<span>Proliferation of lymphocytes occurs immediately after activation, as well as the encounter of antigen. First, these antigen are bound, after which activation begins. Activation immediately leads to proliferation, as well as differentiation. Proliferation is an increase in the number of something, in this case, in the number of lymphocytes, or white blood cells. </span>
The correct answer is option B
Sperm cells when pollinated by the insect to the female body part stay there for a while til the part of the flower determines its suitability and once it is done the sperm travels down through the pollen tube.
Answer:
Due to environmental conditions.
Explanation:
With the passage of time, environmental conditions change which causes the evolution of of four legged land animals from fish like creature. This change occurs due to change in environment. In water, there is no need for legs because fish moves with the help of fins and tail but the organisms that lives on land has legs in order to move from one place to another so we can say that change in the physical structure of organism occurs due to environment.
Answer:
the process by which green plants and some other organisms use sunlight to synthesize foods from carbon dioxide and water.
Explanation:
Answer:
Small external openings of lungs help in two ways:
1. It helps in trapping the dust and pathogens like bacteria, fungal spores et cetera. Larger opening would provide dust and pathogen a wider area to enter into the body.
2. The smaller opening prevents the drying of the respiratory membrane. A moist membrane is essential for the successful exchange of oxygen and carbon dioxide in the lungs.