Lab Exam Flashcards
What happens to the mass of annelid worms as seawater concentration increases?
Mass of worm decreases.
What is the osmolality of 100% seawater?
1000 mOsm.
In Experiment 2 on animal cells, what happens to cells in a hypotonic solution?
Cells grow as water enters cells.
What occurs to cells in a hypertonic solution?
Cells shrink as water exits cells.
What is lysis in the context of osmosis?
Cell undergoes rupture due to too much water entering.
What is crenation?
Shrinking of red blood cells due to water loss in a hypertonic solution.
What does the standard error of the mean represent?
Variability within class data.
Define tidal volume (TV).
Volume of air entering/leaving lungs during a single breath (resting ~0.5 ml).
What is functional residual capacity (FRC)?
Volume of air in the lungs at the end of a normal passive expiration (~2.2 L).
What is the maximum volume of air that can be moved out during a single breath called?
Vital Capacity (VC).
What is inspiratory capacity (IC)?
Maximum volume of air a person can inhale after a normal exhale.
What happens to tidal volume after exercise?
Tidal volume increases.
What is the purpose of a spirometer?
Measures lung function, including how much air you inhale and exhale.
What does the P wave in an ECG represent?
SA node begins depolarization of the atrium.
What does the QRS complex indicate?
Ventricular depolarization
What role does the sympathetic nervous system play during exercise?
Increases heart rate and redirects blood to working muscles.
What is bradycardia?
An abnormally slow heart rate, typically below 60 beats per minute.
What does the respiratory quotient indicate?
Based on the diet of an organism, it reflects the type of substrates used for metabolism.
What is the difference between standard metabolic rate (SMR) and basal metabolic rate (BMR)?
SMR is for ectotherms and BMR is for endotherms.
What is metabolic rate?
The rate at which energy is used by an organism.
What is osmoregulation?
active regulation of the osmotic pressure (concentration of solutes) of an organism’s body fluids,
metanephridia
a type of excretory organ found in some invertebrates invertebrates that filters body fluid and excretes waste through an external pore
What physiological adaptations allow animals at high altitudes to maintain aerobic performance?
Higher RBC count, greater lung ventilation, and larger lung size.
What is indirect calorimetry?
A method to estimate metabolic rate by measuring gas exchange.
What is the role of the phospholipid bilayer in animal cells?
It is semi-permeable, allowing small, uncharged molecules like water to pass through.
The phospholipid bilayer is essential for maintaining the cell’s internal environment and facilitating osmosis.
What is the main organ responsible for osmoregulation in vertebrates?
Kidneys.
The kidneys filter blood, reabsorb water and solutes, and excrete waste.
How do kidneys adjust urine concentration?
To regulate blood osmolality, volume, and electrolyte balance.
This process is crucial for maintaining homeostasis.
Which organ in fish regulates ion exchange with water?
Gills.
Gills play a vital role in osmoregulation in aquatic environments.
What role do skin and salt glands play in osmoregulation?
They excrete excess salts in some reptiles and birds.
This is important for maintaining salt balance in terrestrial environments.
Which hormones regulate osmoregulation?
ADH (antidiuretic hormone) is regulated by the hypothalamus and pituitary gland.
ADH helps control water retention in the body.
What physiological changes occur in the respiratory system during exercise?
Increased breathing rate and depth
increased ventilation rate
increased cardiac output
These changes ensure adequate oxygen supply to meet metabolic demands.
How do lung capacities differ between men and women?
Men typically have larger lungs and greater lung capacities due to larger thoracic size and muscle mass.
Women may have slightly more efficient breathing patterns despite lower lung volumes.
What is CO₂ a byproduct of?
Aerobic cellular respiration, specifically in the Krebs cycle inside mitochondria.
CO₂ production is essential for energy metabolism in cells.
In what forms is CO₂ transported in the blood?
- As bicarbonate (HCO₃⁻) (major form)
- Bound to hemoglobin
- Dissolved in plasma
These forms facilitate CO₂ transport from tissues to the lungs.
What happens to pulse amplitude during heat exposure?
It increases during heat (vasodilation) and goes back to normal during cooldown (vasoconstriction).
This is part of the body’s thermoregulatory response.
What occurs to pulse amplitude during cool conditions?
It decreases during cool (vasoconstriction) and goes back to normal during the rewarm phase (vasodilation).
This response helps maintain body temperature.
What effect does gravity have on pulse amplitude?
