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:
<u>Some overall examples of biotic and abiotic factors are listed below.</u>
<u>Biotic factors: predators, competitors for food, competitors for space, parasitism, disease, animals, plants.</u>
<u>Abiotic factors: sunlight, wind, soil, atmosphere, water, temperature, humidity, UV radiation, salinity, pH levels.</u>
Meiosis I produces 2 haploid cells and meiosis II produces four haploid cells.
Answer:
Action potential.
Explanation:
Action potential may be defined as the change of the membrane potential of the cell with response to the stimulus. The different ions enter and exit the cells.
Action potential generates in the cell when the threshold voltage - gated channel reaches and opens the voltage gate channel. The opening of voltage gated channel changes the membrane potential of the cell.
Thus, the correct answer is option (4).
Glucose which is stored in the muscles, livers and some of the fatty areas in the body, can be transformed into Glycogen for future use. SO, the answer is C.