solution.

• Acid: Releases H+ ions; pH < 7.

• Base: Accepts H+ ions or releases OH-; pH > 7.

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

Organic vs. Inorganic Compounds

Compounds in the body are classified as organic or inorganic.

• Organic Compounds: Contain carbon; examples include carbohydrates, proteins, lipids, nucleic acids.

• Inorganic Compounds: Do not contain carbon; examples include water, salts, acids, bases.

Types of Reactions

Chemical reactions transform substances in the body.

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

• Decomposition: Breaking down molecules into smaller units (catabolism).

• Exchange: Rearrangement of parts between molecules.

• Equation: $\text{A} + \text{B} \rightarrow \text{AB}$ (synthesis)

Organic Macromolecules: Examples, Building Blocks, Bonds

Organic macromolecules are large, complex molecules essential for life.

• Carbohydrates: Monosaccharides; energy source.

• Proteins: Amino acids; structure and function.

• Lipids: Fatty acids and glycerol; energy storage.

• Nucleic Acids: Nucleotides; genetic information.

• Bonds: Glycosidic (carbohydrates), peptide (proteins), ester (lipids), phosphodiester (nucleic acids).

Enzyme Structure

Enzymes are biological catalysts that speed up chemical reactions.

• Structure: Proteins with specific active sites for substrates.

• Function: Lower activation energy, increase reaction rate.

• Equation: $\text{E} + \text{S} \rightarrow \text{ES} \rightarrow \text{E} + \text{P}$

Chapter 3: The Cell

Basic Cell Structure

Cells are the fundamental units of life, with specialized structures for various functions.

• Cell Membrane: Phospholipid bilayer controlling entry/exit of substances.

• Cytoplasm: Gel-like substance containing organelles.

• Nucleus: Contains genetic material (DNA).

Plasma Membrane Structure and Function

The plasma membrane maintains cellular integrity and regulates transport.

• Structure: Phospholipid bilayer with embedded proteins.

• Function: Selective permeability, communication, protection.

Cell Membrane Proteins

Proteins in the cell membrane perform various roles.

• Transport Proteins: Facilitate movement of substances.

• Receptor Proteins: Receive signals from the environment.

• Enzymatic Proteins: Catalyze reactions at the membrane.

Cell Junctions

Cell junctions connect cells and facilitate communication.

• Tight Junctions: Prevent leakage between cells.

• Desmosomes: Provide mechanical strength.

• Gap Junctions: Allow passage of ions and small molecules.

Organelles

Organelles are specialized structures within cells.

• Mitochondria: Produce ATP via cellular respiration.

• Endoplasmic Reticulum: Synthesizes proteins and lipids.

• Golgi Apparatus: Modifies and packages proteins.

• Lysosomes: Digest cellular waste.

Active and Passive Cellular Processes

Cells transport substances via active and passive mechanisms.

• Passive Transport: No energy required; includes diffusion, osmosis, facilitated diffusion.

• Active Transport: Requires energy (ATP); moves substances against concentration gradient.

• Equation: $\text{Rate of diffusion} \propto \text{Concentration gradient}$

Hypotonic and Hypertonic Solutions

Solutions affect cell volume based on their osmolarity relative to the cell.

• Hypotonic: Lower solute concentration than cell; water enters cell, may cause swelling.

• Hypertonic: Higher solute concentration than cell; water leaves cell, may cause shrinkage.

• Isotonic: Equal solute concentration; no net water movement.

Transport and Mitosis

Cells transport materials and divide to reproduce and grow.

• Transport: Includes endocytosis, exocytosis, and vesicular transport.

• Mitosis: Process of cell division resulting in two identical daughter cells.

• Stages of Mitosis: Prophase, metaphase, anaphase, telophase.

• Equation: $\text{2n} \rightarrow \text{2n} + \text{2n}$ (where n = chromosome number)