Question

1. Memory B cells

1. Prevent initial infection
2. Can be generated from immunization (vaccines)
3. Kills infected host cells
4. Undergo apoptosis soon after infection subside

2. Which of the following would be able to recognize the pathogenic bacterium E. coli strain H 10407 when it infects the body?

1. Phagocytes
2. B cells
3. T cells
4. All of the above

3. A zygote is formed

1. Just prior to fertilization
2. When more than one sperm fertilizes the same egg
3. Within the ectoderm of a blastula
4. When sperm and egg nuclei fuse

Answer 1

Ans1)B

Memory B cells are generated initially after the first infection so as to protect the body from the successive infections by the same pathogen .These memory cells can be produced by vaccination also.

Ans2)D,All of the above

All the cells that is the T cells,  the B cells and phagocytes are part of the innate immunity and recognise E. Coli infecting the body.

Ans3)D

Zygote is formed when the nuclei of the sperm and the egg fuse with each other.