Answer:
The cross that guarantees a height trait ratio in the offspring of 1 : 1 high/low is Hh X hh (option C).
Explanation:
For a characteristic such as size, where tall (H) is the dominant trait and short (h) is the recessive, the crossing of a tall heterozygous (Hh) individual with a short one will have a probability that half of the offspring will be tall and the other half short.
This can be demonstrated with a Punnett square:
Cross Hh X hh
Alleles H h
h Hh hh
h Hh hh
Based on this result, half of the offspring will be tall, with genotype Hh, and the other half short, with genotype hh, which corresponds to a tall : short ratio of 1 : 1.
In the other options is not possible to obtain this result:
<em>A) HH Xhh = 100% Hh.</em>
<em>B) hh X hh = 100% hh.</em>
<em>D) Hh X Hh = 50% Hh, 25% HH and 25% hh.</em>
Are you in 7th grade ?? I remember doing this but all the answers were in the book. Did you not being your book home??
Answer:
directional selection
Explanation:
Directional selection is the most common type of natural selection and occurs when some individuals with characteristics favorable to the conditions of the environment in which they live, have survival advantages over individuals who do not have this advantage, who end up dying.
Imagine, for example, a graph showing the directional selection in the same species of moths. Moths of the same species have white and brown collations, in summer, brown moths can camouflage themselves on tree trunks, while white moths cannot and are easily captured by their predators, which means that the amount of white moths decrease. In this graph, the population of white moths would be at a minimum, at the same time that the population of brown moths would be at maximum.
However, with the arrival of the reverse, snow begins to cover the trees, allowing white moths to camouflage themselves more easily. The brown moths, then, are very exposed to predators, causing their population to reach the minimum while the population of white moths reaches the maximum.
Are you looking for projects like experiments?
Answer:
A. Integumentary system
Explanation:
The integumentary system consists of the skin,hair and nail. This system consists of the largest organ in the body. The skin helps in protection against pathogens by shielding the internal body system from external objects.
The skin also helps in Vitamin D production through sunlight.
It also helps to prevent dehydration through regulation of water loss.
