Which mode of inheritance produces heterozygotes with phenotypes that differ from either homozygote but typically more closely resembles one homozygous phenotype than the other?"
A) complete dominance
B) incomplete dominance
C) codominance
D) epistasis
E) incomplete penetrance
Answer:
B) incomplete dominance
Explanation:
Incomplete dominance occurs when the dominant allele of a gene is not able to mask the expression of the recessive allele completely. This results in the expression of a phenotype in the heterozygous genotypes that differ from both homozygous genotypes. However, the phenotype of the heterozygote is closer to one of the homozygous genotypes.
For example, the petal color in four o'clock plant is controlled by a gene with two alleles R and r. Here, the "R" allele can not produce enough pigment in heterozygous conditions to completely mask the expression of the "r" allele and the phenotype of the "Rr" plant is "pink". On the other hand, the phenotype of "RR" plant is red while that of the "rr" plant is "white".
<span>The role of the pollen is for the sperm to reach the egg. In the process of transportation, a lot of pollen grains can get lost and therefore there is greater need for it to be more than the ovules, since the eggs do not have to be transported anywhere. </span>
Answer: Convergent Boundary
Explanation:
A convergent boundary is an area on Earth where two or more lithospheric plates collide. One plate eventually slides beneath the other causing a process known as subduction. ... Convergent boundaries occur between oceanic-oceanic lithosphere, oceanic-continental lithosphere, and continental-continental lithosphere.
Answer:
- Only fMet-tRNA(fMet) can bind first to the P site in the ribosome. ( A )
- There are more than one tRNA with the 5' CAU 3' anticodon. ( B )
- The N-formyl group attached to methionine prevents fMet from entering interior positions in a polypeptide. ( D )
Explanation:
The statements that explains how N--formyl methionine (fMet) is only associated with the 5' AUG initiation codon and not with internal AUG codons, given that methionine in both cases in encoded by an AUG in the mRNA are :
Only fMet-tRNA(fMet) can bind first to the P site in the ribosome. ( A )
There are more than one tRNA with the 5' CAU 3' anticodon. ( B )
The N-formyl group attached to methionine prevents fMet from entering interior positions in a polypeptide. ( D )
While statement C is wrong.
Answer:
c. dendritic cells
Explanation:
An antigen presenting cell like dendritic cell is a part of adaptive immune system. When it encounters a harmful foreign antigen, it engulfs it via phagocytosis. The phagocytic vesicle fuses with the intracellular lysosome and here the antigen is broken into smaller fragments. With the help of MHC complex, these fragments are presented on the surface of dendritic cell hence it becomes an antigen presenting cell. This cell is then recognized by other cells of immune system like lymphocytes and destroyed.
Dendritic cells are present in skin and lining of lungs, nose, stomach, intestines. In skin they are called as Langerhans cells. Macrophages are another type of antigen presenting cells.