PHYS 288: Exam 1

Most aquatic animals, including most bony fishes.

A connective tissue consisting of several cell types suspended in plasma.

Body size and habitat.

1. By drinking 2) By eating 3) By absorbing it via osmosis 4) As a by-product of cellular respiration.

In the proximal tubule.

To minimize blood loss from ruptured blood vessels by assisting in the formation of clots.

They are part of the immune system and fight infections.

It pumps Na+ out of the cell and K+ into the cell, creating an electrochemical gradient.

They use energy released by moving another substance against the gradient to transport ions.

It leads to the release of antiduretic hormone (ADH), promoting water reabsorption.

The relative thickness of the medulla.

In the renal corpuscle.

Alveoli.

It maintains an osmotic gradient.

It drives the osmolarity gradient in the medulla.

Water moves out following the osmolarity gradient in the medulla.

The process of maintaining water balance.

A method of underwater diving that does not require a breathing apparatus; divers hold their breath.

Osmoregulators maintain a tissue osmolarity different from the environment, while osmoconformers maintain a similar osmolarity.

The process of maintaining ion balance.

Pressure changes, cardiovascular challenges, N2 narcosis, and oxygen limitations.

By increasing total body oxygen storage or increasing metabolic demand.

Movement of one ion is powered by diffusion, with at least one ion moving from high to low concentration.

Always 10% greater amount of oxygen.

A flow pattern where two fluids move in the same direction, making gas exchange difficult.

Trachea, Lung, Bronchi, Bronchioles, and Alveoli.

Fick’s Law states that diffusion rate is proportional to the diffusion constant, area for gas exchange, and the difference in partial pressure, divided by the distance.

A long Loop of Henle and a stronger osmolarity gradient.

They tend to have increased values except for lung size.

Gains and losses of water.

Movement along an electrochemical gradient without energy use, including direct diffusion and facilitated diffusion.

Movement against an electrochemical gradient that uses energy (ATP).

To transport oxygen from the lungs to tissues and carbon dioxide from tissues to lungs.

99.9%.

From areas of low osmolarity to areas of high osmolarity.

Alternative strategies beyond skin respiration.

Up to 4 molecules.

Pro: expands the environmental space for organisms; Con: energetically expensive.

Pro: energetically cheap; Con: highly dependent on external environmental conditions.

By the nervous system.

Receptors in the carotid body sample blood pH, and the brainstem integrates this information to adjust breathing via the diaphragm.

It results in a large difference in the amount of O2 delivered to resting versus exercising tissues.

By blowing out very concentrated amounts of salt.

Bidirectional is like tidal breathing; unidirectional is like a race track.

Mammals, most amphibians, sharks, and some bony fishes.

Uric acid.

Aldosterone.

They have a heart to pump hemolymph but limited piping.

Blood volume, hematocrit, hemoglobin concentration [Hb], and hemoglobin O2 affinity.

1. Urine and feces 2) Evaporation 3) Osmotic loss.

Flexible chest walls that allow for collapse.

A physiological response that includes apnea, bradycardia, and regional vasoconstriction.

The absence of breathing.

Aldosterone.

Because it is effective only in wet environments.

About 100 mm Hg.

It suppresses ADH secretion from the pituitary.

By drinking.

Primarily through their gills.

When water and blood flow in opposite directions to maximize oxygen transfer.

Pacific Salmon.

To reabsorb water and solutes, while urea does not exit.

Highly permeable to water but impermeable to solutes.

Na+ and Cl-.

Active transport in the upper part of the ascending limb.

They are leaky to liquids and small molecules like glucose, proteins, and hormones.

Used for gas exchange.

They circulate water through themselves.

Blood pressure goes down.

Blood returns to the left atrium from the lungs, enters the left ventricle, and is pumped to the body.

For water conservation and selective removal of salts.

They increase red blood cell counts.

36 ATP.

Myoglobin O2 affinity.

Fluid and small solutes are pushed through pores into Bowman’s capsule, while large molecules and cells remain in the bloodstream.

Aerobic respiration.

The maximum breath-hold possible without an increase in blood lactate concentration during or after the dive.

It requires more time at the surface to recover.

1. Convert to pyruvate for aerobic metabolism (requires O2). 2. Convert to pyruvate and back to glucose for storage (requires ATP).

Maintaining a stable internal environment in the face of internal and external challenges.

Through conformity, which means their internal environment approaches external conditions.

Through their gills.

Projections of the respiratory surface that work in water.

The partial pressure of oxygen in the tissue.

The affinity for O2 decreases as pH decreases.

They are converted to bicarbonate (HCO3^-) and hydrogen ions (H+) using the enzyme carbonic anhydrase.

A key ion cotransporter.

Right above the nostrils/air ducts.

Lungs expand and contract in response to pressure changes in the chest cavity.

The solubility of gas and temperature.

Water moves out following the osmolarity gradient in the medulla.

The hydration status of the individual.

Approximately 65%.

Thermoregulation, osmoregulation, and ion regulation.

Blood enters the right atrium, moves to the right ventricle, and is pumped to the lungs.

The left ventricle.

High pressure, low volume, stretchy large vessels, and smaller arteries use smooth muscle to control blood flow.

Aerobic and anaerobic.

The mammalian dive reflex, which redirects blood to vital organs and slows the heart rate.

Enzymes have an optimal range of values over which they perform best.

To allow solutes and water to pass out of the blood into the nephron.

They clump together and become ineffective.

It restricts blood flow to the limbs to conserve oxygen.

O2 is the final electron acceptor in the electron transport chain.

Ventilation → Diffusion at respiratory surface → Circulation → Diffusion at tissues → Cellular respiration.

Air contains a constant 21% O2, while water generally has much less O2.

Proteins → Amino acids → NH2 (Amino groups) → Ammonia → Urea → Uric acid.

Due to one-way air flow, which affects partial pressures.

Large amounts of oxygen and fuel, and remove waste.

Ammonia requires more water than urea.

Valves.

Nocturnal activity and dietary shifts to consume water-rich insects.

By concentrating their urine and reducing water loss from evaporation.

They have Hb with high O2 affinity (low P50).

Increased red blood cell counts.

It shifts to the right, unloading more oxygen into the tissues.

Leads to the reabsorption of water.

They have a heart and vessels to control blood flow.

Due to the relatively large surface area of their lungs.

The SA node.

One RBC in diameter and one cell layer thick.

A unidirectional respiratory system with countercurrent gas exchange.

They have large hearts relative to body size, supporting larger cardiac output.

Hyperventilation (increased breathing rate).

They alter molecules that interact with hemoglobin to lower its affinity for oxygen.