exam 2

weather

short term variation in temperature and precipitation (hours or days)

climate

long term typical atmospheric conditions through the year (measured over many years)

example of events that can be rare but have large effects

tsunamis

example of some variation occurring in regular intervals

forest fires

large-scale spatial variation

impacted by factors like climate, land topography, and soil type

small-scale spatial variation

impacted by factors like plant structure and animal behavior

the faster an individual moves through space and the smaller the scale of spatial variation the ?

shorter the temporal scale of variation

all phenotypes result from ?

genes interacting with environments

environmentally induced phenotypes have a genetic ?

basis

a phenotype well-suited to one environment may be ? suited to other environments

poorly

phenotypic trade-off

a situation in which a given phenotype experiences higher fitness in one environment, whereas other phenotypes experience higher fitness in other environments

phenotypic plasticity

the ability of a single genotype to produce multiple phenotypes

phenotypic plasticity allows organisms to achieve ? if environmental conditions vary

homeostasis

natural selection favors the evolution of ? if the environmental variation results in ?

phenotypic plasticity; phenotypic trade-offs

phenotypic plasticity example

Gray tree frog tadpoles produce a phenotype that allows fast escape when predators are present and fast growth when predators are absent.

what phenotype is favored if spatial variation is not common

single phenotype

acclimation

an environmentally induced change in an individual's physiology

slow responses to acclimation

change in morphology (body shape) and life history (time to sexual maturity)

rapid responses to acclimation are ? whereas slow responses are ?

reversible; irreversible

species alter their ? ? and ? in response to the presence of predators (adaptation)

growth, body shape, and behaviors

example of adaptation

when Virginia pepperweed is eaten by herbivores, the plant develops leaf hairs which makes the leaves difficult to consume

variation in resource example

the Burmese python may come across a meal once a month. when a rodent is consumed, the snake doubles the length of its intestine and quadruples its heart size to accommodate the extra tissue

hermaphrodites

individuals that produce both female and male gametes; individuals are able to fertilize their eggs with their own sperm (self-compatible)

inbreeding depression

the decrease in fitness caused by matings between close relatives due to offspring inheriting deleterious alleles from both the egg and the sperm

organisms cam adjust their physiology to maintain activity across environmental temperatures

example: isoenzymes in goldfish

microhabitats

locations within a habitat that differ in environmental conditions from the rest of the habitats

microhabitats example

the desert iguana regulates its body temperature by basking on rocks, seeking shade, or burrowing in the ground

if plants are scarce to water, how do they adapt to their environment?

they close their stomata or grow longer roots using energy and materials

migration

seasonal movement of animals from one region to another.

monarch butterflies example

they migrate to wintering areas in southern north america and to the north during the summer

dormancy

a condition in which organisms dramatically reduce their metabolic processes

4 types of dormancy

diapause, hibernation, torpor, aestivation

diapause

involves a partial or complete physiological shutdown in response to unfavorable conditions; common in insects

hibernation

individuals reduce the energetic costs of being active by lowering heart rate and decreasing body temperatures; common in mammals

torpor

a brief period of dormancy that occurs in birds and mammals in which individuals reduce their activity and their body temperature

aestivation

the shutting down of metabolic processes during the summer in response to hot or dry conditions

foraging

behavior associated with recognizing, searching for, capturing, and consuming food (plastic behavior)

animals have 4 responses to food variation in space and time

central place foraging, risk-sensitive foraging, optimal diet composition, diet mixing

central place foraging

foraging behavior in which acquired food is brought to a central place, such as a nest with young

central place foraging example

a nest with young birds

traveling time

the time needed to travel round-trip to site with resources

searching time

the time spent obtaining food at a site

risk-sensitive foraging

foraging behavior that is influenced by the presence of predators

sensitive foraging example

creek chub feed on tubifex worms, but locations with worms also contain more predators

optimal diet composition

most animals do not consume a single food item, and base their diet decisions on handling time in addition to the energetic and nutritional value of various resources.

handling time

the amount of time that a predator takes to consume a captured prey

diet mixing

some foragers consume a varied diet because one type of food might not provide all of the necessary nutrients.

