The soon to be male organism, developing from the zygote, receives or inherits the X chromosome from his mother. His father provides him the y chromosome, the smaller of the 2 sex chromosomes.
Answer: D. a genetic bottleneck
Explanation:
A genetic bottleneck also known as a population bottleneck is one that describes a sharp reduction in the size of a population caused by environmental events like in the above or caused by human activities.
Axons with large diameters conduct impulse faster than those with small diameters. Also Myelinated axons conduct impulse faster than unmyelinated axons. Axons with the largest diameter are all myelinated, therefore they are capable of salatory conduction (Impulses jump from one myelinated node to another). The smallest diameter axons are unmyelinated, so their conduction is continuous.
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