In which situation will a mutation not persist or spread in a population? a-the mutation increases reproductive advantage b-the
mutation does not affect selection c-the mutation is always immediately lethal when it occurs d-the mutation is only lethal in the homozygous ressesive state
Lets rule out A first. If a species has a better reproduction rate it will spread through it's offspring through genes. B is also incorrect. D. the mutation is only lethal in the homozygous ressesive state - this can still spread if the species is not in the homozygous ressesive state. This leaves C. If it is always lethal the species will die and not have offspring to pass off the gene.
Population genetics is fundamental to our understanding of evolution, and mutations are essential raw materials for evolution. In this introduction to more detailed papers that follow, we aim to provide an oversight of the field. We review current knowledge on mutation rates and their harmful and beneficial effects on fitness and then consider theories that predict the fate of individual mutations or the consequences of mutation accumulation for quantitative traits. Many advances in the past built on models that treat the evolution of mutations at each DNA site independently, neglecting linkage of sites on chromosomes and interactions of effects between sites (epistasis). We review work that addresses these limitations, to predict how mutations interfere with each other. An understanding of the population genetics of mutations of individual loci and of traits affected by many loci helps in addressing many fundamental and applied questions: for example, how do organisms adapt to changing environments, how did sex evolve, which DNA sequences are medically important, why do we age, which genetic processes can generate new species or drive endangered species to extinction, and how should policy on levels of potentially harmful mutagens introduced into the environment by humans be determined?
<span>How many different types of offspring (genotypes) are possible as a result of this cross, according to the punnett square? The correct answer is 3.
With three alleles we have a higher number of possible combinations in creating a genotype. Notes: As you can count, there are 6 different genotypes & 4 different phenotypes for blood type.</span>
Four conditions are needed for natural selection to occur: reproduction, heredity, variation in fitness or organisms, variation in individual characters among members of the population. If they are met, natural selection automatically results.
In mitosis, when a single cell divide into two daughter cell and each daughter cells have a copy of chromosomes, there must first be the copying of the chromosomes from the parent cell and after that the chromosomes are separated or there is separation of chromosomes into each of the daughter cells.
