Answer:
A.
Explanation:
All other options are simply situational, while cold periods are usually seasonal.
Answer:
The mentioned characteristics of variability are witnessed because of the phenomenon known as X chromosome inactivation in heterozygous females. As females possess two X chromosomes, they actually should not possess any color blindness.
The phenomenon of X-chromosome inactivation takes place in a random manner at the time of embryo development. During this only one X chromosome is inactivated. If the chromosome comprising the defective gene is inactivated, the individual will possess normal vision.
If the chromosome comprising the usual gene gets inactivated than the individual will be color blind. In the given case of female, X inactivation took place in one eye. The inactivation of normal alleles has taken place and thus she possesses normal vision with one eye and is color blind in the other eye.
The three phases of signal transduction is (1) reception, (2) transduction, and (3) response. Reception involves the binding of a ligand, may it be a hormone or a neurotransmitter; to a receptor, may it be a membrane receptor, cytosolic receptor, or a nuclear receptor. After binding of the ligand to the receptor, there will be signal transduction of events that will ultimately form a response. For instance, insulin actin on the insulin receptor will trigger a series of events that will increase the transcription of the gene translating for glucose transporters and ultimately, increase the number of glucose transporters embedded in the cell membrane leading to increased glucose uptake in tissues.
