<span>Diffusion and osmosis are important to cells because they don't require energy to transport very important molecules such as water and steroids.</span>
Option D – amphibians may use their skin for gas exchange is the characteristic feature of amphibians that differs from reptiles.
Explanation:
The amphibian skin is moist, thin and marbled and supplied by blood vessels running on its surface. The moisture present in the skin dissolves the oxygen present in its surrounding which is absorbed by the blood vessels. Special glands help the amphibians to keep the skin moist.
The very thick and tough scales present on the reptiles prevent them to absorb oxygen through their skin. Hence, they breathe and respire through their lungs.
Amphibians have three-chambered heart. They do not develop amniotic eggs. Adult amphibians although spend much time on land, they breed only in water due to the absence of amniotic sac
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Is the answer three
Because they help the body absorb vitamins a, d, e, and k.
<span>When practicing birth control as natural family planning, it is not true that it is almost 100 percent effective. Birth control as natural family planning does require careful tracking of the menstrual cycle, demands focus on bodily changes, and does require women from having sex on days ovulating and following. Even if sex is is had outside ovulating days, it is possible to get pregnant, thus it is not 100 percent effective.</span>