Answer: Valves in the veins
Explanation: The flow of the blood inside the body takes place through the veins and arteries. The oxygenated blood from the heart is supplied to the different parts of the body.
The blood flows from the capillaries to the venules and from there to the veins. The blood moves in the veins by the rhythmic movement of the smooth muscles in the body.
Most of the blood moves against the gravity so there is a chance that it can backflow so to prevent this there are valves in the veins known as one way valves.
Answer: According to sources, the most probable answer to this query is that evolution happens because when life came it sought for survival. Now, this is through mutation which causes random DNA sequences leading to genotypic and phenotypic changes. Natural selection as relation to adapting to the selection forces of the environment. And when these factors is added by the niche and other large case scenario to cause major anatomical changes, speciation comes through. And that, the process of evolution. And how it is a mechanism and an intermediate interaction with the environment.
Explanation:
RNA is a copy of DNA that is used to make proteins. We usually compare all eukaryotic cells as a group to all prokaryotic cells.
