The group in an experiment that all the conditions stay the same is the control group.
Answer: A. scalp hairs grow constantly throughout life.
Explanation:
Hair is a squamous keratinized epithelium which is consist of multi-layered flat cells. Hair are made up of protein called "keratin".
The statement "scalp hairs grow constantly throughout life" is false because at a particular age or due to several factors scalp hairs stop growing.
Scalp hair growth rate depends on three main factors including sex (female hair grows faster than male), age (hair growth slows with age), and ethnicity (Asian hair grows slower than Caucasian hair).
Scalp hair growth stops because of follicle devitalization when the hair length become two or three feet.
Hence, the correct answer is A. "scalp hairs grow constantly throughout life".
A. Neuron
The neurons are cells that process and transmits information through electrical and chemical signals.
-Sasha
Microevolution is small genetic changes within a specific population or a group within a population, occurring within a short time span, like one generation. Macroevolution is big changes across species and over long spans of time.
