Kaplan Biology: Chapter 12 Flashcards
Co dominance
more than one dominant allele– you get “patches” where one allele is dominating (ex/ a paint horse)
incomplete dominance
no dominant alleles: heterozygous individuals have intermediate phenotypes (a roan horse)
5 conditions of hardy weinberg principle
1) large population
2) no mutation
3) no migration
4) random mating
5) all genes are equally successful at reproducing (NO NATURAL SELECTION)
Hardy weinberg principle for GENOTYPE frequency
P^2 + 2PQ + Q^2 = 1
hardy weinberg principle for ALLELE frequency
P + Q = 1
adaptive radiation
rapid rise of a number of different species from a common ancestor
disruptive selection
two extreme phenotypes are selected over the norm
stabilizing selection
a “medium” phenotype is selected over extremes
prezygotic mechanism
prevent formation of zygote completely
postzygotic mechanism
allows for gamete fusion but yield either nonviable or sterile offspring
mules are a result of a __zygotic mechanism
post. they are created, but are left sterile
convergent evolution
independent development of SIMILAR characteristics in two or more species that do not share a recent common ancestor
molecular clock model
method of measuring evolutionary time. the more SIMILAR the genomes, the more RECENT the two species separated from each other.
genetic leakage
flow of genes between species through hybrid offspring.
more SIMILAR the genomes, the more _____ the two species separated from each other.
more SIMILAR the genomes, the more RECENT the two species separated from each other.
analogous structure
independently evolved, but carry out the SAME FUNCTION ex/ bee wing and bat wing. bees and bats are not related at all but their wings have the same function: flying
homologous structure
evolved RELATEDLY, but different functions. Ex/ Walrus flipper and human forearm (flipper is used for swimming, and our arms have dexterity functions), but the same bone structure is in place.
What type of muscle fiber has a lot of mitochondria?
slow muscle fibers. they can contract harder and are used for continuous muscle contractions. They use aerobic respiration.
fast muscle fibers are more likely to operate on glycolytic respiration.
According to the passage, relative to slow-twitch fibers, fast-twitch fibers are likely to exhibit which property?
A.Greater Ca2+-pumping capacity
B.Increased capillary density
C.More mitochondria
D.Higher levels of oxygen-binding proteins
Greater Ca2+ pumping capacity. fast twitch fibers must be able to contract and relax quickly, and this can only happen if Ca2+ can be released and REMOVED from the sarcoplasm and back to the sarcoplasmic reticulum.
