Comprehensive Study Guide for ANP Physiology Final Exam

Chapter 3: Cells and Tissues

Compare and contrast 5 types of epithelia?

Epithelial tissues serve various functions in the body, including protection, absorption, secretion, and exchange. Understanding their categories is essential for recognizing their roles in physiology.

• Exchange Epithelium: Allows rapid movement of substances; found in capillaries and lungs.

• Transporting Epithelium: Regulates the movement of substances; found in the intestines and kidneys.

• Ciliated Epithelium: Moves particles across surfaces; found in the respiratory tract.

• Protective Epithelium: Provides a barrier against mechanical stress; found in the skin and mouth.

• Secretory Epithelium: Produces and releases substances; found in glands.

Example: The lining of the small intestine is transporting epithelium, facilitating nutrient absorption.

(Video)

• Epithelial tissue covers body surfaces/organs, lines internal cavities/ducts, and makes glands.

• Sheets of tightly packed cells on a boundary adjacent to open space.

• Contains skin, lining of airways, salivory glands and tubes.

Compare and contrast types of connective tissue?

Connective tissues provide structural support, protection, and transport within the body. They are classified based on their composition and function.

• Loose Connective Tissue: Few fibers, Flexible, supports organs; e.g., adipose tissue.

• Dense Connective Tissue: Tightly packed collagen fibers, Strong, resists tension; e.g., tendons and ligaments.

• Cartilage: Chondrocytes, Cushions joints, flexible support e.g. ear

• Bone: Osteocytes, Rigid support, stores minerals.

• Blood: Fluid tissue that transports nutrients and gases.

Example: Bone tissue provides structural support and is a reservoir for calcium.

Compare and contrast 4 tissue types?

The body is composed of four primary tissue types, each with distinct functions.

Tissue Type	Main Function	Location
Epithelial	Protection, absorption, secretion	Skin, lining of organs
Connective	Support, transport, storage	Bone, blood, cartilage
Muscle	Movement	Skeletal muscles, heart
Nervous	Communication, control	Brain, nerves

Chapter 4: Energy and Cellular Metabolism

ATP Production: Cellular Respiration Overview

ATP is the primary energy currency of the cell, produced through cellular respiration. The process involves several steps, each occurring in specific cellular locations and yielding distinct products.

• Glycolysis: Occurs in cytoplasm; converts glucose to pyruvate; yields 2 ATP and 2 NADH.

Glucose is split in half, energy is captured as ATP and NADH

• Pyruvate Oxidation: Occurs in mitochondria; converts pyruvate to acetyl-CoA; yields NADH.

Each pyruvate loses a carbon (as CO2), forming acetyl-CoA and more NADH

• Krebs Cycle (Citric Acid Cycle): Occurs in mitochondrial matrix; yields 2 ATP, 6 NADH, 2 FADH2 per glucose.

All remaining carbons from glucose are released as CO2; lots of electron carriers (NADH and FADH2) are made.

• Electron Transport Chain: Occurs in mitochondrial inner membrane; uses NADH and FADH2 to produce ~28 ATP.

Elecrron carriers drop off electrons, powering ATP synthesis; O2 is the final electron acceptor, forming water.

Equation:

$\text{C}_6\text{H}_{12}\text{O}_6 + 6\text{O}_2 \rightarrow 6\text{CO}_2 + 6\text{H}_2\text{O} + \text{ATP}$

Example: Glucose metabolism yields a total of about 30-32 ATP per molecule.

Chapter 5: Membrane Dynamics

Intracellular Fluid (ICF) vs. Extracellular Fluid (ECF)

Body fluids are divided into intracellular and extracellular compartments, each with distinct compositions and functions.

• ICF: Fluid inside cells; high in K+, low in Na+.

• ECF: Fluid outside cells; high in Na+, low in K+.

Example: ECF includes plasma and interstitial fluid.

Transport Across Membranes

Cells regulate the movement of substances across membranes via various mechanisms.

• Simple Diffusion: Movement down a concentration gradient; no energy required.

• Facilitated Diffusion: Uses carrier proteins; no energy required.

• Active Transport: Moves substances against a gradient; requires ATP.

• Osmosis: Movement of water across a membrane.

(Video)

Intro to membrane transport: they are semi-permeable and can act as barriers to prevent diffusion of molecules.

Some molecules can freely diffuse across a membrane without facilitation from a protein.

can freely diffuse = small, uncharged, nonpolar/hydrophobic (no problems crossing membrane)

cannot freely diffuse = large, charged (+/-), polar/hydrophilic (molecules that cannot freely diffuse through membrane)

Membrane Potential: Depolarization, Repolarization, Hyperpolarization

Membrane potential changes are crucial for cell signaling.

• Depolarization: Membrane potential becomes less negative.

• Repolarization: Membrane potential returns to resting value.

