Answer:
The correct answer will be option-D.
Explanation:
Calcium plays an important role in muscle contraction as they are released from the sarcoplasmic reticulum after they receive electric impulse.
Calcium triggers the muscle contraction cycle as these calcium ions bind to the troponin-tropomyosin complex. This binding exposes the myosin-binding site on the actin on which high energy myosin binds and cross-bridge is formed.
This cross-bridge formation causes the contraction of the sarcomere and therefore muscle contracts.
Thus, option-D is the correct answer.
MITOSIS is used to generate more cells. It is a kind of cell division that the new cells are identical.
Answer:
Oxidation of NADH by electron transport chain ensures a continuous supply of NAD+ for glycolysis.
Explanation:
To continue the process of glycolysis, cells must have a continuous supply of NAD+ which is required during one of the reactions of the payoff phase of glycolysis. Two molecules of NADH are formed per glucose molecule during glycolysis. The NADH gives its electrons to the terminal electron acceptors (O2) via electron transport chain. This ensures that the process of glycolysis is continued in cells to breakdown the glucose into pyruvate.
It is called hydrosphere
It is the total water in Earth.