Answer:
Threonine has two chiral centers.
The correct options are c. carbon b and d. carbon c
Explanation:
Chiral centers are those that have four different groups of atoms bonded to it. Carbon a has three atoms of hydrogen attached to it so it can't be a chiral carbon. It isn't the carboxyl carbon either since it is double bonded to oxygen. And the amino nitrogen does not qualify anyway because it is bonded to three different groups of atoms, not four.
Answer:
Both options are true.
Explanation:
The cylindrical epithelium is a simple epithelium, which is characterized by having a cell layer, where all the cells are supported on the basement membrane, and its nucleus has reverse polarization in relation to the rest of the cells of our body, that is, they are found in a not very common position.
Simple cylindrical epithelia are found in areas of absorption or assimilation and exchange of gases or nutrients, since this shape is what allows them optimal diffusion through the epithelium, an example of the tissues in which this cellular architecture is found. They are the intestinal tract and the respiratory tract.
In the case of pseudostratified epithelium, it is very similar in function to the cylindrical one, with the difference that it gives a multilayered appearance, that is, its cells are stacked one from the other, giving the appearance of more than one epithelial layer as the stratified epithelium of our epithelial organ, but nevertheless it is not like that, there are many cells of irregular shape with a support in the basal one, that is why it is a single layer.
This last epithelium is also found in the airways in large numbers.
This could impact the population by gene flow that would increase between the two halves, and speciation would not occur.
<h3>What is Speciation?</h3>
Speciation may be defined as the process of formation of new species from a parental one. It occurs when members of similar populations no longer interbreed to produce fertile offspring within their natural environment.
The complete question is as follows:
- Traits that had developed through mutation would still exist in only one of the halves.
- Speciation would still occur because the two halves would be too different genetically to interbreed.
- The two halves would be reproductively isolated.
- Gene flow would increase between the two halves, and speciation would not occur.
Speciation requires time for genetic variations and mutations to occur. It makes the organism's reproductive isolated and hence the process of speciation may take place.
Therefore, the correct option for this question is D.
To learn more about Speciation, refer to the link:
brainly.com/question/2113835
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