The cell wall protects a plant cell by giving it protection and support.
The cell wall is made of cellulose which is a specialized sugar that helps give the wall structure and support to protect the inner part of the cell.
Selective permeability is the cell wall being particular about what they let in and out of the cell. It is important because if the cell just let any old molecule inside, it would be letting potentially harmful things in.
<span>A property of t cells, but not b cells, is their </span>ability to form cells that directly kill virus-infected host cells.
There are four nitrogenous bases<span> found in </span>DNA<span> that are called guanine, adenine, thymine and cytosine.</span>They<span> are abbreviated by the first letter in their name, or G, A, T and C. The </span>bases<span> can be divided into two categories: Thymine and cytosine are called pyrimidines, and adenine and guanine are called purines.</span>
Answer:
d. Expressivity refers to the range of expression of a given phenotype.
e. Penetrance refers to the percentage of individuals that expresses the mutant phenotype.
Explanation:
Penetrance is the probability of a gene being expressed. Sometimes, phenotype is not observed even when the dominant allele is present. It is a result of various genetic and environmental factors coming together.This phenomenon is called as incomplete or reduced penetrance. For example: polydactyly trait is produced by a dominant allele but its penetrance is low in general population hence few people show this trait.
Expressivity is the variation in phenotypic expression when an allele is penetrant. Same genetic combination for a trait can have different expressivity in the same population. This phenomenon is also a result of genetic and environmental factors acting together. For example: people who do end up showing polydactyly trait may show it to different degrees. Some might have one extra finger, some might have two. Some might have a stub, some might have a full grown finger.