Which of the following statements is an example of genetic drift?

a. Allele g for fat production increases in a small population because birds with more body fat have higher survivorship in a harsh winter.

b. Random mutation increases the frequency of allele A in one population but not in another.

c. Allele R reaches a frequency of 1.0 because individuals with genotype rr are sterile.

d. Allele m is lost when a virus kills all but a few individuals and just by chance none of the survivors possess allele m

#Question id: 2810

#Unit 2. Cellular Organization

Which of the following steps is required to generate a knockout mouse?

a. microinjection of DNA into the pronucleus of a fertilized mouse egg

b. introduction of DNA into mouse embryonic stem cells

c. selection for cells containing the gene targeted insertion

d. expression of Cre protein during embryonic development

#Question id: 10144

#Unit 6. System Physiology – Plant

Choose the incorrect statements about photosynthesis dark reaction ?

#Question id: 19330

#Unit 12. Applied Biology

#Question id: 11810

#Unit 6. System Physiology – Plant

An experiment was done to see the effect of auxin: cytokinin ratios on morphogenesis can also be seen in crown gall tumors by mutation of the T-DNA of the Agrobacterium Ti plasmid,

I) Mutating the ipt gene (the tmr locus) of the Ti plasmid blocks zeatin biosynthesis in the infected cells

II) mutating either of the genes for auxin biosynthesis (tms locus)

Given some results about these above mutations ,

a) equal auxin to cytokinin ratio form undifferentiated callus tissue

b) high auxin:cytokinin ratio in the tumor cells causes the proliferation of roots instead of undifferentiated callus tissue

c) lowers the auxin:cytokinin ratio and stimulates the proliferation of shoots

What would be the result of these two mutation ?

#Question id: 23569

#Unit 8. Inheritance Biology