Anatomy & Physiology: Foundational Concepts and Cellular Processes Study Guide

Chapter 1: Introduction to Anatomy & Physiology

Defining Anatomy and Physiology

Anatomy and physiology are foundational sciences in understanding the human body. Anatomy focuses on the structure of body parts, while physiology explores their functions.

• Anatomy: The study of the structure and relationships between body parts.

• Physiology: The study of the function of body parts and the body as a whole.

• Scientific Method: Involves hypothesis, fact, law, and theory. Hypothesis is a testable prediction; fact is an observation; law is a statement based on repeated experimental observations; theory is a well-substantiated explanation.

Levels of Human Structure

The human body is organized from the simplest to the most complex levels.

• Chemical Level → Cellular Level → Tissue Level → Organ Level → Organ System Level → Organism Level

• Example: Atoms → Molecules → Cells → Tissues → Organs → Organ Systems → Human Body

Homeostasis

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

• Mechanisms: Negative feedback (reduces change), positive feedback (amplifies change).

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

• Negative Feedback: Example: Body temperature regulation. Importance: Maintains stability.

• Positive Feedback: Example: Blood clotting, childbirth. Importance: Drives processes to completion.

Anatomical Position and Directional Terms

Standard anatomical position is standing upright, facing forward, arms at sides, palms forward.

• Directional Terms: Used to describe locations of structures.

• Examples:

  • Caudal: Toward the tail

  • Cranial: Toward the head

  • Anterior (ventral): Front

  • Posterior (dorsal): Back

  • Medial: Toward the midline

  • Lateral: Away from the midline

  • Proximal: Closer to the point of attachment

  • Distal: Farther from the point of attachment

  • Superficial: Toward the surface

  • Deep: Away from the surface

• Planes of the Body:

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

  • Sagittal: Divides body into left and right

  • Transverse: Divides body into superior and inferior

  • Oblique: Cuts at an angle

Chapter 2: Chemical Basis of Life

Properties of Water

Water is essential for life due to its unique chemical and physical properties.

• Cohesion: Water molecules stick together.

• Adhesion: Water molecules stick to other surfaces.

• High Heat of Vaporization: Requires significant energy to change from liquid to gas.

• Hydrogen Bonding: Responsible for many properties of water.

Atoms and Elements

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

• Atomic Number: Number of protons in the nucleus.

• Atomic Mass: Sum of protons and neutrons.

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

• Valence Electrons: Electrons in the outer shell, important for chemical bonding.

Molecules and Chemical Bonds

Molecules are formed by atoms bonded together. The type of bond affects molecular properties.

• Ionic Bonds: Transfer of electrons between atoms.

• Covalent Bonds: Sharing of electrons between atoms.

• Polar vs. Nonpolar Molecules: Polar molecules have unequal sharing of electrons; nonpolar have equal sharing.

Acids, Bases, and Buffers

Acids and bases are important in maintaining pH balance in the body. Buffers help stabilize pH.

• Acid: Substance that releases hydrogen ions ($H^+$).

• Base: Substance that accepts hydrogen ions.

• Buffer: Solution that resists changes in pH.

• pH Scale: Measures acidity or alkalinity. $pH = -\log[H^+]$

Organic Molecules

Organic molecules contain carbon and are essential for life. Four major groups exist.

• Carbohydrates: Provide energy; made of monosaccharides.

• Lipids: Store energy, form cell membranes.

• Proteins: Made of amino acids; perform various functions.

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

Macromolecule Structure and Function

Macromolecules have unique structures that determine their functions.

• Protein Structure: Four levels: primary, secondary, tertiary, quaternary.

• Denaturation: Loss of structure and function due to environmental changes.

• Hydrophilic vs. Hydrophobic: Hydrophilic molecules interact with water; hydrophobic do not.

Chapter 3: Cellular Structure and Function

The Cell Theory

The cell theory is a fundamental concept in biology, stating:

• All living things are composed of cells.

• The cell is the basic unit of life.

• All cells arise from pre-existing cells.

Cell Membrane Structure and Function

The cell membrane controls the movement of substances in and out of the cell.

• Major Parts: Phospholipid bilayer, proteins, carbohydrates, cholesterol.

• Specialized Structures: Microvilli (increase surface area), cilia (movement), flagella (locomotion).

Membrane Transport

Cells use various mechanisms to transport substances across membranes.

• Passive Transport: No energy required. Includes:

  • Diffusion

  • Facilitated Diffusion

  • Osmosis

• Active Transport: Requires energy (ATP). Includes:

  • Pumps

  • Endocytosis

  • Exocytosis

Organelles: Structure and Function

Organelles are specialized structures within cells that perform specific functions.

• Cytoplasm: Region between the cell membrane and nucleus.

• Membranous Organelles: Surrounded by membranes (e.g., mitochondria, endoplasmic reticulum).

• Non-membranous Organelles: Not surrounded by membranes (e.g., ribosomes, cytoskeleton).

Protein Synthesis

Protein synthesis involves transcription and translation.

• Transcription: DNA is copied into mRNA in the nucleus.

• Translation: mRNA is used to assemble amino acids into proteins at ribosomes.

Cell Cycle and Mitosis

The cell cycle consists of phases that prepare a cell for division.

• Main Phases: Interphase (growth, DNA replication), Mitosis (division).

• Mitosis Stages: Prophase, Metaphase, Anaphase, Telophase.

• Chromosomes: Structures containing DNA; number varies between species.

• Centromere: Region where sister chromatids are joined.

Cancer Biology

Cancer is uncontrolled cell growth. It can be benign (non-spreading) or malignant (spreading).

• Metastasis: Spread of cancer cells to other parts of the body.

DNA Replication

DNA replication is the process by which DNA makes a copy of itself during cell division.

• Key Steps: Unwinding of DNA, pairing of nucleotides, formation of new strands.

• Importance: Ensures genetic information is passed to daughter cells.

Macromolecule	Monomer	Function	Example
Carbohydrate	Monosaccharide	Energy source	Glucose
Lipid	Fatty acid, glycerol	Energy storage, membrane structure	Triglyceride
Protein	Amino acid	Enzymes, structure, transport	Hemoglobin
Nucleic Acid	Nucleotide	Genetic information	DNA

Additional info: Academic context and examples have been added to expand on brief points and ensure completeness for exam preparation.