why the frequency of sickle cell trait is so much higher in sub-Saharan Africa than in most other parts of the world?

The angle of Earth's tilt has changed throughout Earth's history and is still changing today. If Earth's tilt were to decrease

olganol [36]

Answer:

The world climate would drastically change.

Explanation:

First off, both poles would have rapid expansion, with the freezing of more water near the poles.
Many species of trees and plants would die out in certain areas, since they tend to be in their ideal locations, so the change in climate will make the northern parts of many habitats destroyed.
Deserts would expand and the average temperature would rise.
Also, many animals would also die out, because of the change in their environments.
Conifers would shift southward, causing many forests / parts of forests to turn into wastelands, causing the earth's oxygen production to decrease.

8 0

2 years ago

Which organ in the integumentary system keeps germs from entering your body?

Andrew [12]

Answer: The main organ of the integumentary system is the skin.

Explanation: The skin regulates body temperature, keeps germs from entering your body, and produces vitamin D to help absorb calcium.

6 0

3 years ago

In a unique species of plants, flowers may be yellow, blue, red, or mauve. All colors may be true-breeding. If plants with blue

Zolol [24]

Answer:

F1) 100% bbRr, red flowered plants.

Explanation:

<u>Available data:</u>

flowers may be yellow, blue, red, or mauve
colors may be true-breeding
the cross of blue-flowered plants with red-flowered plants, produce plants that have yellow flowers
F2 generation: 9/16 yellow, 3/16 blue, 3/16 red, and 1/16 mauve.

Knowing that the phenotypic ratio is 9:3:3:1, we can assume that there are two genes involved in the flower color expression. We can name these genes B and R with a dominant and a recessive allele each (B, b and R, r respectively).

According to the first cross, we might establish the following genotypes:

1st Cross: blue-flowered plant x red-flowered plant

Parentals) BBrr x bbRR

Gametes) Br, Br, Br, Br bR, bR, bR, bR

F1) 100% BbRr, yellow plants

Parentals) BbRr x BbRr

Gametes) BR, Br, bR, br

BR, Br, bR, br

Punnett square) BR Br bR br

BR BBRR BBRr BbRR BbRr

Br BBRr BBrr BbRr Bbrr

bR BbRR BbRr bbRR bbRr

br BbRr Bbrr bbRr bbrr

F2) 9/16 yellow ---> 1/16 BBRR + 2/16 BBRr + 4/16 BbRr + 2/16 BbRR

3/16 blue ------> 1/16 BBrr + 2/16 Bbrr

3/16 red---------> 1/16 bbRR + 2/16 bbRr

1/16 mauve ----> 1/16 bbrr

So,

Yellow-flowered plants: BBRR, BBRr, BbRR, BbRr
Red-flowered plants: bbRR, bbRr
Blue-flowered plants: BBrr, Bbrr
Mauve-flowered plants: bbrr

According to these genotypes, the second cross would be like following,

2nd Cross: true-breeding red-flowered plants with true-breeding mauve flowered plants.

Parentals) bbRR x bbrr

Phenotype) Red Mauve

Gametes) bR, bR, bR, bR br, br, br, br

Punnett square) bR bR bR bR

br bbRr bbRr bbRr bbRr

F1) 100% bbRr, red flowered plants.

6 0

3 years ago

Please help !! I don’t know the answer !!

just olya [345]

Answer:

I am pretty sure it is A or D sorry if this does not help

8 0

2 years ago

If you can help me thank you

Ivan

Answer:

quantitative

Explanation:

because it discuses the number of the petals

4 0

2 years ago