Bio 116 Exam 5 Questions with
Complete Answers
sympathetic vs. parasympathetic nervous system - ANSWER-The sympathetic
nervous system activates the fight or flight response during a threat or perceived
danger, and the parasympathetic nervous system restores the body to a state of
calm
Regulator - ANSWER-internal mechanisms to maintain internal setpoints despite
external changes (animals whose temp is always at setpoint)
Conformer - ANSWER-internal conditions can vary with environmental changes
(animals whose temp can change based on environmental change)
How do trees survive freezing temperatures? - ANSWER-- Increases fluidity of
membranes
- Add sugars to xylem & phloem - act as antifreeze
Heat Exchange - ANSWER-1. radiation
2. evaporation (panting, sweating)
3. convection (warm air goes up, cold air goes down)
4. conduction (surfaces)
countercurrent exchange - ANSWER-the opposite flow of adjacent fluids that
maximizes transfer rates; for example, blood in the gills flows in the opposite
direction in which water passes over the gills, maximizing oxygen uptake and carbon
dioxide loss.
What are the appropriate steps to address this response? - ANSWER-Change →
sensor → integrator → effector → response
thermoregulation - ANSWER-
positive feedback - ANSWER-Feedback that tends to magnify a process or increase
its output.
negative feedback - ANSWER-
Feedback Mechanisms work at: molecular level - ANSWER-transcription/translation
Feedback Mechanisms work at: cellular level - ANSWER-turn metabolic pathways
on & off
, Feedback Mechanisms work at: organ level - ANSWER-respond to internal &
external stimuli
Excretory System - ANSWER-- Kidneys - filtration
- Regulates water & solute (electrolyte) balance
- Relative concentrations of water & ions must be maintained in specific range
Osmoregulation - ANSWER-mechanisms to control solute concentrations by taking
in and letting out water
Movement of molecules across membrane depends on... - ANSWER-size, charge,
hydrophobicity, etc
water moves through... - ANSWER-aquaporins
Osmoregulation in marine fish - ANSWER-1) Marine fish are hypoosmotic to their
environment, leading to dehydration
2) Uptake water through food and and seawater
3) Discharge salt through gills and through concentrated urine
osmoregulation in freshwater fish - ANSWER-1) Freshwater fish are hyperosmotic to
their environment, leading to water gain (too little salt)
2) Uptake salt through gills and in food
3) Discharge water through dilute urine
Nitrogenous Waste - ANSWER-- All animals need to secrete nitrogenous wastes due
to their toxicity
- Ammonia is basic → causes pH change
- Ammonia → urea → uric acid (most toxic to least toxic; cheapest to most
expensive)
Why is ammonia toxic? - ANSWER-- The reaction of glutamate dehydrogenase is
favored towards use of alpha-ketoglutarate to make glutamate
- The TCA cycle shuts down due to a lack of alpha-ketoglutarate
(nothing to do with pH!)
α-ketoglutarate - ANSWER-a critical product of the TCA cycle in the mitochondria
protonephridia (flatworms) - ANSWER-an excretory system, such as the flame bulb
system of flatworms, consisting of a network of tubules lacking internal openings
insect digestive tract - ANSWER-malpighian tubules extend into hemolymph
mammalian kidney structure - ANSWER-
nephron structure - ANSWER-1. Blood enters glomerulus (Filtering process)
2. Filtrate enters Bowman's Capsule (Filtering process)
3. Proximal convoluted tubule (Reabsorption NaCl, nutrients, and water)
4. Loop of Henle (countercurrent exchange) (Down: water leaves via aquaporins
Up: reabsorbing salts, water stays because there are no aquaporins)
Complete Answers
sympathetic vs. parasympathetic nervous system - ANSWER-The sympathetic
nervous system activates the fight or flight response during a threat or perceived
danger, and the parasympathetic nervous system restores the body to a state of
calm
Regulator - ANSWER-internal mechanisms to maintain internal setpoints despite
external changes (animals whose temp is always at setpoint)
Conformer - ANSWER-internal conditions can vary with environmental changes
(animals whose temp can change based on environmental change)
How do trees survive freezing temperatures? - ANSWER-- Increases fluidity of
membranes
- Add sugars to xylem & phloem - act as antifreeze
Heat Exchange - ANSWER-1. radiation
2. evaporation (panting, sweating)
3. convection (warm air goes up, cold air goes down)
4. conduction (surfaces)
countercurrent exchange - ANSWER-the opposite flow of adjacent fluids that
maximizes transfer rates; for example, blood in the gills flows in the opposite
direction in which water passes over the gills, maximizing oxygen uptake and carbon
dioxide loss.
What are the appropriate steps to address this response? - ANSWER-Change →
sensor → integrator → effector → response
thermoregulation - ANSWER-
positive feedback - ANSWER-Feedback that tends to magnify a process or increase
its output.
negative feedback - ANSWER-
Feedback Mechanisms work at: molecular level - ANSWER-transcription/translation
Feedback Mechanisms work at: cellular level - ANSWER-turn metabolic pathways
on & off
, Feedback Mechanisms work at: organ level - ANSWER-respond to internal &
external stimuli
Excretory System - ANSWER-- Kidneys - filtration
- Regulates water & solute (electrolyte) balance
- Relative concentrations of water & ions must be maintained in specific range
Osmoregulation - ANSWER-mechanisms to control solute concentrations by taking
in and letting out water
Movement of molecules across membrane depends on... - ANSWER-size, charge,
hydrophobicity, etc
water moves through... - ANSWER-aquaporins
Osmoregulation in marine fish - ANSWER-1) Marine fish are hypoosmotic to their
environment, leading to dehydration
2) Uptake water through food and and seawater
3) Discharge salt through gills and through concentrated urine
osmoregulation in freshwater fish - ANSWER-1) Freshwater fish are hyperosmotic to
their environment, leading to water gain (too little salt)
2) Uptake salt through gills and in food
3) Discharge water through dilute urine
Nitrogenous Waste - ANSWER-- All animals need to secrete nitrogenous wastes due
to their toxicity
- Ammonia is basic → causes pH change
- Ammonia → urea → uric acid (most toxic to least toxic; cheapest to most
expensive)
Why is ammonia toxic? - ANSWER-- The reaction of glutamate dehydrogenase is
favored towards use of alpha-ketoglutarate to make glutamate
- The TCA cycle shuts down due to a lack of alpha-ketoglutarate
(nothing to do with pH!)
α-ketoglutarate - ANSWER-a critical product of the TCA cycle in the mitochondria
protonephridia (flatworms) - ANSWER-an excretory system, such as the flame bulb
system of flatworms, consisting of a network of tubules lacking internal openings
insect digestive tract - ANSWER-malpighian tubules extend into hemolymph
mammalian kidney structure - ANSWER-
nephron structure - ANSWER-1. Blood enters glomerulus (Filtering process)
2. Filtrate enters Bowman's Capsule (Filtering process)
3. Proximal convoluted tubule (Reabsorption NaCl, nutrients, and water)
4. Loop of Henle (countercurrent exchange) (Down: water leaves via aquaporins
Up: reabsorbing salts, water stays because there are no aquaporins)
