ES 3033 Exam 2

natural selection

differential survival/reproduction within a population that result from interactions with the environment

adaptation

heritable trait of an organism that has evolved over time by natural selection; contributes to fitness of an organism

fitness

measurement of the contribution of an individual to future generations

evolution

change in gene frequency over time

what caused the peppered moth to change color patterns?

industrial melanism

typica peppered moth

carbonaria peppered moth

what is evidence for evolutionary change?

fossil records, morphological convergence, morphological divergence, domestication, antibiotic resistant bacteria, GA cockroaches

simple organisms are found in _____ rocks, complex organisms are found in _____.

oldest; newer

what is morphological convergence?

independent evolution of similar morphological adaptations to similar environmental challenges in unrelated organisms

sharks/dolphins and birds/butterflies are examples of morphological ________.

convergence

what is morphological divergence?

over time, populations diverge in morphological traits that characterize their species; change from common ancestor body form; may or may not result in speciation.

the galapagos finches' beaks are an example of morphological _____.

divergence

what is artificial selection?

a process by which humans use animal/plant breeding to selectively develop particular traits or characteristics by choosing and controlling individual reproduction.

what are the requirements for evolution?

population, heritable traits, genetic variation, selective pressure, and time

what theory did jean baptiste lamarck come up with?

acquired characteristics-modifications produced in an individual as a result of an environmental influence

what is a genotype?

genetic makeup of an organism

what is a phenotype?

the physical/chemical expression of characteristics

what are alleles?

one of two or more alternate forms of a gene

what is the dominant allele?

the expressed allele; denoted with an uppercase letter

what is the recessive allele?

the masked allele; denoted with a lowercase letter

what does homozygous mean?

two identical alleles of a gene (AA or aa).

what does heterozygous mean?

two different alleles of a gene (Aa_

what does the hardy-weinburg principle state?

under certain conditions of stability, both allele frequencies and genotypic ratios remain constant from generation to generation in sexually reproducing populations

what are some conditions of stability?

a large population reduces genetic drift, no mutations, no immigration, no selective pressure, random mating

what is genetic drift?

change in allele frequencies due to chance or random events

what is a recessive disorder?

2 copies of an abnormal recessive allele must be present in order for disease or trait to develop

in hardy-weinburg, how are recessive disorders characterized?

q^2

in hardy-weinburg, how are carriers characterized?

2pq

in hardy-weinburg, what does p represent?

frequency of the dominant allele in the population

in hardy-weinburg, what does q represent?

frequency of the recessive allele in the population

in hardy-weinburg, what does p^2 represent?

frequency of homozygous dominant individuals in a population

in hardy-weinburg, what does 2pq represent?

frequency of heterozygous individuals in a population

in hardy-weinburg, what does q^2 represent?

frequency of homozygous recessive individuals in a population

what is the hardy-weinburg equation?

what is directional selection?

mean shifts

what is an example of directional selection?

galapagos finch beaks

what is stabilizing selection?

the mean does not change

what is an example of stabilizing selection?

human birth weight

what is disruptive selection?

the mean does not change

what is an example of disruptive selection?

mocker swallowtail butterflies

in mocker swallowtail butterflies, males are ____ and females are ____

monomorphic; polymorphic

which selection has bimodal distribution?

disruptive

what is the biological species concept?

a species is a group of organisms that can potentially interbreed with one another to produce vital, fertile offspring.

what are examples of prezygotic mechanisms of reproductive isolation?

habitat, temporal, behavioral, gametic, mechanical

what are examples of postzygotic mechanisms of reproductive isolation?

hybrids do not develop or are sterile

what is speciation?

occurs as a subset of an original population, and becomes reproductively isolated from other subsets of the original population by some mechanisms of reproductive isolation

what is the most common form of speciation?

allopatric speciation

which form of speciation needs a physical barrier such as mountains, deserts, glaciers?

allopatric speciation

which form of speciation involves populations getting separated by habitat changes, and may interbreed but develop differently?

parapatric speciation

which form of speciation involves reproductive isolation that occurs in the original population with no physical barrier?

sympatric speciation

what is polyploidy?

having more than two full sets of chromosomes.