Pulse amplitude decreases during elevation and increases when lowered.
This reflects changes in blood flow and pressure due to gravity.
What is the function of aquaporins?
Aquaporins allow for water transport and selective permeability of water into cells.
Where in the human body are aquaporins found?
Aquaporins are found within the plasma membrane of cells in the kidneys, digestive system, exocrine glands, and more.
Why is it a bad idea for humans to drink sea water?
Drinking sea water may cause dehydration and forces kidneys to work harder due to high sodium chloride content.
What osmoregulatory challenges do marine animals face?
Marine animals risk losing water and gaining too much salt due to the hypertonic nature of ocean water.
How do marine animals cope with osmoregulatory challenges?
They have specialized systems such as gills or kidneys that help excrete excess salt from drinking seawater.
What osmoregulatory challenges do freshwater animals face?
Freshwater animals face water moving into their bodies and salts leaking out due to the hypotonic environment.
How do freshwater animals cope with osmoregulatory challenges?
They produce large amounts of urine and actively absorb salt through skin or gills.
What osmoregulatory challenges do terrestrial animals face?
Terrestrial animals risk losing water to the environment due to evaporation, breathing, sweat, and waste.
How do terrestrial animals cope with osmoregulatory challenges?
They drink water and produce concentrated urine and dry feces to conserve water.
Why is diffusion an inefficient respiratory strategy for thick organisms?
Cells deep inside thicker organisms are too far from the surface for oxygen to reach them by diffusion.
What happens to the surface area to volume ratio as body size increases?
As body size increases, the surface area to volume ratio decreases, leading to less surface area for gas exchange.
What adaptations do animals at higher altitudes have for low oxygen levels?
They have a higher RBC count, greater lung ventilation, and larger lung size.
How does smoking damage the alveoli in the lungs?
Smoking breaks down the walls of the alveoli, reducing the surface area available for gas exchange.
What spirometry differences would you expect between smokers and non-smokers?
Smokers would show decreased vital capacity and reserve volumes.
What is the electrical conduction pathway that initiates a heart contraction cycle?
SA Node, AV Node, Bundle of His, Purkinje Fibers.
How does the sympathetic nervous system affect heart rate?
The sympathetic nervous system increases heart rate by releasing norepinephrine.
How does the parasympathetic nervous system affect heart rate?
The parasympathetic nervous system decreases heart rate by releasing acetylcholine.
What is the baroreceptor reflex?
A negative feedback loop that detects changes in blood pressure and triggers automatic responses to normalize it.
What happens when blood pressure rises in the baroreceptor reflex?
Baroreceptors stretch more, send faster signals, release acetylcholine, slow heart rate, and dilate blood vessels.
What happens when blood pressure falls in the baroreceptor reflex?
Baroreceptors stretch less, send slower signals, increasing sympathetic activity to raise heart rate and constrict blood vessels.
What is the diving reflex?
A physiological response that optimizes oxygen conservation during submersion in water.
How does the diving reflex help during cold water submersion?
Heart rate decreases (bradycardia) to conserve oxygen, and vasoconstriction redirects blood flow to vital organs.
What is the difference between SMR/BMR and MMR?
SMR is the minimum metabolic rate at rest for ectotherms; BMR is for endotherms; MMR is the highest metabolic rate during peak activity.
What is aerobic scope?
Aerobic scope is the difference between MMR and BMR/SMR, indicating the highest capacity for aerobic activity beyond maintenance needs.
Why does the aerobic scope of ectothermic animals decline as temperature rises?
As temperature rises, SMR increases and MMR decreases, leading to a reduced aerobic scope.
Why can many endotherms also be characterized as heterotherms?
Endotherms may allow body temperature to fluctuate under certain conditions, thus acting as heterotherms.
What is temporal heterothermy?
Temporal heterothermy is when body temperature varies over time.
What is regional heterothermy?
Regional heterothermy is when body temperature varies in different body parts simultaneously.
What is a benefit of temporal heterothermy?
Energy conservation by lowering metabolic rate during torpor or hibernation reduces food and oxygen needs.
What is a benefit of regional heterothermy?
Beneficial for heat retention in vital organs and muscles.
Formula for Inspiratory Capacity
IC = TV + IRV
Formula for expiratory capacity
EC = TV + ERV
Formula for Functional Residual Capacity
FRC = ERV + RV
Formula for Total Lung Capacity
TLC = TV + RV + IRV + ERV
