Answer: Option B.
Neural crest and peripheral nervous system.
Explanation:
Neural crest are bilateral paired cells of the neural tube that arise from the ectoderm layer of the embryo. Thesescells move to different part of the body and differentiate into various cell types like melanocytes,cartilage and bone, smooth muscle, craniofacial, neurons, gangalia e.t.c. The neural crest running through neural tube develop into peripheral nervous system after birth. Peripheral nervous system consist of neurons and gangalia outside the nervous system The peripheral nervous system connect the central nervous system to organs, skin and limbs.
Answer;
A bottleneck effect
Explanation;
When only a few individuals survive unfavorable times, thereby losing the majority of genotypes in the next generation, it is called a bottleneck effect.
It occurs when there is a disaster of some sort that reduces a population to a small handful, which rarely represents the actual genetic makeup of the initial population.
Answer:
I believe it's the <em>collecting</em><em> </em><em>duct</em>
Volumes.
If you put equivalent volumes in a bag, where both weigh the same, the density might get equal.
Hope it helped,
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