Answer:
So that in a guinea pig cross in the offspring the recessive trait —long hair— can be observed in 25%, the most probable genotype of the parents is heterozygous Ss.
Explanation:
In guinea pigs, for the characteristic<u> hair length, short hair is the dominant allele and long hair is the recessive one</u>.
In order for 25% of the offspring to express the recessive characteristic, the parents must have a recessive genotype, which can be seen in Punnett's Square:
P: <u>Ss X Ss
</u>
<em>Alleles S s
</em>
<em>S SS Ss
</em>
<em>s Ss ss
</em>
Where the offspring is:
- <em>50% Ss with short hair phenotype
</em>
- <em>25% SS with short hair phenotype
</em>
- <em>25% ss whose phenotype would be long hair.
</em>
According to this, heterozygous parents for the characteristic long hair in guinea pigs have a 25% chance of having offspring with long hair.
The structure and shape of each type of human cell depends on what function it will perform in the body. For example, red blood cells (RBCs) are very small, flat discs, which allows them to easily fit through narrow capillaries and around sharp corners in the circulatory system to deliver oxygen throughout the body.
The elongated shape of muscle cells allows the contraction proteins to line up in an overlapping pattern that makes muscle flexing possible.
And human sperm cells’ structures allow them to “swim” long distances to reach an egg for fertilization
Chesapeake bay is an area that has suffered from overharvesting and eutrophication. Eutrophication is an enrichment of water by nutrients salts that causes structural changes in the ecosystem such as increased formation of algae and aquatic plants, depletion of fish species among other effects. The greatest source of nitrogen and phosphorus in a Chesapeake bay is agriculture
Answer:
Of course, you could scan their driver’s license or look for signs of facial wrinkles and gray hair. But, as researchers just found in a new study, you also could get pretty close to the answer by doing a blood test.
Woman looking at herself in mirror That may seem surprising. But in a recent study in Nature Medicine, an NIH-funded research team was able to gauge a person’s age quite reliably by analyzing a blood sample for levels of a few hundred proteins. The results offer important new insights into what happens as we age.
Explanation:
For example, the team suggests that the biological aging process isn’t steady and appears to accelerate periodically — with the greatest bursts coming, on average, around ages 34, 60, and 78
The right answer is D (less responsive to antigens)
It is proven that, after puberty, thymus activity (an organ that is included in the lymphatic system, producing T cells that pick up antigens) decreases and that in adult and aged people the thymus has no role. Work done in humans indicate that in fact the cellularity begins to decline from birth in favor of lymphocyte perivascular spaces and connective and adipose tissue, which leads to a decrease in the capture of antigens.
