Q: The brain and spinal cord are part of what system, which serves as a control center? Choices: - primary nervous system - active nervous system - large nervous system - central nervous system A:
central nervous system

(Question)
Q: What substances serve as catalysts in most of the biochemical reactions that take place in organisms? Choices: - hormones - carbohydrates - iseotrops - enzymes A:
(Answer)
enzymes

Ques: Q: The long mouth-tube that some insects use to suck up the nectar of the flower is called what? Choices: - stamen - prosthesis - pistil - proboscis A:
Ans: proboscis

(Q).
Q: What force is perpendicular to velocity and causes uniform circular motion? Choices: - centripetal torque - circular friction - tangential force - centripetal force A:
(A).
centripetal force

Ques:Q: What is the name for the stratospheric gas layer that protects living things from uv radiation? Choices: - carbon layer - atmospheric layer - toposphere - ozone layer A:

Ans:ozone layer

Ques:Q: Convection in which part of the earth drives the movement of the plates of lithosphere over the earth's surface? Choices: - atmosphere - ocean - upper crust - mantle A:

Ans:
mantle