The recessive mutant allele that causes cystic fibrosis is much more frequent in Caucasians population than in other world populations. Some scientists believe heterozygotes must have had a survival advantage during plagues such as cholera that occasionally swept through this population. What concept does this illustrate?

#Question id: 18379

#Unit 12. Applied Biology

#Question id: 11814

#Unit 6. System Physiology – Plant

Simplified biosynthetic pathway for cytokinin biosynthesis followed given such steps;

a) isopentenyl transferase (IPT), is the addition of the isopentenyl side chain from DMAPP (dimethylallyl diphosphate) to an adenosine moiety (AMP)

b) iPRTP or iPRDP is converted to ZTP or ZDP respectively by cytochrome P450 monooxygenase  and eventually is converted to zeatin

c) The ribotide and riboside forms of trans-zeatin can be interconverted, and free transzeatin can be formed from the ribotide by the LONELY GUY (LOG) family of cytokinin

Which of the following steps is true of the cytokinin biosynthesis?

#Question id: 4866

#Unit 8. Inheritance Biology

In a certain diploid plant, the three loci A, B, and C are linked as follows: Assuming 100%   interference, if the plant with genotype ABC/abc is test cross, what proportion of the progeny will be of the genotype a b c/a b c?

#Question id: 5813

#Unit 8. Inheritance Biology

Examples of environmental mutagens include:

#Question id: 2967

#Unit 2. Cellular Organization

G1 is associated with which of the following cellular events?