AnsweLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLlllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO
Explanation:
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.
Answer:
b, this is because a consumer, is something that consumes something, and the clam consumes the energy and nutrients when it filters the particles in from the water. Because it consumes these, it is a consumer for that reason. So, the answer is b. Hope this helps!!!
Answer:
A point mutation can be described as a mutation in which changes occur in a single nucleotide. A nucleotide may get changed, deleted or inserted from the sequence of DNA. Point mutations can be harmless or harmful depending on the nucleotide in which the changes occur.
A change in just one nucleotide can result in the formation of wrong amino acid and hence changed or wrong proteins can be formed. If the original protein was involved in cellular reproduction, then the entire process of reproduction can be affected by a point mutation.
Sickle- cell anaemia is a disease in which the body fails to produce enough healthy red blood cells. This disease occurs due to point mutation. Point mutation occurs where glutamine (GAG) of the β-globin gets changed into valine (GUG). This change causes the haemoglobin to get a deformed structure due to which it is not able to carry out oxygen.
