Answer:
Mark pathogenic cells for destruction. (Ans. B)
Explanation:
Antibodies are generated by the plasma cells, and once these secreted, they attach quickly to the surface of the toxin and stop the toxin from infecting the normal body cell by blocking key extracellular sites.
Antibodies also help to mark pathogens for destruction by the help of macrophages or neutrophils and they are known as phagocytic cells because they are highly excited to macro-molecules complexed with antibodies.
Answer:
b. 2N meiosis 1N fertilization 2N
Explanation:
In eukaryotic organisms, gamete mother cells are diploid (2N) and have two complete sets of chromosomes. Meiosis in male and female gamete mother cells form haploid male and female gametes (N) respectively. This occurs since meiosis reduces the number of the chromosome to half in the daughter cells. The fusion of haploid male and female gametes during fertilization restores the diploid chromosome number of the species and forms diploid zygote (2N). Repeated mitotic divisions in the diploid zygote form the diploid organism.
a chemical substance produced and released into the environment by an animal, especially a mammal or an insect, affecting the behavior or physiology of others of its species.