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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Answer:
if im correct its a conductor
Explanation:
A material that allows an electric charge to pass through it easily is called a Metals such as iron, steel, copper, and aluminum are good conductors.
<span>3. Reduced bone marrow in the spongy bone.</span>
Answer:
The plants have the higher population density. This is because, when compared with that of the insects, the number of plant species per acre area is higher; 2800 compared to 683.3
Explanation:
The number of individual species per unit area of land is known as the population density. Population density describes how crowded or spaced out a given species is in a particular area. The higher the population density, the more crowded the species are and vice versa. The formula for calculating population density is given as:
Population density = Number of species/land area
Population density of the insects = 820/1.2 = 683.3 insects/acre
Population density of the plants = 560/0.2 = 2800 plants/acre
Therefore, the plants have the higher population density.
This is because, when compared with that of the insects, the number of plant species per acre area is higher.
