Answer:
c. bivalents.
Explanation:
In Meiosis a bivalents are formed during the first stage of meiosis which is the prophase. The bivalent consist of a paired chromosome and four chromatids i.e two chromosomes in a tetrad. one chromosome comes from each parent.
In mitosis, a bivalent is not formed. There is the presence of chromatids, homologs, centromeres and spindles during mitosis and meiosis.
The best answer is C
The process by which a cell divides is called mitosis. It results in two daughter cells that are genetically identical to each other and to the original cell.
Multicellular organisms, depend on mitosis for growth and repair. Organisms repair some of their tissues using mitosis to regenerate new cells. Not all cells undergo mitosis at the same rate. In man, brain cells are much more difficult to regenerate than cheek cells which are constantly being replaced.
Answer:
A plastic bag because the others would ruin the evidence the cotton would absorb the blood same with the envelope , paper bag.
Explanation:
Answer:
Option-D
Explanation:
In the given question the genotype of parental allele is- AbaB X AbaB. The alleles formed will be- AB, Ab,aB, ab in which the crossover allele will be AB and ab.
1. Unlinked genes
Now of these alleles are unlinked then the alleles will assort independently of each other therefore performing the punnett square we will get dihybrid ratio as 9:3:3:1 in which
1. A_B_ are 9
2. aaB_ are 3
3. A_bb are-3
4. aabb- 1
Since the crossover allele are AB and ab therefore A_B_ are 9 and aabb- 1 represent recombinant genotype.
2. Linked genes
When the genes will be linked then chances of crossing over will be reduced as a result of which only two type of allele will be formed which are- Ab and aB and the recombinant frequency will become less.
Crossing these allele will form Aabb
, AaBb
, AaBb and aaBB genotypes.
The recombinant ratio will decrease as A_B_ is 2 and aabb is not present.
Thus, option-4 which states that the unlinked ration is 9:3:3:1 and linked ratio is <9: >3: >3: <1 is correct.