D. controlled cell suicide
Answer:
Hypothesize that the ants are following a scent trail that the first ant left.
Hope it helps.
Answer: B-cells fight bacteria and viruses by making y-shaped proteins called antibodies, which are specific to each pathogen and are able to lock onto the surface of an invading cell and mark it for destruction by other immune cells. C-cells are a virus-bound antibody that binds to receptors, on the surface of phagocytic cells and triggers a mechanism known as phagocytosis, by which the cell engulfs and destroys the virus.
Explanation: sorry this answer was not simple at all -_-
Answer:
(A) The variation resulting from meiosis and the union of gametes means some individuals will have a chance of colonizing diverse distant environments successfully.
(D) Vegetative propagation is more efficient than sexual reproduction when the current generation is well adapted to the local environment.
Explanation:
Sexual or asexual (options B and C) are not a "last ditch", it pretty much depends on the type of organism and its strategy for survival. There are thousands of organisms that can reproduce either sexually or asexually depending on the environmental conditions.
Option A. Genetic variability is important because sometimes the genetic variability produce during the sexual reproduction processes (crossing over, chromosomes assortment and DNA from 2 parents) can confer an organism the adaptability mechanism to thrive in different environments.
Option D. Since asexual reproduction delivers genetical equal organisms, the offspring is already adapted to local conditions and can colonize at a faster rate.
