Allele frequency refers to the fraction of individuals with a particular version of a given gene. what effect does genetic drift have on the allele frequency of a population? a. it causes the allele frequency to resemble that of a small number of individuals that became separated from the rest of the population. b. it causes random changes and the allele frequency of certain traits may increase or decrease. c. it increases the frequency of alleles that improve a species' survival in a particular environment. d. it greatly reduces the total population, which increases the effects of natural selection on allele frequency.

The human genome project is devoted to mapping the general dna sequence of our species. this could lead to the development of new medicines, as well as the possibility of using gene therapy to treat certain diseases. however, there are some ethical issues surrounding the mapping of individual genomes. one concern is a) that your genes may change over time, making the project useless. b) that insurance companies could discriminate based on genetic make-up. c) that since this has never been done before, we should probably not do it now. d) that sequencing our individual genomes is so expensive, it is a counter-productive strategy.

The embryos of a bird, a reptile, and a mammal are similar in appearance. how does comparing the physical appearance of embryos of different species support the theory of evolution? a. it shows that these organisms share a common ancestor. b. it provides evidence that these organisms eat the same foods. c. it shows that these organisms share the same habitat. d. it provides evidence that these organisms suffered a genetic mutation.

Astudent from one of the research labs is having trouble preparing a slide for examination and photographing. the bacterial slide that he has brought to you was prepared using a commercially purchased stain. he has asked for your in determining what he is doing wrong so that he can change the lab protocols and continue on with his project. after examining the slide under oil immersion, you determine that no bacteria are present even though the student is able to show you the culture he used to make that slide that has visible growth in the liquid medium. which of the following statements does not explain the fact that there are no bacteria present on the student’s slide? by not allowing a glass slide to completely air dry before heat fixation, the flame will cause the surrounding water to boil and this will damage the bacterial cell. overheating during the fixation step boiled the water within the bacterial cells and resulted in the cells bursting. insufficient heating of the slide did not drive out the thin layer of water and this resulted in minimal bonding between the bacteria and the glass slide. rinsing with alcohol during the washing step stripped the bacteria off the glass slide. rinsing with alcohol during the washing step stripped the bacteria off the glass slide.