Expert: Walter Hintz - 9/15/2005

Question
I need your help on some problems all you have to do is answer the question in compltete sentences.

1. Why must all amphibians spend at least part of their lives in water?

2. Lizards often lie in the sun in the morning. Why?

3. Basking sharks swim close to the surface of the water and appear to be sunning themselves like lizards. In fact, however they are feeding on plankton. Why might a land dwelling creature like a lizard need to sun itself, while a water dwelling creature like a shark does not?

4. Some species of lungfish breathe only air; they have have no gills, and will drown if forced underwater. Why might it be an advantage for lungfish to breathe air even though they live in water?

5. Arthrpods and birds both molt. For which of these creatures is molting most dangerous? Briefly explain your answer by compariing the two molting processes.

6. Cats raised by their mothers hunt small rodents, insects, and other creatures. Cats raised in isolation from other cats generally do not hunt these things. Do you think hunting in cats is learned or instinctual? Why?  

Answer
Hi jamie
1. Amphibians have a very thin skin and would dry out if not in the water most of the time and they aslo take in oxygen through the skin.

2.Lizards derive heat from the sun that was lost ivernight.

3.Temperature variations on land are much greater than in the water.

4.LUngfish are found in areas that sometimes dry out and they then need to breath air.

5.Birds molt over long periods of time and there is always body covering while arthropods lose the exoskeleton all at once leaving them vulnerable.

6.This very fact shows that although hunting is instinctual in cats it is reinforced by learning from the mother.