They consist of identical sister chromatids
I'm not sure about the first two but I think the one about the halite crystal is cubic. :)
The cell membrane is said to be selectively permeable is because it allows a select few things to go through while stopping the passage of other stuff.
Answer:
Internal Fertilization: Mammals,birds and reptiles in them the mode of fertilization is internal
External Fertilization: Amphibians and fishes used external fertilization.
Egg laying Animals;Birds,reptiles and some mammals platypus lays eggs.
Explanation:
Fertilization is a process in which a female egg (Ovum) and male egg (sperm) unite to form a zygote.A zygote is a fertilized egg which grows within an embryo.The process of fertilization is important in eukaryotes such as animals, humans,birds and plants. Fertilization divides a cell into many daughter cells by the process of mitosis and meiosis.It doubles the chromosome numbers.Fertilization are of two types internal and external.
