Answer:
The return of blood to the heart is assisted by the action of the skeletal- muscle pump. As muscles move, they squeeze the veins running through them. Veins contain a series of one-way valves, and they are squeezed, blood is pushed through the valves, which then close to prevent backflow.
Because they supply much energy to the food by preparing their own food because the above one can't prepare it own their own
One long, single molecule of double stranded, helical, supercoiled DNA. In most bacteria, the two ends of the double-stranded DNA covalently bond together to form both a physical and genetic circle
Anaphylaxis,<span>serum sickness and toxicity from food are the three problems.
Anaphylaxis refers to a severe and very serious allergic reaction which should be treated right away otherwise it may caus death, Serum sickness is also similar to the allergy and in type II hypersensitivity and clinically we can say that the reaction due to the medicine that does not contain protein. Toxicity from food refers to the food poisoning that is caused by contaminated food.</span>