diet mixing example

humans combine food items to consume all essential amino acids

adaptation

seemingly good fit of the organism to the environment

water is densest at

4ºC

viscosity

the thickness of a fluid that causes objects to encounter resistance as they move through it

water's viscosity is

high

solutes

dissolved substances in water

semipermeable membrane

membranes that allow only particular molecules to pass through

osmosis

movement of water across a semipermeable membrane

osmotic potential

the force with which a solution attracts water by osmosis

osmoregulation

mechanisms organisms use to maintain a proper solute balance

hyperosmotic

tissue solute concentrations are higher than surrounding water

hyposmotic

tissue solute concentrations are lower than surrounding water

sharks and rays convert ammonia into what?

urea

salt balance in plants example

mangrove trees have high concentration of organic solutes in their roots and secrete salt from their leaves

aquatic plants use bicarbonate or carbonate for what

photosynthesis

countercurrent circulation

adaptation where blood and water flow in opposite directions so that the concentration of O2 in water is always greater than the concentration in blood

anaerobic/anoxic

environment becomes completely without oxygen

thermophilic

organisms living up to 110ºC

glycerol and glycoproteins

chemicals present in some animals that prevent freezing by reducing strength of hydrogen bonds or via supercooling

thermal optima

the range of temperatures in which an organism best performs

isoenzymes

different enzymes that catalyze same reaction

coral bleaching

loss of color in corals as a result of the corals expelling their symbiotic algae

cohesion

the mutual attraction of water molecules; allows water to move up through empty remains of xylem cells

root pressure

when osmotic potential in the roots of a plant draws in water from the soil and forces it into the xylem elements

transpiration

leaves can generate water potential as water evaporates from the surfaces of leaf cells

cohesion-tension theory

the mechanism of water movement from roots to leaves due to water cohesion and water tension

stomata

small openings on leaf surfaces that are points of entry for CO2 and exit points for water vapor; bordered by guard cells that and open and close each stoma

electromagnetic radiation

energy from the sun, packaged in small particle-like units called photons

photosynthetically active region

wavelengths of light that are suitable for photosynthesis

chloroplast

cell organelles found in eukaryotic photosynthesis organisms

chlorophylls and carotenoids are pigments inside ?

the thylakoids absorb light

chlorophylls absorb ? and reflect ?

red/violet light; green/blue light

chlorophyll a is found in ? and primarily responsible for ?

all plants; photosynthesis

chlorophylls b, c, d, f are ? pigments

accessory

chlorophylls b, c, d, f capture light energy and pass it to ?

chlorophyll a

carotenoids reflect ?

orange/red light

carotenoids allow plants to absorb ?

a wider range of solar energy

photosynthesis occurs in two steps ? and ?

light reactions; Calvin cycle

Calvin Cycle takes place in the ?

stroma of the chloroplasts

the energy in ATP and NADPH is used to convert CO2 into ?

glucose

Calvin Cycle C3

most plants/ most common

uses Rubisco

inefficient

ideal for wet/cool climates

Calvin Cycle C4

grasses, sedges

derived

Pep and OAA

reactions physically separated

ideal for hot/dry climates

Calvin Cycle CAM

family Crassulaceae (stonecrops)

derived

Pep and OAA

temporal separation of reactions

ideal for hot/dry climates

homeostasis

an organism's ability to maintain steady internal conditions when outside conditions change

negative feedback

the action of internal response mechanisms that restores a system to a desired state, or set point, when the system deviates from that state

negative feedback example

in mammals, the hypothalamus triggers increased metabolism when body temperature is below 37ºC and sweating when body temperature is above 37ºC

animals acquire ? in the water and food they consume

mineral ions

water intake and urine excretion eliminate excess ?

salts

water and salt balance example

the desert kangaroo rat conserves water by hunting during the night and staying below ground during the day

organisms that do not have access to fresh water (marine iguana) eliminate the salt in their drinking water through ?

specialized secreting organs

most aquatic animals eliminate excess nitrogen as ?

ammonia radiati

mammals produce ?

urea

birds and reptiles produce ?

uric acid