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
.
Answer:
<em>Competition without division of resources may lead to extinction.</em>
Explanation:
Some species are better adapted to live in an environment as compared to other species. If resources become scarce then the species with better traits might take up all the resources of a species which are not better adapted. This will cause the species with unfavourable traits to become extinct. To survive in an environment, an organism needs to change and adapt according to the conditions of the environment. Otherwise, the species will become extinct.
Answer:
1. Cell
2. cell theory
3. Organismal theory
4. resolving power
Explanation:
The cell is the smallest known unit of all living organisms. They are called the building blocks of life. An organism can be unicellular (made up of one cell) or multi-cellular (made up of many cells).
2. Cell theory was formulated and developed by Schleiden, Schwann, and Virchow. They are considered as the basic principles of biology.
It states:
1. Living organisms are made up of cells.
2. Cells are the basic unit of life.
3. Cells are formed from pre-existing cells.
4. Energy flows inside the cell.
5. DNA is passed on from cell to cell.
6. All cells have the same basic chemical composition.
3. Organismal theory is the intended counter-argument of the cell theory. It was developed by Reichert, Strasberger, Sherrington, and Pavlov. It argues that the basic unit of life is the organism itself, suggesting that an organism came about from a cell that expanded.
4. Resolving power is the ability of an optical instrument like a microscope or a telescope to view objects that are close together as separate, abling the viewer to distinguish the two from each other.
The answer i think it changes
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