Everything in Earth's system can be placed into one of four major subsystems: land, water, living things, or air. These four subsystems are called “spheres.” Specifically, they are the lithosphere (land), hydrosphere (water), biosphere (living things), and atmosphere (air)...
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One of them is definitely hun
Answer:
D. 1 BB : 2 Bb : 1 bb
Explanation:
This question involves a single gene coding for fur color in guinea pig. Black fur (B) is dominant over white fur (b). This means that, as stated in the question, if a black fur parent (BB) is crossed with a white fur parent (bb), a 100% heterozygous offspring (Bb) with black fur will result.
If two heterozygous guinea pigs are crossed i.e. Bb × Bb, the following gametes will be produced by each heterozygous parent:
Bb = B and b
Using these gametes in a punnet square (see attached image), offsprings with the following genotypic ratio will be produced:
1 BB : 2 Bb : 1 bb
BB and Bb = black fur guinea pigs
bb = white fur guinea pigs
Why did the narrator use the phrase “fit together like puzzle pieces” to describe how the cells of a developing human embryo form a human face