Answer;
A) Blood pressure decreases greatly; blood flow to the heart is inadequate, and blood pressure decreases.
Explanation;
-With negative feedback, the output reduces the original effect of the stimulus. While in a positive feedback system, the output enhances the original stimulus.
-Negative feedback is the most commonly used feedback loop in the body. Negative feedback is used to negate or counteract a stimulus without completely eradicating it.
-One key difference between the two feedback is that positive feedback loops are used to eradicate a stimulus. Another key difference is that responses through positive feedback become more amplified over time. So once a stimulus activates a positive feedback loop it is not turned off until the stimulus is completely removed.
Answer: Only some of the organisms survive and reproduce.
Natural selection is a process of differential survival and reproduction in which organisms bearing favorable phenotypic traits survive in changing environmental conditions. Therefore, only some of the organisms survive and reproduce which have suitable phenotypic trait. For example a population of beetle bearing two colors red and green. The green colored beetles mimic the color of grass will remain undetected by birds and those with red color easily observed and detected by birds. Hence, only green beetles are favored for survival over red beetles.
The answer is D.
Homo naledi seems most likely to be a member of the genus Homo; however, its small brain size is regarded as a primitive hominin trait more reminiscent of australopithecus.
Homo naledi is an extinct species of hominin, which anthropologists first described in September 2015 and have assigned to the genus Homo.
Answer:
The unit cell's edge length is 
Explanation:
Number of atom in BCC unit cell = Z = 2
Density of barium metal= 
Edge length of cubic unit cell= a = ?
Atomic mass of Ba(M) = 137.33 g/mol
Formula used :
where,
= density
Z = number of atom in unit cell
M = atomic mass
= Avogadro's number
a = edge length of unit cell
On substituting all the given values , we will get the value of 'a'.
The unit cell's edge length is
