The correct answer is climate. Many mass extinctions of life occurred due to major changes in climate. Climate change is as also known as global warming affects many things. It is causing the rising temperature of the Earth's surface due to human's abusive usage of things.
Vaccines help develop immunity by imitating an infection, but this “imitation” infection does not cause illness. It does, however, cause the immune system to develop the same response as it does to a real infection so the body can recognize and fight the vaccine-preventable disease in the future
Answer:
Option B. Viral genes may be encoded by DNA or RNA, but cellular genes are always encoded by DNA.
Explanation:
Virus is a unique organism having unique characteristics which act as both living and non living. In cell, it is living while outside the cell it is present in crystalline form. Virus is composed of two genome i. e. DNA or RNA. But cell is composed of only DNA genome. There is no nucleus present in virus. Mitochondria and ribosome are also absent.
Answer:
Hydrophillic head and a hydrophobic tail
Explanation:
Every fatty acid is composed of long chain of hydrocarbon tail. This hydrocarbon tail is nonpolar and insoluble in water. Hence this tail is labeled 'hydrophobic'.
However, the head of the fatty acid contains polar COOH group which is capable of interacting with water, hence the head is hydrophillic.
Hence, a fatty acid is composed of a hydrophillic head and a hydrophobic tail.
