Anatomy & Physiology: Foundational Concepts and Cellular Structure Study Notes

Chapter 1: Introduction to Anatomy and Physiology

Key Terminology

• Anatomy: The study of the structure of body parts and their relationships to one another.

• Physiology: The study of the function of body parts and how they work to carry out life-sustaining activities.

• Cranial, Diffusion, Equilibrium, Feedback, Effector, Inferior, Lateral, Transverse Plane, Organ, Physiology, Posterior, Sagittal Plane, Contralateral, Pericardium, Ventral Body Cavity: These terms describe anatomical directions, body cavities, and physiological processes essential for understanding the human body.

Major Concepts

• Difference between Anatomy and Physiology: Anatomy focuses on structure, while physiology focuses on function. For example, the heart's anatomy includes its chambers and valves, while its physiology involves pumping blood.

• Structure-Function Relationship: The structure of a body part often determines its function. For instance, the thin walls of alveoli in the lungs facilitate gas exchange.

• Levels of Organization: The human body is organized from molecules to cells, tissues, organs, organ systems, and the organism.

• Directional Terms: Terms such as anterior, posterior, medial, lateral, proximal, and distal describe locations and relationships between body parts.

• Body Cavities: The body contains several cavities (cranial, thoracic, abdominal, pelvic) that house organs.

• Planes of the Body: The sagittal, frontal (coronal), and transverse planes divide the body for anatomical study.

• Membranes: Parietal membranes line body cavities, while visceral membranes cover organs. For example, the parietal pericardium lines the pericardial cavity, and the visceral pericardium covers the heart.

• Homeostasis: The maintenance of a stable internal environment. Feedback mechanisms (positive and negative) regulate physiological processes.

• Anatomical Landmarks: Specific points on the body used for reference in medical and anatomical studies.

Example: Homeostasis

Regulation of body temperature is an example of homeostasis. When body temperature rises, mechanisms such as sweating are activated to cool the body.

Additional info:

Negative feedback reduces the effect of the original stimulus (e.g., blood glucose regulation), while positive feedback amplifies it (e.g., childbirth contractions).

Chapter 2: Chemical Basis of Life

Key Terminology

• Covalent Bond, Water, Peptide Bond, Isotope, Coenzyme, Hydrogen Bond, Hydrophilic/Hydrophobic, Polar/Nonpolar, Monomer/Polymer, pH, Buffer: Terms related to chemical properties and interactions in biological systems.

Major Concepts

• Covalent vs. Ionic vs. Hydrogen Bonds: Covalent bonds involve sharing electrons, ionic bonds involve transfer of electrons, and hydrogen bonds are weak attractions between polar molecules.

• Importance of Ions and Electrolytes: Ions such as Na+, K+, and Cl- are essential for nerve impulses and muscle contraction. Electrolytes help maintain fluid balance.

• Acids, Bases, and pH: Acids release H+ ions, bases accept H+ ions. pH measures hydrogen ion concentration: $pH = -\log[H^+]$

• Buffers: Substances that minimize changes in pH, crucial for maintaining homeostasis.

• Functional Groups: Groups such as hydroxyl, carboxyl, amino, phosphate, and methyl determine the properties of organic molecules.

Example: Water as a Solvent

Water's polarity allows it to dissolve many substances, making it an excellent solvent for biological reactions.

Additional info:

Hydrophilic molecules interact well with water, while hydrophobic molecules do not.

Chapter 3: Cellular Structure and Function

Key Terminology

• Active Transport, RNA, DNA, Phagocytosis, Glycogenesis, Cell Membrane, Mitosis, Diffusion, Osmosis, Endocytosis, Exocytosis, Stem Cells, Receptor-Mediated Endocytosis: Terms describing cellular processes and structures.

Major Concepts

• Fluid Mosaic Model: The cell membrane consists of a phospholipid bilayer with embedded proteins, allowing selective transport and communication.

• Cytoplasm and Organelles: The cytoplasm contains organelles such as mitochondria (energy production), ribosomes (protein synthesis), and the nucleus (genetic material).

• DNA and RNA: DNA stores genetic information; RNA is involved in protein synthesis. DNA replication ensures genetic continuity.

• Transport Mechanisms: Includes diffusion (movement from high to low concentration), osmosis (water movement), active transport (energy-dependent movement), endocytosis (cellular intake), and exocytosis (cellular export).

• Concentration Gradients: Gradients drive passive transport; active transport moves substances against gradients using energy.

• Osmotic Pressure: The pressure required to prevent water movement across a membrane. Related to solute concentration.

• Solution Types: Isotonic (equal solute concentration), Hypotonic (lower solute concentration outside cell), Hypertonic (higher solute concentration outside cell).

Example: Osmosis

When a cell is placed in a hypotonic solution, water enters the cell, potentially causing it to swell and burst.

Additional info:

Stem cells are undifferentiated cells capable of giving rise to specialized cell types.

Table: Comparison of Solution Types

Solution Type	Solute Concentration (Outside Cell)	Effect on Cell
Isotonic	Equal to inside	No net water movement; cell remains unchanged
Hypotonic	Lower than inside	Water enters cell; cell may swell or burst
Hypertonic	Higher than inside	Water leaves cell; cell shrinks (crenation)

Additional info:

Osmolarity is calculated as: $\text{Osmolarity} = \frac{\text{Number of osmoles of solute}}{\text{Liter of solution}}$