Answer:
The number of habitats falls below a critical level.
Explanation:
The possible reason for extinction is that the number of habitats falls below a critical level. This makes it impossible for organisms to survive.
- A habitat is the dwelling place of living organism in an ecosystem.
- The resources and other materials that ensures the survival of an organism are made available in the habitat.
- When a habitat begins to thin out and can no longer support organisms, then extinction will ensue.
I think the correct answer from the choices listed above is option B. Keratin is the protein in mammals which shows only a primary and secondary structure. Keratin is a fibrous protein forming the structural constituent of hair, feathers, hoofs, claws and many others.
Answer:
Explanation:Nitrogen is a naturally occurring element that is essential for growth and reproduction in both plants and animals. It is found in amino acids that make up proteins, in nucleic acids, that comprise the hereditary material and life's blueprint for all cells, and in many other organic and inorganic compounds.
