Your Answer will be D. <u>Monocytes</u>

If the temperature is too low, enzyme molecules don’t have enough kinetic energy to collide and combine with other substrate molecules. So the enzyme activity/ reaction rate will be very low. The rate will rise again once the temperature increases to its optimum temperature.
But if the temperature is too high, enzyme will be denatured, which means the shape of the active site of the enzyme is changed. It can no long combine with other substrate molecules. The rate will drop significantly. Yet, lowering the temperature won’t help because denaturation is permanent and irreversible.
Answer:
a. back muscles are strong to maintain erect posture.
Explanation:
Human back muscles are categorized as superficial, intermediate and deep muscles. The intrinsic (deep) back muscles of the human back regulate the movement of spine and maintain erect posture of human.
For example, the erector spinae is the largest muscle of the human back and is present on either side of spine. It consists of iliocostalis muscles (lateral), longissimus muscles (intermediate), and spinalis muscles. Together these muscles serve in extension of the spine and maintain the erect posture of the spine.