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.
<span>150-200 species of plant, insect, bird and mammal become extinct every 24 hours., according to the Scientist Estimate. </span>
The answer should be A capillaries
The answer is an envelope.
A virus is an infectious agent that can replicate only inside a host cell. When it is outside the cell, it consists of genetic material coated with protein capsid. Some viruses also have an envelope which covers capsid. The function of the envelope is to identify and bind some receptor sites on the host membranes. After fusing with the cell membrane, it allows to capsid and genetic material to enter the cell and infect it.
Answer: Single cell organisms dont need a respiratory system because oxygen and carbon-dioxe diffuses between their body tissues and the enviorment.
