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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Stone tools we’re first used around 3,300 BCE
Answer:
b. amount of energy available as fuel for the body
Answer:
1. At the end of S phase- 20 pg DNA
2. At the end of G2 phase- 20 Pg DNA
Explanation:
The cell before undergoing M phase undergoes the steps of interphase that is G₁, S and G₂ phase.
During S phase, the process of cell replication takes place which replicates the DNA as a result of which the amount of DNA doubles. This DNA amount is reduced to half during the anaphase stage of M phase.
In the question since the amount of DNA is 10pg therefore the amount will be double during S phase and becomes 20 pg and will remain 20 pg until the DNA is distributed therefore at the end of G₂ phase Will remain the 20 pg.
Answer:
adaption radiation, coevolution
Explanation:
