Answer:
The correct answer will be option-A
Explanation:
Chromosomal abnormalities are caused when the chromosome pair fails to disintegrate through a process called non-disjunction. The non-disjunction of chromosomes usually takes place at the anaphase I or II of meiosis I which involves the X and Y chromosomes.
The abnormality observed with 45 chromosomes or reduction in one sex chromosome or 45, XO is caused when one X copy of a chromosome is completely absent in the cell.
The cause for the loss of one chromosome is the non-disjunction during meiosis I.
Thus, option-A is the correct answer.
Answer:
B. Antibodies react specifically with an antigen.
Explanation:
Serological tests are blood tests that look for antibodies in your blood. They can involve a number of laboratory techniques. Flucculation tests are based on the precipitation that takes place when antibody and specially prepared antigens are mixed together
Answer:
1. Pollen tube
2. Style
3. Ovary
Explanation:
This process is describing the process of POLLINATION, which is the transfer of pollen grains from the anther of a male flower (androecium) to the stigma of the female flower (gymnoecium). After pollination i.e. the pollen has landed on the sticky stigma, the pollen grows out a tube called POLLEN TUBE.
The pollen tube extends through the STYLE of the female flower called PISTIL to the OVARY. The ovary is the reproductive part of the female flower that produces the ovules, which the sperm in the pollen is about to fertilize.
Answer:
C
Explanation:
Animals that don't adapt to their new environment die
