Answer:
D. Cyclin
Explanation:
Cyclins drive the events of the cell cycle by partnering with a family of enzymes called the cyclin-dependent kinases (Cdks). A lone Cdk is inactive, but the binding of a cyclin activates it, making it a functional enzyme and allowing it to modify target proteins.
If your car is changing speed by accelerating or decelerating, or changing directions by turning or hitting a bump, your body can sense these accelerations. You might be pressed against the back of your seat while speeding up or against the car door as you turn for example. If you are cruising at a constant speed, with no changes in speed or direction, you wouldn't be able to feel it. You would need to use your other senses. You could see the scenery going by through the windows, with closer objects moving by more quickly than objects in the distance. You could also hear sounds like the wind rushing by and the hum of the tires rolling on the highway.
Answer:
Parathyroid hormone increases the level of calcium while calcitonin hormone decreases the level of calcium in the blood.
Explanation:
Parathyroid hormone is a type of harmone which is responsible for balancing calcium in our body. When the calcium level lowers in our body, parathyroid hormone is secreted and calcium is absorbed from the bones and fullfilled the requirement of the body. If the tumor secreted calcitonin hormone instead of parathyroid hormone, the calcium level in the blood is lowered because it acts to the opposite of parathyroid hormone.