What example of response!
I would think the public waters source due to bacteria contamination
28. bacteria and fungi.
29. answer 3
30. answer 2
Answer:
D
Explanation:
This involves a dihybrid inheritance I.e. two genes are being passed on. During meiosis, specifically, the Prophase stage, homologous chromosomes (similar but non-identical chromosomes received from each parent) line side by side. According to the question, one chromosome contains A and B alleles and its homologue, received by the other parent carries a and b alleles. This means that the diploid individual has a genotype AaBb for that gene.
According to Mendel's law of independent assortment, the alleles separate independently of one another into gametes. I.e. allele A and a separates into the gametes without affecting alleles B and b of the other gene.
Crossing-over, which is the exchange of chromosomal segment occurs between the two homologues. Hence, the exchange of chromosomal segments containing alleles in the individual will possibly produce four gametes with the genotypes: AB, Ab, aB, ab.
The correct answer is - D) covered by warm shallow seas.
The fact that the crinoids are have an abundance in the fossil records in Pennsylvania in the Mississippian Period, tells us that this area was covered with shallow and warm seas. The reason why we can get that conclusion is that the crinoids live only in that kind of environment, so it simply a logical conclusion.
The geological data is also confirming this, as it is easily noticeable in the layers that during this period of the geologic past, what is now Pennsylvania, was covered with shallow sea waters. Also, this waters were warm too, as the climate was warm and humid and that period, so it was a perfect environment for the crinoids to flourish.
