The relative location of four genes on a chromosome can be mapped from the following data on crossover frequencies Genes B and D Frequency of Crossover 5% Cand A 15% A and B 30% C and B 45% Cand D 50% Which of the following represents the relative positions of these four genes on the chromosome? 1. ABCD 2. ADCB 3. CABD 4. CBAD

3. CABD

Explanation:

The gene mapping refers to providing position to the genes on the chromosomes.  The first gene map was constructed by the Alfred Sturtevant on the basis of recombinant produces or recombination frequency which was calculated.

The gene mapping refers to providing position to the genes on the chromosomes.

In the given question to construct gene map:

1. Look for the highest recombination frequency that is 50% between the C and D.

2. Now look for second-highest value and place the gene accordingly.

3.Similarly, place the genes in the decreasing order of recombination frequency and this will result that the sequence of the genes is- CABD.

Thus, Option-3 is correct.

answer: decrease

a limiting factor is the one which decrease the abundance, distribution and causes extinction of the population of species in a ecosystem. here, predators including hawks, owls and snakes are the limiting factor for the population of mexican free tailed bat.   although bats are nocturnal animals as they forge for food at night these predators also may remain active during night which can decrease the population of the mexican free-tailed bats. also, these bats eat only one type of insects that are moths. the food can also be a limiting factor as all 400 members are dependent upon same type of food needs that are moths. the decrease in the moth population can cause decrease in population size of the mexican free-tailed bats.

therefore, the scenarios will most likely to decrease the population size of the mexican free-tailed bats.