Answer:
The cells on the cornea are maintained by pheripheral vessels and surrounding fluids.
Explanation:
*- The capillaries of the limbus nourish the peripheral part of the cornea.
*- Tears supply of glucose in the tear film
*- Aqueous humor nourishing the outermost layers of the cornea the endothelium being a unicellular layer
Answer:
A. I, II, III, and V only
Explanation:
In genetics, an allele refers to the specific form of a gene, which encodes traits. These alleles are usually in pairs in a diploid organism i.e. an organism with two sets of chromosomes. According to Gregor Mendel,
- An allele can either be DOMINANT when the allele masks the phenotypic expression of its allelic pair while the allele that is masked is said to be RECESSIVE.
- Two alleles can also be CO-DOMINANT when the two alleles are neither dominant or recessive over one another but are simultaneously expressed in that particular gene.
- Alleles can also be INCOMPLETELY DOMINANT when one allele is not completely dominant over the other, hence, forms a third intermediate phenotype when in combination with the second allele i.e. in an heterozygous state.
Based on this, an allele can be dominant (I), recessive (II), codominant (III), and incompletely dominant (V).
Transduction. Transudction is the process where foreign DNA is introduced into a cell by a virus or viral vector. An example would be a viral transfer from one bacteria to another.
Answer:
The possible blood types of their children are: type AB (iAiB), type A (iAi), type B (iBi), type O (ii)
Explanation:
Blood type in humans is controlled by a gene with multiple alleles. Alleles iA and iB are dominant over allele i but co-dominant. The following blood types are encoded by the following alleles:
Blood type AB - iAiB
Blood type A - iAiA or iAi
Blood type B - iBiB or iBi
Blood type O - ii
According to this question, a man who has type B blood has children with a woman who has type A blood. They are both heterozygous, meaning that the man's genotype is "iBi" while the woman's genotype is "iAi". Both parents will produce gametes as follows:
iBi = iB and i
iAi = iA and I
Using these gametes in a punnet square (see attached image), the following possible blood types are produced in the offsprings:
- type AB (iAiB)
- type A (iAi)
- type B (iBi)
- type O (ii)