Unfortunately this question is incomplete as it is a multiple choice question. The following options are provided:
<span>A) body cavity between body wall and digestive system
B) number of embryonic tissue layers
C) type of body symmetry
D) presence of Hox genes
E) degree of cephalization
The answer is D: presence of Hox genes
</span>
Hox genes are a group of genes that determine the basic structure and orientation of animals.
Answer:
Tight or occluding junctions This type of junction is also called zonula occludens and is the most apical structure in the epithelial cell. Zonula occludens describes, that there is a formed band of tight junctions which encircles every cell.
Explanation:
Let me go look this up ill be right back okay....
Answer:
B. Use the polymerase chain reaction (PCR) to make multiple copies of the DNA.
Explanation:
The scientist is to analyze a small sample of DNA, the most useful step to start this would be first the use of polymerase chain reaction to make various copies of that DNA sample. PCR is essential and quick process that gives a lot of copies within few hours. It uses the sample or target DNA, according to which the primers are designed. Taq polymerase and DNA polymerase are also used in the process, it consist of various cycles in which copies are made. There are three basic steps 'Denaturation', 'annealing', and 'extension'.
