Unit 2 - Thermoregulation, Metabolism, Energy & Homeostasis Flashcards
examples of structure
tissues / food webs
examples of function
thermoregulation / ecosystem stability
subcategories of physiology
bioenergetics and thermoregulation
subcategories of populations and communities
predator-prey interactions and population cycles
subcategories of ecosystems
food webs, climate change, ocean acidification, trophic cascades
How many feet can kelp grow a day?
2 feet
Kelp convergently evolved a ____-like body plan.
plant
Kelp are _______.
macro algae
What are some abiotic characteristics of the Kelp forest?
-cold water all year round (Northern California)
-high dissolved nutrients (upwelling)
-high O2
What describes the process of deep underwater ocean currents bringing nutrients up to the surface and producing a lot of growth?
upwelling
What is the relationship between temperature and dissolved Oxygen (DO)?
inverse relationship (colder water = more dissolved Oxygen)
Why is dissolved Oxygen important to underwater ecosystems? CO2?
DO: animals (fish, shrimp, starfish)
DCO2: plants
All dissolved gases are lower in ______ waters, not just CO2.
warmer
What ppm level of dissolved Oxygen supports abundant fish populations? What ppm level is too low for fish populations?
> 9.00ppm; <3.00ppm
Where are the most productive marine ecosystems found on the globe?
near the poles (cold places); NOT near the equator
Why are most marine ecosystems found in cold places?
there is more plant productivity in cold places that have lots of dissolved CO2 in their waters
What is net primary production (NPP) a measure of?
plant biomass
Where are most biodiverse terrestrial ecosystems found?
near the equator
What type of organism keeps their internal environment constant regardless of their external environment?
regulator (river otter)
What type of organism takes their internal environment and matches it with their external environment?
conformer (largemouth bass)
Do conformers’ temperatures fluctuate a lot?
NOT ALWAYS - might just go to the temperature they like and stay there
Do conformers completely give into their environment?
no they have some control over it—migration
Why is the temperature control of thermoregulates important to organisms?
-proper enzyme function (denaturation when it gets too hot)
-proteins
Why is it good for organisms to have fast acting enzymes?
to speed up their internal processes
Why doesn’t the enzymatic rate keep increasing with temperature?
the protein can get too hot/denature–> will lose its function & shape
What are the advantages of being a thermoregulator?
-removed from environment temperature changes
-enzymes are always functioning at their optimal level – everything happens normal and as fast as possible
-has a wider range of suitable environements
What are the advantages of being a thermoconformer?
-don’t need to spend a lot of resources/energy to keep their body temperature constant (temperature regulation requires a lot of energy)
What are some strategies to increase body temperature?
-blubber
-thick fur
-vasoconstriction - limit blood flow to extremities
-countercurrent exchange
-dormancy (hibernation)
-body positioning
-basking
-metabolism (thermogenesis)
-goosebumps
-increase metabolic rate
-shivering
What are some strategies to reduce body temperature?
-sweating
-panting
dormancy (estivation)
-body positioning
-vasodilation
-wallowing
-surface area for circulatory heat exchange
-burrowing
What are the three types of environmental adaptations?
morphological
physiological
behavioral
type of adaptation: involves changing a physical aspect of an organism; often related to a change in the organism’s physical environment (ex: developing wings for flight, fins for swimming, powerful legs for jumping)
morphological
type of adaptation: change affecting the way an organism naturally acts; could be a case of a change in the surrounding environment or from the actions of another species (ex: feeding habits, communication methods, reproductive strategies)
behavioral
type of adaptation: involve a physical change to a species BUT not always seen in organisms’ appearance; driven by either a change to the environment or behavior of another species (ex: developing greater intelligence; improving senses)
physiological
What is a great example of thermoregulation in North Carolina?
gators - stick their snouts out of frozen lake to survive
What happens to internal processes like respiration in a frog (thermoconformer) as temperatures drop?
all chemical reactions and enzymes will be acting slower
What happens to internal processes like respiration in a fox (thermoregulator) as temperatures drop?
might speed up or stay the same
Tradeoff of thermoregulation?
takes a lot of energy to be independent of your environment
Pro of thermoregulation?
can live in lots or variable environments
Tradeoff of thermoconformers?
need to live in more consistent environments or have to be able to deal with large swings in their enzyme function
Pro of thermoconformers?
