A single genetic locus that controls more than one trait is said to be _________

A geneticist crossed pure breeding black mice with pure breeding brown mice. All the 992 mice in F1 generation had black coats.

MaRussiya [10]

Answer:

The statements that apply are the third and the fourth.

Explanation:

Since the mice crossed were pure breeding, each parent produced sperms of one kind, both alleles of each parente were equal. Thus, the first (A) and second (B) statements are false.

Assume pure breeding black mice produced BB sperm and pure breeding brown mice produced bb sperm.

The punnett square for the first generation, F₁ is would be:

b b

B Bb Bb

This is, all the F₁ generation mice are Bb.

All the 992 in F₁ generation had black coats means black is dominant.

Now when F₁ generation is crossed, the punnet square reveals the second generation, F₂:

B b

B BB Bb

b bB bb

The brown allele that was hidden now appears.

Based on the assumption that black is dominant, BB, Bb and bB are black, which is 3/4 or 75%. This, is 75% of the mice in the F₂ genrertion are black.

The combination bb is brown. Thus, 1/4 or 25% of the mice in the F₂ generation are brown.

When the mice in the first generation were crossed, they yielded 961 black coated mice and 317 brown coated mice. That is:

Total mice: 961 + 317 = 1278

Proportion of black mice: 961 / 1278 ≈ 0.75 = 3/4

Proportion of brown mice: 317 / 1278 ≈ 0.25 = 1/4

Ratio black to brown: 3 to 1.

Therefore, it is proven that an approximately three-to-one ratio of black to brown cated mice in F₂ is accounted fro the black allele being dominant over the brown allele (choice C.)

Also, the brown allele is not independent from the black allele and dissapears in the F₁ generation: it is not independent because it presence will only be shown when the black allele is not present, and it is said that it dissapears because it is not revealed, it is hidden.

8 0

1 year ago

Assume you are investigating the inheritance of stem length in pea plants. You cross-pollinate a short-stemmed plant with a long

beks73 [17]

Answer:

75% would have long stems and 25% would have short stems.

Explanation:

7 0

2 years ago

Water Cycle 1. How is water stored on Earth during the water cycle? 2. Water moves into the atmosphere through ____________ and

Naily [24]

Water Cycle:

1. It is stored in the ground.

2. Evaporation, transportation, precipitation

3. Runoff comes straight from precipitation. Infiltration is from the ground while run off never went in the ground.

4. It will usually end up in the same place, the ocean

5. Water levels rise, temperatures rise, CO2 in atmosphere increases

Carbon Cycle:

1. Carbon is important because it is one of the basic building blocks of life.

2. Trees, animals, grass, decomposition, combustion, fossil fuels

3. Carbon enters as photosynthesis.

4. Carbon enters water to the soil decomposition. Aquatic plants have plenty of water to work with, so their main challenge is getting enough sunlight and air.

6. By breathing in the oxygen from plants.

7. Two ways carbon return from animals into water is through cellular respiration and decomposition.

8. Combustion is when we dig up the fossil fuel and burn it, then what is left goes into the air starting the cycle again.

9. Deforestation reduces the capacity of forests to be carbon sinks.

Nitrogen Cycle:

1. Nitrogen is important because it helps us grow crops, and it produces grass for animal.

2. It comes from lightning and is named nitrogen fixation.

3. Ammonification and then transitions into nitrification and then to assimilation.

Phosphorus Cycle:

1. It forms part of life sustaining molecules like DNA and RNA.

2. Phosphorus is never found in the atmosphere.

8 0

2 years ago

Explain by a series of statements or steps how a tree trunk gets wider.

Alex73 [517]

Answer:

A tree will get wider by the secondary growth of the cells. This happens when the cell growth of the cambia or lateral meristems causes them to elongate and become primary tissue.

The site below gives a detailed description of secondary growth.

https://www.arborday.org/trees/RingsTreeNatomy.cfm

6 0

2 years ago

What is a series of steps designed to help you solve problems and answer questions

Ksenya-84 [330]

A series of steps designed to solve problems and answer questions is "a scientific method".

6 0

2 years ago

A single genetic locus that controls more than one trait is said to be __________.