The challenges that scientists who want to study particular genes face are as follows:
1. There are many genes on a typical chromosome - A chromosome<span> typically contains hundreds to thousands of </span><span>genes.
2. </span>A small fraction of each chromosome encodes genes - <span> Genes only make up a small percentage of the genome; the rest is composed of non-coding sequences.
3. </span>It is difficult to distinguish between genes and non-coding genetic information - discriminating between<span> coding and </span>noncoding<span> regions in a given nonannotated genomic sequence is quite difficult.</span>
Answer:
B
Explanation:
Chlorophyll absorbs all spectrum of light but reflects green. That's why we see that leaves are green in colour.
Answer:
If an individual Drosophila has two or more populations of cells comprising different genotypes from one single egg then it is termed as twin spots or mosaic.
Explanation:
There might be different reasons for mosaic to occur like
Nondisjunctioning of the chromosomes
Lag in anaphase
Endoreplication
Mutations in a single cell
Mitotic recombination:
One of the major ways through which mosaic or twin spots arise is the mitotic recombination. It is also termed as somatic cross over. Twin spot or mosaic generally occurs if there is linking of heterozygous genes in repulsion. The recombination generally happens among the centromeres from the adjacent genes.
A common example of the mitotic recombination is the Bloom's syndrome. Bloom's syndrome is caused due to the mutation that occurs in the <em>blm</em> gene. As a result, there are defects in the BLM protein produced.
