I think the relationship is Commensalism ( relationship between two organisms in which one benefits and the other does not benefit nor is harmed ) because the bird benefits and the cow does not benefit nor is harmed. Hope this helped ☺
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.
Type 1 Diabetic here! I can help!! so basically the receptor for insulin is a large protein that binds to insulin and passes its message into the cell. It has several functional parts. Two copies of the protein chains come together on the outside of the cell to form the receptor site that binds to insulin.
I hope this helped :)
Zit sure has to be B. Pollution