Answer:
Option A, keystone species
Explanation:
Keystone species are responsible for controlling any species from becoming dominant over all other species. The keystone species are found at the top of all the energy pyramids and food chains.
They control the explosion of population of prey and hence regulate the overall ecological diversity.
Some common example of keystone species is as follows –
Bison, prairie dog, large mammalian predators,
Hence, option A is correct
Composed of a phospholipid bilayer.
Hydrophilic heads and lipophilic tails on the phospholipids.
Follow this link for helpful answer
https://www.reference.com/science/function-gastric-caeca-7b6d7732ca4340e5
Answer:
Stem cell is taken either from bone marrow or from the blood directly
Explanation:
Stem cells are derived from two locations primarily a) Bone Marrow and b) Blood
The first step in this process is to remove the stem cell from its parent location and it is done in the following ways –
A) For deriving stem cell from blood – A drug with growth factor s is injected. Here no anesthesia is given to the patient. The growth factors leads to the movement of stem cells from bone marrow into the bloods. Blood with stem cells is taken out from the veins and filtered through the apheresis machine.
B) From Bone marrow – Bone marrow is removed from the pelvic bone through a needle and prepared for transplantation.
