Answer:
NUMEROUS DISEASES SPREAD
Explanation:
When Columbus stumbled upon the Americas, he and his crew were carrying numerous diseases, including smallpox, which killed 50% - 90% of the Native people's population.
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.
Answer:
A feedback loop is a biological occurrence where the output of a system amplifies the system (positive feedback) or inhibits the system (negative feedback).
Explanation:
Example, during blood clotting, a cascade of enzymic proteins acitvates each other, leading to the formation of fibrin clot that prevents further blood loss.
Excess carbohydrates and fats are stored; excess proteins are not
