Answer:
Postzygotic isolating mechanism
Explanation:
Reproductive isolation can occur due to prezygotic or postzygotic isolating mechanism. Prezygotic mechanism prevents fertilization of gametes and can occur due to different mating behavior, different mating time period etc. Postzygotic mechanism occurs after the formation of zygote i.e. the organisms are able to mate and fertilization also occurs. However the resultant zygote may not survive. It might not survive immediately or might die before reaching the reproductive maturity. Such a situation would still come under reproductive isolation because the resultant offspring is not viable and not able to pass on the genes to the next generation.
Answer:
The base, it is called a nitrogen base
Explanation:
The cell membrane is surrounded partially or totally by the Endoplasmic Reticulum which are membranes that extend along the nuclear membrane.