• Hyperpolarization: Membrane potential becomes more negative than resting.

Graph: Membrane potential changes are visualized in action potential graphs.

Chapter 6: Communication, Integration, and Homeostasis

Compare and contrast neural vs endocrine reflexes?

Neural and endocrine reflexes are mechanisms for maintaining homeostasis, differing in speed and specificity.

Feature	Neural Reflex ex: knee-jerk reflex	Endocrine Reflex ex: regulation of blood glucose by insulin
Speed	Fast (milliseconds)	Slow
Specificity	High	Low
Signal Type	Electrical (AP) /Chemical Neurotransmitters	Chemical (hormones in blood)
Duration	Short-lived effectors	Long-lasting effects

4 Categories of Membrane Receptors?

Membrane receptors mediate cellular responses to external signals.

• Receptor-channel: When a ligand binds, the channel opens/closes, allowing specific ions to flow across the membrane.

• Receptor-enzyme: - Linked to G Proteins - ligand binding activates the G-protein, which triggers various intracellular signaling pathways

• G protein-coupled receptor: -Receptors have an enzyme (often kinase) - ligand binding enzymes activates the enzyme, which catalyzes a reaction

• Integrin receptor: -linked to cytoskeleton - ligand binding changes shape of receptor, affecting cell structure

Chapter 7: Introduction to the Endocrine System

Hormones Overview

Hormones are chemical messengers secreted by endocrine glands, regulating various physiological processes.

• Peptide/Protein Hormones: Made from amino acids (e.g., insulin, growth hormone). Usually water-soluble and act on cell surface receptors.

• Steroid Hormones: Derived from cholesterol (e.g., cortisol, estrogen, testosterone). Lipid-soluble and act on intracellular receptors.

• Amino Acid-Derived Hormones: Made from single amino acids (e.g., thyroid hormones, epinephrine).

  How do hormones work?

• Secreted into the blood by endocrine cells/glands.

• Travel to distant target tissues.

• Bind to specific receptors (on the cell membrane or inside the cell).

• Trigger specific responses (e.g., growth, metabolism, stress response)

Chapter 8: Neurons: Cellular and Network Properties

Action Potential

Action potentials are rapid changes in membrane potential that propagate along neurons.

• Resting State: The neuron is at rest, with a negative membrane potential (about -70 mV). - Na⁺ and K⁺ channels are closed.

• Depolarization: A stimulus causes Na⁺ channels to open. - Na⁺ rushes into the cell, making the inside more positive. - Membrane potential rises rapidly toward +30 mV.

• Repolarization: Na⁺ channels close, K⁺ channels open. - K⁺ leaves the cell, restoring the negative membrane potential.

• Hyperpolarization: K⁺ channels stay open a bit longer, causing the membrane potential to dip below the resting level. - Eventually, the membrane returns to its resting state.

(Video)

• Action potentials are all-or-none events—once triggered, they always reach full amplitude.

• They allow neurons to communicate quickly and efficiently.

• Depolarization, repolarization, and hyperpolarization are the main phases.

Chapter 9: The Central Nervous System

Cranial Nerves

Cranial nerves are twelve pairs of nerves that emerge directly from the brain, each with specific functions.

Number	Name	Function
I	Olfactory	Smell
II	Optic	Vision
III	Oculomotor	Eye movement
IV	Trochlear	Eye movement
V	Trigeminal	Sensory/motor face
VI	Abducens	Eye movement
VII	Facial	Facial expression
VIII	Vestibulocochlear	Hearing/balance
IX	Glossopharyngeal	Taste/swallowing
X	Vagus	Autonomic control
XI	Accessory	Neck muscles
XII	Hypoglossal	Tongue movement

Chapter 12: Muscles

Steps of Muscle Contraction

Muscle contraction involves a sequence of events known as excitation-contraction coupling.

1. Action potential arrives at the neuromuscular junction.

2. Acetylcholine released and binds to receptors.

3. Depolarization of the muscle membrane.

4. Calcium is released from the sarcoplasmic reticulum.

5. Calcium binds to troponin, moves tropomyosin.

6. Myosin binds to actin, power stroke occurs.

7. ATP binds to myosin, causing detachment from actin.

8. The cycle repeats as long as calcium and ATP are present.

Comparison of Muscle Types

Feature	Skeletal	Cardiac	Smooth
Control	Voluntary	Involuntary	Involuntary
Striations	Yes	Yes	No
Nucleus	Multinucleated	Single	Single
Location	Attached to bones	Heart	Walls of organs

Chapter 14: Cardiovascular Physiology

Action Potential of Cardiac Contractile Cell

Cardiac contractile cells have unique action potentials, crucial for heart function.

• Phase 0: Rapid depolarization (Na+ influx).

• Phase 1: Initial repolarization (K+ out).

• Phase 2: Plateau (Ca2+ influx balances K+ out).