they save a lot of energy and don’t have to eat very much
What is used to regulate an organisms internal temperature?
metabolism
What do we, as humans, use to influence our temperature?
metabolism
Humans are (regulators or conformers)?
regulators
Between what temperature range, do humans experience the least amount of metabolism?
between 27 and 36
What happens below the critical temperature?
animal expends energy to produce metabolic heat; metabolism increases
What happens above the critical temperature?
animal must expend energy to lose heat by panting or sweating; metabolism increases
Why can’t we keep increasing our metabolism forever?
it will cause death (hypo or hyperthermia)
In what zone is body temperature regulated by passive mechanisms, such as heat loss through the skin?
thermoneutral zone
Cellular respiration formula:
C6H12O6 + 6O2 –> 6CO2 + ATP
How are metabolic rates measured in humans?
stick a person on the treadmill and see how much Oxygen they consume OR CO2 they expel
How are metabolic rates measured in terrestrial vs aquatic animals?
terrestrial: stick them on treadmill like humans
aquatic: send them down to bottom of tank to do a task and then when they come up to the respiratory dome measure their O2/CO2
What is another name for the therm-neutral zone/lowest metabolic rate?
basal metabolic rate
What is the temperature range in which metabolic rate does NOT need to rise to maintain body temperature?
therm-neutral zone
Metabolic rate is the same as _______ rate.
respiration
definition: how fast we burn calories (sugar)
metabolic rate
Outside of therm-neutral zone (hotter or colder), what happens?
have to increase metabolic rate / spend more energy (why Anarticans eat 8000 calories a day)
definition: organism whose internal temperature can be controlled by altering metabolic rate
endotherm
Is metabolism the only thing endotherms use to control temperature?
no
common examples of endotherms
all birds & mammals
definition: body temperature is NOT controlled by metabolism
ectotherm
common examples of ectotherms
reptiles, amphibians, fish, and invertebrates
Since ectotherms do NOT use their metabolism to control body temperature, what do they use instead?
behavioral and physiological adaptations
What is a common example of an organism that is between endotherm and ectotherm?
some INSECTS, particularly bumble bees:
-they shiver themselves into a warmer temperature in the mornings
-they twitch their muscles to generate heat, which by nature increases their metabolic rate
homeo or poikilotherm:
-internal temp remains very stable
-have a small range of tolerable temps
-ALL endotherms and a few ectotherms
homeotherm
homeo or poikilotherm:
-do NOT require their internal temp to remain constant
-no permanent effects (though biochemical processes will speed up or slow down with temp)
poikilotherm
What needs to be true if you are an ectotherm that is a homeotherm?
environment needs to be stable in a tolerable range
What is a good example of a poikilotherm?
organisms in the intertidal zone because they are exposed to a huge range of temperatures (alligator)
Who needs more calories: a tiger or cat & why?
tiger because the bigger the size of organisms the faster their metabolic rate is
Bigger organisms burn ____ calories over a period of time than small organisms.
more
At a similar size, do endo or ectotherms have a higher metabolic rate? Why?
endotherms because they have to spend more energy regulating their internal body temperature while ectotherms don’t have to spend energy to conform
Who has a larger range of body sizes: endo or ectotherms?
ectotherms
What species do you expect to have a higher energy requirement per kg, a large or small endotherm?
small endotherm
Why do small endotherms have higher energy requirements per kg?
small organisms tend to lose heat more easily due to their higher surface area to volume ratio, so they have to burn more calories to stay warm (its a lot easier for larger organisms to retain heat)
metabolic rate of ____ endotherm: 5.62 kcal/hr/kg
metabolic rate of ____ endotherm: 1.29 kcal/hr/kg
small; large
Do marine or terrestrial mammals have a higher metabolic rate?
marine
Why do marine mammals have a higher metabolic rate than terrestrial?
water causes heat loss 25x faster than air because of its specific heat
Does a carnivore or herbivore have a higher metabolic rate?
carnivore (need more energy)
What is the smallest carnivorous marine mammal that exists?
sea otter
What do sea otters mainly feed on?
invertebrates (clams, crabs, urchins) & they have a favorite rock
Do sea otters tend to go on land?
no
Are sea otters endo or ectotherms?
endotherm (really high metabolic rate)
what animal is being described:
3.5-5 ft long
50-100 lbs
no blubber
very DENSE fur (>1M hairs/sq inch)
endotherm
need to eat 30% of their body weight every day
sea otter
How do sea otters maximize heat generation?
thermogenesis–they skip the step of making ATP and go straight to making heat
description: respiration that burns calories solely for heat
thermogenesis
How much faster do sea otters burn calories compared to humans?
