Heterozygous refers to a pair of alleles in which one is dominant and one is recessive. As you can see, all genotypes for possible offspring in the Punnett square are heterozygous. This means the probability of the parents having a child that is heterozygous is 100 percent likely.
Answer:
<span>D. 100%
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Answer:
Answer is A. Vicariance does not require organisms to disperse.
Explanation:
Vicariance occurs when there is a sudden occurrence barrier , such as geographical area barrier that cause the isolation of species of organisms.
Dispersal involves the movement of the organism while vicariance is the change in environment due to sudden occurrence in the area.
In this case, vicariance does not involve movement of organisms while dispersal involves movement of organisms.
The myelin sheath is the protective layer, which is present in the outer layer of the neural cells. This myelin sheath prevents the loss of electrical impulses, which are being conducted in the neurons. This also act as an insulator between neuron and its external environment.
This layer is mainly made up of the protein and fatty substance. The degeneration of the myelin sheath result in many neurological disorders.
Hence, the correct answer is myelin sheath.
The answer is D) 1/2.
Let's imagine that two genes of the genotype can be analysed separately.
Black fur is determined by dominant allele B. In this case, parents Bb and BB will give offspring with only brown fur:
Parents: Bb x BB
Offspring: BB BB Bb Bb
Both homozygous (BB) and heterozygous (Bb) offspring will have black fur.
On the other hand, long tails are determined by recessive allele t. Parents Tt and tt will have 50% offspring with short tail and 50% offspring with long tail:
Parents: Tt x tt
Offspring: Tt Tt tt tt
Heterozygous offspring (Tt) will have short tail, and homozygous offspring (tt) will have a long tail.
So, the offspring will definitely have black fur and will not affect the fraction of the offspring with black fur and long tails from the cross of <span>BbTt × BBtt. But, </span>there will be 2 out of 4 offspring with short tails which is 50% or 1/2.
Answer: Option C
Explanation:
These cells are soft because of its function. Gaseous exchange takes place by the help of these cells. Spongy mesophyll cells are covered by thin layer of water and are loosely packed.
This is because, during the day time when the plant is performing photosynthesis these cells allows the carbon dioxide into the mesophyll cells and the oxygen out of the plant body.
