Answer:C
Explanation:When the ball it up high it holds gravitational potential energy, as it rolls down it gain kinetic energy which is then turned into heat energy due to friction
The two strands of a DNA molecule have complementary base pairs, the nucleotide sequence of each strand automatically supplies the information needed to produce its partner.
Ans.
Steroids are defined as active organic bio-molecules, having four rings with a specific molecular configuration. Steroids play role in two major functions: as hormones or signaling molecules and as structural components of plasma membrane.
Examples of steroid hormones are estrogen, progesterone, and cortisol. Thus, the correct answer is 'option b). they serve as chemical messengers.'