3x (like humans eating 15,000 calories a day)
definition: process that transforms energy in organic molecules into ATP and heat
cellular respiration
What process converts food (chemical energy) into ATP (chemical energy)?
cellular respiration
Which molecule contains lots of C-C and C-H bonds with high energy electrons?
glucose
Which molecule contains only C double bound to O bonds with low energy electrons?
carbon dioxide
What is a common way to store potential energy?
a chemical bond
When bonds are broken, what happens to the energy stored in them?
energy is released and can be used by cells
Which molecule has more potential energy: glucose, starch/carbohydrate, or carbon dioxide?
starch/carbohydrate
In cellular respiration, does all the energy in food turn into ATP?
no, energy is lost along the way
Energy flows through biological systems according to what?
laws of thermodynamics
law of thermodynamics? energy can be transferred or transformed, but not created or destroyed
first law of thermodynamics
law of thermodynamics? energy transfer or transformation increases the entropy (disorder) of the universe
second law of thermodynamics
What are some different types of energy?
chemical: chemical potential energy stored in molecular bonds - energy can be released when bonds are broken
electrical: based on charge/electrical gradients
solar (light): photosynthesis
thermal: kinetic energy
If only some energy released is useful what happens to the rest?
most is dissipated or lost as heat
About how much energy in the glucose that enters cellular respiration do you think is assimilated?
60%
What are some ways that energy can be released as heat?
cellular work, biosynthesis, cellular respiration, digestion & absorption
Thermoregulation is a ______ feedback loop.
negative
_____ feedback: a system that promotes stability by counteracting a stimulus (overshoot, undershoot, overshoot)
negative
What happens in thermoregulation when body temperature decreases?
heating mechanisms are activated (shivering) which in turn increases body temperature
What happens in thermoregulation when body temperature increases?
cooling mechanisms are activated (sweating)
When we overshoot body temperature, there is a system in place to _______ the condition.
stabilize
definition: a dynamic equilibrium which is actively regulated to maintain a variable at a constant level
homeostasis
Homeostasis is more of an acceptable _______ than a _____.
range; point
Can the range of homeostasis vary?
yes, poikilotherms have a very wide range
What organisms keep their internal conditions constant (dynamic equilibrium)?
regulators
What organisms match their internal environment to their external environment?
conformers
Organisms either ____ or _____ to environmental conditions like temperature.
regulate; conform
Even though regulation is costly, it’s beneficial in the way it maintains ________.
homeostasis
______ depend on heat exchange with the external environment and require very little food. Their internal temperature changes when the environmental temperature changes.
ectotherms
What is the place where a freshwater river meets a body of saltwater?
estuary
What are some unique characteristics of an estuary?
-brackish water
-at high tide, estuary is a LOT saltier
-really variable environment where salinity changes with the tide & organisms have to cope with the changing environment
What do sea otters do for the majority of their day?
rest & feed (to keep themselves warm)
What do sea otters not do for the majority of the day?
grooming / swimming (they do not waste excess energy)
Ultimately, otters should be eating the things that give them the _____ energy gained for the ____ amount of energy spent.
most; least
Predators target prey/forage based on their ability to maximize what?
energy gain
Tradeoff of abalones as prey?
even though they contain the highest amount of calories, they take the LONGEST dive times to find
What things do we need to account for when determining how much energy it takes to get/eat a prey item?
-how long it takes to find
-how deep it is
-how hard it is to open/eat
-how dangerous it is
definition: theory that predators use foraging strategies to maximize energy gain
optimal foraging theory
Relationship between dive duration and Oxygen consumed?
positive/direct
What is the order of preferred otter prey items?
(1) cancer crab
(2) red abalone
(3) Red Sea urchin
(4) kelp crab
What do regulators look like on a graph?
a fairly straight line parallel to x-axis
What do conformers look like on a graph?
positively sloped line / negatively sloped line
What does osmoregulation measure?
body fluid solute concentrations
definition: the process of maintaining salt and water balance across membranes within the body
osmoregulation