Is polyploidy more common in plants or animals?

plants

polyploidy diagram

what is homeostasis?

regulation of internal environment, maintenance of appropriate conditions when faced with a changing external environment

temperature, pH, ion balance, water balance, dissolved oxygen, and glucose concentration are all examples of factors that are regulated by:

homeostasis

_________ is used to maintain conditions at a set point or optimal range

negative feedback

what is thermoregulation?

maintenance of an internal temperature within appropriate limits

the temperature coefficient can be denoted by

Q10

what is temperature coefficient?

measure of the rate of change of a system due to an increase in temperature by 10°C

what is the heat budget equation?

what is "Hm" in the heat budget equation?

metabolic heat
-generated internally
-oxidation of carbs, fats, proteins

what is "Hcd" in the heat budget equation?

conduction
-direct physical contact
-temperature gradient

what is thermal conductivity?

measure of the ability of a material to conduct heat

what is "Hcv" in the heat budget equation?

convection
-solid body; moving fluid

what is a fluid?

a substance that has no fixed shape and yields easily to external pressure

what are the two types of convection?

natural and forced

what is "Hr" in the heat budget equation?

radiation

what is "He" in the heat budget equation?

evaporation

what is the heat of vaporization?

energy required to change the state from liquid to vapor

what is the temperature regulation equation for plants?

Hs= ±Hcd±Hcv±Hr-He

how else can annual plants be classified as?

"stress avoidance"

why did we talk about the oval leaf fan petal?

dormancy during high temperatures

what is dormancy?

germination block; delayed germination to prevent emergence under unfavorable conditions

are seeds durable?

yes

why is the svalbard global seed vault important?

it stores the worlds' seeds

what is ICARDA?

international center for agriculture research in dry areas

how else can perennial plants be classified?

stress resistance

open growth form, small leaves, transpiration, drought deciduous, dense pubescence, and paraheliotropism are all adaptations to ____ temperatures.

high

why is open growth form a good adaptation for high temperatures?

reduces heat gain by conduction, maximizes air movement through plant, increases heat loss by convection

why are small leaves a good adaptation for high temperatures?

increases heat loss by convection due to large surface area to volume ratio; reduces moisture loss

why is transpiration a good adaptation for high temperatures?

loss of H20 from plant in form of water vapor; evaporative cooling

where can stomata be found on the plant?

the surface of the leaf

what is paraheliotropism?

plants orient leaves to minimize incoming solar exposure

what is heliotropism?

directional growth of a plant in response to sunlight

what is dense pubescence?

reflects IR; does not gain as much heat from sun; low solar absorptance

plants that use dense pubescence have more dense hairs in the _____, and less dense hairs in the _____.

summer; winter

parallel orientation is an adaptation for ____ temperatures.

high

what are some plant adaptations to cold temperatures?

dark pigments, cushion growth form, diaheliotropism, dense pubescence, supercooling, winter deciduous, dehydration/extracellular ice formation

cushion growth form

dark pigments on plants help to:

maximize heat gain

what is diaheliotropism?

maximizes solar exposure through leaf orientation

why did we talk about the eastern skunk cabbage?

it melts the snow around the plant during the winter

what happens during supercooling?

solutes help reduce ice formation, and ice-binding protein production occurs through cold acclimation

what is the temperature regulation equation for animals?

Hs=Hm±Hcd±Hcv±Hr-He

what is a poikilotherm?

body temperature fluctuates with environmental temperatures

what is a homeotherm?

maintenance of fairly constant body temperature within narrow range

what are ectotherms?

control of body temperature through heat exchange with external environment

what kind of animals does this describe?

-low energy lifestyle
-minimal "Hm" (metabolic heat)
-most are poikilothermic
-dependence on a stable environment for metabolic rate and activity

ectotherms

true or false: ectotherms are larger in size than endotherms.

false: they are usually smaller.