Question

What are two reasons early tetrapods AND modern amphibians must live near water? (select two) © Multiple answers: You can select more than one option O A adults have gills and must return to water frequently to do gas exchange B adults release eggs and sperm into water O C adults are aquatic O D gas exchange occurs across skin that must remain moist O E all adult amphibians have limbs that are like fins

Answer 1

Answer: B. Adults release eggs and sperm into water

D. Gas exchange occurs across skin that must remain moist

Amphibians are animals which can live in water and land. Their mode of fertilization is external (occurs outside the body) where the adult males release sperm into water and adult females release egg into water and the egg and the sperm fuse (fertilize) to form zygote. So amphibians depend on water for reproduction. Since they can exchange gas through skin, their skin loses moisture rapidly and hence should be near water to counter the moisture loss. Their young ones (larvae) have gills and needs to be in water for breathing. They also need to be near water for maintaining body temperature.