Unit 2 Flashcards
Abiotic Characteristic of kelp forest
- Cold water all year
-High dissolved nutrients from upwelling
-High O2
Why are colder waters more favorable?
More dissolved oxygen
Greater diversity
What is the relationship between temp and dissolved oxygen?
Inverse relationship
As you increase the temperature, the amount of dissolved oxygen decreases.
Therefore, colder waters have more dissolved oxygen and therefore greater diversity
Range of tolerance for dissolved oxygen in fish
too low = fish cannot survive
The higher the better
Complexity of Kelp Forest
High vertical complexity!!!
-high stability
-high resillience
-high resistance
-high biodiversity
Kelp are macroalgae
Convergent evolution of plant-like body plan
-kelp are brown algae that photosynthesize and can grow up to more than 2 feet a day
Why have the northern CA kelp forest collapsed?
What is Thermoregulation and why is it important to organisms?
Thermoregulation is the ability to control your own temperature.
It is important to organisms because temperature is highly related to enzyme function.
-proteins fold and some of those folds are dependent on temperature
-they can denature when too hot
Graph the relationship between Enzyme Activity vs. Temperature
Three kinds of adaptations animals have to regulate their temperatures
1) Behavioral adaptations
2) Physiological adaptations
3) Morphological adaptations
Behavioral adaptation
Actions and behavioral strategies to maintain homeostasis
ex: basking, sheltering, shivering, migrating, panting, burrowing, etc..
Physiological adaptation
Internal changes/ internal biological processes
-Processes inside an animal’s body that helps it to survive in its environment
-ex: sweating, vasodilation when too hot, vasoconstriction when too cold, countercurrent exchange, and metabolism (thermogenesis)
Morphological adaptation
external characteristics of an animal’s body that help it survive in its environment
ex: blubber, thick fur, small ears in when too cold (limit time blood vessels spend in appendages), large ears when too hot (increase surface area for circulatory heat exchange)
Adaptations for being too hot/ strategies to reduce body temperature
-sweat
-dilation of blood vessels (vasodilation)
-panting
-burrow
-big ears
-Dormacy (estivation)
-wallowing (rolling in mud)
-body positioning
Adaptations for too cold/strategies to increase body temperature
vasoconstriction
countercurrent exchange
metabolism- increase metabolic rate
thick fur
blubber
basking
dormancy (hibernation)
body positioning
shivering
goosebumps
limit blood flow to extremities
Organisms either ______ or ______ to environmental conditions like temperature
regulate, conform
Regulators
keep internal environment constand
Examples of Regulators
river otters, humans, bears
Conformer
let internal environment match external environment
Examples of Conformers
largemouth bass, amphibians, reptiles
Graph of body temp vs ambient (environmental) temp for both conformers and regulators
x-axis: environmental temp
y-axis: internal body temp
Regulators: this should be a straight horizontal line because as the temperature in the environment increases, the internal body temp does not change
Conformers: positive linear line that shows how as the temperature in the environment increases, the body temp of a regulator also increases
Advantages of being a thermoconformer
-save a lot of energy
-don’t need to eat very much
-need to live in more consistent environments
-narrow range of habitats
Disadvantages of being a thermoconformer
-enzymes might not always act optimally
-limited environmental range
Advantages of being a thermoregulator
Can live in lots of variable environments
Wide range of habitats
Enzymes work optimally
Disadvantages of being a thermoregulator
takes a lot of energy to be independent of the environment and lots of energy to maintain internal body temp
Evolutionary tradeoffs of thermoregulators and conformers
thermoconformers: less energy, but limited environmental range
thermoregulators: more energy, but wider range of habitats
Thermogenesis and metabolism
biological processes to produce heat from energy
-dissipation of energy through production of heat
thermogenesis = heat production
-strategy to increase body temperature
Endotherm
Temperature can be controlled by biochemical processes (metabolism)
Can control temp by altering metabolic rate
ex: all birds and mammals
Ectotherms
Body temp is NOT controlled w/ metabolism
Heat source is primarily from the environment
Ex: reptiles, amphibians
What is the thermoneutral zone? Does this impact endotherms or ectotherms? How does metabolic rate change outside of thermoneutral zone?
Thermoneutral zone is the temperature range in which metabolic rate does not need to rise to maintain body temps
This impacts endotherms because their body temp is related to metabolic rate.
Metabolism increases below the lower critical temperature (LCT), primarily as a result of shivering heat production. Metabolism increases above the upper critical temperature (UCT) from active loss of heat through panting and evaporative cooling, as well as the direct effects of higher temperatures on cellular functions.
How does endotherm/ecotherm and size affect metabolic rate
Among endotherms, smaller animals tend to have higher per-gram basal metabolic rates (a “hotter” metabolism) than larger animals.
Endotherms tend to have basal high metabolic rates and high energy needs, thanks to their maintenance of a constant body temperature. Ectotherms of similar size tend to have much lower standard metabolic rates and energy requirements.
Metabolic rate
The amount of energy expended by an animal over a specific period of time is called its metabolic rate
Metabolic rate = respiration rate = how fast we burn calories or consume O2
Energy requirements related to body size
Among endotherms (animals that use body heat to maintain a constant internal temperature), the smaller the organism’s mass, the higher its basal metabolic rate is likely to be.
Marine mammals have ____________ metabolic requirements than terrestrial mammals because water causes heat loss faster than air
higher
-water causes heat loss 25x faster than air because of its specific heat
Homeostasis
a condition of balance of equilibrium within an internal environment
Dynamic equilibrium
conditions vary around a central tendency but never a constant condition
There is an acceptable _____ for homeostasis and dynamic equilibrium rather than a __________.
range, point
Are sea otters endotherms or ectotherms?
endotherms because they control their internal temperature w their metabolism
Sea Otters physical appearance
3 1/2 feet to 5 feet long
50-100 lbs
no blubber
very dense fur
How do sea otters maximize heat generation?
thermogenesis
they skip the step of making ATP and goes straight to making heat
What do sea otters need to maintain both metabolism and thermogenesis?
LOTS of food
What percentage of their body weight do otters need to eat every day in order to power metabolism and thermogenesis?
30%
What do sea otters normally eat?
Invertebrates: clams, crabs, urchins
What type of metabolism do sea otters have? Autotrophs or heterotrophs?
Heterotrophs
Where do most of your calories come from? Where do they go?
Food and they go to cellular respiration
Cellular respiration: transforms energy into organic molecules into ATP and heat
Cellular respiration
transforms energy in organic molecules into heat and ATP
Food (chemical energy) -> ATP (chemical energy)
Energy flows through biological systems through which law?
Law of thermodynamics
1st Law of thermodynamics
energy can be transferred and transformed but cannot be created nor destroyed
2nd Law of Thermodynamics
every energy transfer or transformation increases the entropy (disorder) of the universe
The second law states that there is loss of energy at each step of energy flow. This law also stands true in ecology as their is progressive decrease in energy at each trophic level.
Flow of energy and the second law of thermodynamics : In the food chain, according to the 10% rule, only 10% of energy is transferred to each trophic level. The rest of energy is lost as heat due to the process of respiration increasing the entropy of the system.
What is energy? Name four kinds
Energy is what makes matter move or change
-Chemical energy
-Electrical energy
-Solar energy (light)
-Thermal energy
How does energy transfer between trophic levels?
Only some energy is assimilated (60%), most is lost as heat or waste (40%)
Assimilated - Assimilation is the biomass (energy content generated per unit area) of the present trophic level after accounting for the energy lost due to incomplete ingestion of food, energy used for respiration, and energy lost as waste.
The amount of energy at each trophic level decreases as it moves through an ecosystem. As little as 10 percent of the energy at any trophic level is transferred to the next level; the rest is lost largely through metabolic processes as heat.
How does energy move between trophic levels? Energy can pass from one trophic level to the next when organic molecules from an organism’s body are eaten by another organism.
How are metabolic rates measured?
Gas exchange
You can measure metabolic rate by measuring how much oxygen was consumed and how much carbon dioxide was formed
estuary
where freshwater and salt water meet
Estuaries and their surrounding wetlands are bodies of water usually found where rivers meet the sea. Estuaries are home to unique plant and animal communities that have adapted to brackish water—a mixture of fresh water draining from the land and salty seawater.
salinity fluctates with tide
Osmoregulation
Process of maintaining salt and water balance (osmotic balance) across membranes in the body
Osmolarity and osmolarity of salt and freshwater
Osmolarity = concentration [solute]
(aka concentration of salt)
High osmolarity = salt water = high concentration of salt
Low osmolarity = freshwater = low concentration of salt
Predicting Salinity of a Flounder in an Estuary:
-if the flounder is an osmoCONFORMER, what will the data look like?
-if the flounder is an osmoREGULATOR, what will the data look like ?
Osmoconformer: positive linear line that shows that when the external salinity increases, the internal salinity also increases
Osmoregulator: straight horizontal line – regardless of the external salinity, the internal conditions are held constant
Osmoconformers
-Match their internal environment to the external environment
-Body fluids are kept isotonic with respect to their external environment
-Have a survivable range of salinities
-graphically represented by diagonal line
Ex.Most marine invertebrates such as starfish, jellyfish and lobsters
Osmoregulators
-Keep internal conditions constant
-Keep body fluids at constant internal osmotic environment in spite of external conditions
-have a range of salinity that does not require them to expend energy to keep internal conditions constant
-graphically represented by a straight line
Ex. Mammals
Otters can eat lots of things. What is the best foraging strategy and what does it depend on? (4 things)
Optimal foraging strategy: MAXIMIZES NET ENERGY GAIN (so reduces energy spent)
Depends on:
1) How long it takes to find (the quicker it takes to find the less energy is spent)
2) How many are there ? (the more prey easily accessible the less energy is spent)
3) How deep it is? (the deeper the longer the dive time = more energy spent)
4) How dangerous it is (best foraging strategy reduces risk of danger)
Optimal foraging strategy
Maximize net energy gain
net energy = energy gained - energy spent
What is the order that otters should prefer different prey items (4)
1) Cancer crabs
2) Red abalone
3) red sea urchins
4) kelp crabs
When an otter runs out of their preffered prey, what happens?
They prey switch!!! they move to the next best prey
cancer crabs -> red abalone -> red sea urchins -> kelp crabs
Metabolic rate vs dive duration relationship/graph
exponential relationship that as dive duration increases metabolic rate continuously increases
Two models that show pop growth
exponential growth model
logistic growth model
Exponential growth model
-no resource limitations
-unrealistic/ not sustainable
-population growth rate constantly increases
-per capita growth rate is constant
Population growth rate
change in population per time
(change in number of individuals/change in time)
of individuals added or lost to a population in a given time period (year)
Per capita growth rate
the average number of offspring an individual has over a given time (year)
Logistic Population Growth Model
Limited resources limit population growth over time
Population growth rate changes over time
What is the population GR as N approaches K?
zero
this is because as the population approaches carrying capacity it is no longer increasing
Inflection point
the maximum point of population growth
(k/2)
Carrying capacity
maximum size of a population that an ecosystem can sustain
Generally speaking what are feedbacks?
agents of stability or rapid change
Define negative feedbacks? Example?
Promote changes that lead back toward equilibrium
Ex: predator prey dynamics
“overshoot, undershoot, overshoot”