• Phase 3: Repolarization (K+ out).

• Phase 4: Resting potential.

Key Points:

• The plateau phase is unique to cardiac contractile cells and prevents rapid, repeated contractions (tetany).

• This ensures the heart has time to fill and pump efficiently.

• Action potentials in cardiac cells are longer than those in neurons or skeletal muscle.Equation:

$\text{AP}_{\text{cardiac}} = \text{Phase 0} \rightarrow \text{Phase 1} \rightarrow \text{Phase 2} \rightarrow \text{Phase 3} \rightarrow \text{Phase 4}$

Chapter 17: Mechanics of Breathing

Lung Volumes and Capacities

Lung volumes and capacities are measurements used to assess respiratory function.

• Tidal Volume (TV): Air inhaled/exhaled in one breath (~500 mL).

• Inspiratory Reserve Volume (IRV): Extra air inhaled after normal inspiration.

• Expiratory Reserve Volume (ERV): Extra air exhaled after normal expiration.

• Residual Volume (RV): Air remaining after maximal exhalation.

• Inspiratory Capacity (IC): IC= TV + IRV.

• Functional Residual Capacity (FRC)= ERV + RV.

• Vital Capacity (VC): VC= TV + IRV + ERV.

• Total Lung Capacity (TLC)= TV+IRV+ERV+RV

Equation:

$\text{VC} = \text{TV} + \text{IRV} + \text{ERV}$

$\text{TLC} = \text{VC} + \text{RV}$

Chapter 19: The Kidneys

Order of Structures for Filtrate in the Nephron

Filtrate passes through several structures in the nephron during urine formation.

1. Glomerulus

2. Bowman's capsule

3. Proximal tubule

4. Loop of Henle (descending, then ascending limb)

5. Distal tubule

6. Collecting duct

Order of Vascular Structures in the Nephron

1. Afferent arteriole

2. Glomerulus

3. Efferent arteriole

4. Peritubular capillaries

5. Vasa recta

Volume/% of Fluid at Nephron Points

Location	Volume (% of original)
Bowman's capsule	100%
End of proximal tubule	~30%
End of loop of Henle	~15%
End of collecting duct	~1%

Additional info: Values are approximate and may vary based on hydration and hormonal regulation.

Glomerular Filtration Rate (GFR) Determinants

GFR is determined by filtration pressure, surface area, and permeability of the glomerular membrane.

What Determines GFR? (Fig 19.6)

• Glomerular Filtration Rate (GFR) is determined by:

  • Net filtration pressure (NFP)

  • Filtration coefficient (surface area and permeability of glomerular capillaries)

• GFR = Filtration coefficient × Net filtration pressure

• Three main pressures determine filtration at the glomerulus:

  1. Glomerular hydrostatic pressure (PGC): Blood pressure in glomerular capillaries (favors filtration).

  2. Colloid osmotic pressure (πGC): Due to plasma proteins in glomerular capillaries (opposes filtration).

  3. Capsular hydrostatic pressure (PBC): Fluid pressure in Bowman’s capsule (opposes filtration).

• Net filtration pressure = PGC - πGC - PBC

Chapter 21: The Digestive System

Pathway of Food Through the GI Tract

Food travels through the digestive system in a specific order.

1. Mouth

2. Pharynx

3. Esophagus

4. Stomach

5. Small intestine (duodenum, jejunum, ileum)

6. Large intestine (cecum, colon, rectum)

7. Anus

GI Hormones

Hormone	Source	Function
Gastrin	Stomach	Stimulates acid secretion
Secretin	Small intestine	Stimulates bicarbonate secretion
Cholecystokinin (CCK)	Small intestine	Stimulates bile and enzyme release
GIP Gastric Inhibitory Peptide	Small intestine	Stimulates insulin release

Summary: GI hormones coordinate digestion by controlling enzyme secretion, acid production, motility, and absorption. Each hormone is released in response to specific nutrients or conditions in the GI tract.

Overview of Function (Fig 21.6)

The digestive system’s main functions are: ingestion, mechanical breakdown, digestion (chemical breakdown), absorption of nutrients, and elimination of wastes. Each region of the GI tract is specialized for one or more of these steps, working together to process food and extract energy and nutrients.

Secretory Cells of Gastric Mucosa (Fig 21.9A)

• Mucous cells: Secrete mucus to protect the stomach lining from acid and enzymes.

• Parietal cells: Secrete hydrochloric acid (HCl) and intrinsic factor (for vitamin B12 absorption).

• Chief cells: Secrete pepsinogen (inactive enzyme, converted to pepsin by HCl).

• Enteroendocrine (G) cells: Secrete gastrin, a hormone that stimulates acid secretion.

Key Takeaway: The digestive system breaks down food and absorbs nutrients, while the stomach’s secretory cells each play a specific role in digestion and protection.