<span>Hay fever is a manifestation of allergic reaction
from pollen, which is prevalent during haying season. Hay fever is commonly
known as allergic rhinitis caused by an oversensitive immune system,
particularly the lymphocytes, leading to a misdirected immune response. The body
undergo a sensitization when one develops IgE antibodies and develop a strong
TH2 response against pollen. Then, this newly develop IgE antibodies sticks to
basophils and mast cells with no signs and symptoms yet. However, when one is
expose again to pollens, mast cells will be activated and release mediators who
are responsible for immediate vascular and smooth muscle reaction. After this, local
clinical manifestation of hay fever will be observed. </span>
Answer:
The genes are linked, and the arrangement is coupled (one homolog has both dominant alleles; the other homolog has both recessive alleles).
RY
/
ry
Explanation:
R_= colored aleurone
rr= colorless aeurone
Y_= green plant
yy= yellow plant
They do a testcross between a plant of unknown genotype and phenotype and a plant that is homozygous recessive for both traits (yr/yr) the following F1 is obtained:
- 88 Colored, green (RY/ry)
- 92 colorless, yellow (ry/ry)
- 8 colorless, green (rY/ry)
- 12 colored, yellow (Ry/ry)
If the genes assorted independently, all of the possible offspring phenotypes would appear in the same frequency. However, they obtained 2 phenotypes much more abundant that the other two. Since recombination is a rare event during crossing over, when two genes are linked the recombinant gametes are produced less frequently than the parentals.
We can propose that the phenotypes Colored, green (RY) and colorless yellow (ry) are the parental gametes, and the unknown plant has the arrangement RY/ry, with both genes linked.
Answer:
D. Meiosis forms four cells all with different genetic material
Explanation:
They are haploid cells and each cell only had one set of chromosomes. Meiosis results in variation.
The electrical property of the membrane changes. There is a small undershoot in the membrane potential.
It helps classify animals according to their needs.
Hope this helps!
-Payshence xoxo
