Master Human Physiology Lab

This is a study guide for a Human Physiology Lab final exam. It covers various topics from different lab sessions.

Lab 1: Osmosis, Tonicity, and Mechanisms of Transport Across a Membrane

• Osmosis is defined as the movement of water across a membrane.
• Hyperosmotic, hyposmotic, and isosmotic solutions are different in terms of their osmolarity.
• Tonicity refers to how the extracellular fluid affects cell volume.
• Hypertonic, hypotonic, and isotonic solutions have different effects on cell shape and size.
• Active transport mechanisms require energy while passive transport mechanisms do not.
• Examples of active mechanisms include ion pumps, exocytosis, and endocytosis. Examples of passive transport mechanisms include diffusion and osmosis.

Lab 2: Internal and External Environment, Fluid Compartments, and Signal Pathways

• Internal environment refers to the inside of the body while external environment refers to things outside the body.
• The body has two fluid compartments: extracellular fluid (which has two compartments, interstitial fluid and plasma) and intracellular fluid.
• A typical signaling pathway consists of five steps, starting with an extracellular signaling molecule and ending with a response from the target protein.

Lab 3: Hypothalamic-Pituitary-Adrenal Cortex Pathway and Hypothalamic-Pituitary-Thyroid Pathway

• The hypothalamic-pituitary-adrenal cortex pathway is responsible for cortisol release in response to stress.
• The hypothalamic-pituitary-thyroid pathway is responsible for thyroid hormone release.
• Both pathways involve negative feedback mechanisms.
• Lab results for hyperthyroidism and hypothyroidism differ in terms of thyroid hormone and TSH levels.

Lab 4: Insulin and Glucagon

• Insulin and glucagon are hormones that regulate blood sugar levels.
• Insulin lowers blood sugar levels while glucagon increases them.
• Insulin levels are high during a fed state while glucagon levels are high during a fasted state.
• Type 1 diabetes is caused by the destruction of beta cells in the pancreas while type 2 diabetes is caused by insulin resistance.

Lab 5: Graded Potentials and Action Potentials

• Graded potentials are variable in strength and start mainly at the dendrites or soma.
• Action potentials are all the same strength and start at the trigger zone of the axon hillock.
• Sodium and calcium channels open to create an excitatory response while potassium channels open to create an inhibitory response.

Lab 6: Neuromuscular Junction

• The neuromuscular junction involves the synaptic knob, synaptic cleft, and motor end plate.
• Sodium and calcium voltage-gated channels open in the synaptic knob, triggering the release of acetylcholine.
• Chemically gated acetylcholine receptors and nonspecific monovalent cation channels open in the motor end plate, leading to depolarization and the creation of an end plate potential.

Lab 9: Heart and Blood Flow

• Blood flows through the heart and body in a specific pathway involving various vessels and valves.
• EDV, ESV, stroke volume, and cardiac output are all important measures of heart function.
• Left-sided and right-sided heart failure can affect pulmonary and systemic blood pressures differently.

Lab 10: Hydrostatic Pressure and Col3. How does severe malnutrition affect capillary osmotic pressure?

• Severe malnutrition would cause a decrease in capillary osmotic pressure due to a decrease in plasma proteins, particularly albumin. • Albumin is the most abundant plasma protein. • Malnutrition or a protein-poor diet would deplete albumin stores because they would be used to make proteins that are not being consumed in the diet.

4. What would happen to capillary absorption if plasma proteins leaked out of the capillary?

• If plasma proteins leaked out of the capillary, it would reduce the absorption of fluids from the capillary to the surrounding tissues. • This would also result in edema forming as fluid would gather in the interstitial spaces between cells.

Lab 11

1. Know the formula for pulmonary and alveolar ventilation rates.

• Pulmonary Ventilation = tidal volume x respiratory rate • Alveolar ventilation = ventilation rate x (tidal volume – dead air space) • Dead air space = 150 mL

2. Know how the partial pressure of oxygen is affected by:

a. Hyperventilation

• Oxygen levels increase because you are taking deeper breaths and bringing more air into the body.

b. Hypoventilation

• Oxygen levels decrease because you are taking shallower breaths, and not enough oxygen is coming into the body.

3. Know how the partial pressure of carbon dioxide is affected by:

a. Hyperventilation

• Carbon dioxide levels are decreased because excessive breathing is expelling more CO2 from the body than normal.

b. Hypoventilation

• Carbon dioxide levels are increased because the body is producing more CO2 than it can eliminate because you aren't able to take deeper breaths to get more oxygen into the body.

4. What is the best and easiest way to treat hyperventilation?

• The best and easiest way to treat hyperventilation is to use a paper bag to replace the CO2 levels in the body.

5. What is the difference between fetal and maternal hemoglobin when it comes to their affinities to oxygen?

• Fetal hemoglobin has a higher affinity for oxygen to ensure oxygen gets transferred from the maternal blood to the fetal blood in the placenta.
• Maternal hemoglobin releases more oxygen to the placenta for the fetus.

Lab 12

1. Be able to trace a drop of water from the glomerulus to the urethra.

• Plasma in the afferent arteriole • Glomerulus • Bowman's capsule • Proximal convoluted tubule • Descending limb of the loop of Henle • Loop of Henle • Ascending limb of the loop of Henle • Distal convoluted tubule • Collecting duct • Renal papilla • Renal calyces • Renal pelvis • Ureter • Bladder • Urethra

2. How does a diuretic treat edema? Be detailed.

• A diuretic treats edema by helping rid the body of excess water through the urine.
• It creates a decrease in the hydrostatic pressure in the capillaries so filtration will decrease.
• This will increase absorption of water and pull it back into the tissues.

3. Know the hydrogen concentration level and pH of the following:

a. Metabolic acidosis