Answer:
Skin is the human body's largest organ.
Explanation:
Body organs aren't all internal like the brain or the heart. There's one we wear on the outside. Skin is our largest organ—adults carry some 8 pounds (3.6 kilograms) and 22 square feet (2 square meters) of it.
The answer for the above question is Mutation.
Mutations are random spontaneous changes that occur suddenly in the DNA. A single mutation can have a large effect, however in may cases evolutionary changes are based on the accumulation of many mutations. The gene flow is any movement of genes from one generation to another and is an important source of mutation
It is NOT C, I got that wrong when I chose C.
Correct answer: A) Extension
Extension is a physical position that occurs when angle between the bones and the limbs of joint increases.
It takes place when there is a contraction of muscles and bones move the joint from a bent to a straight position, it is opposite of flexion, in which the angle between the bones and the limb at the joint decreases.
Example: During straightening of the leg, the angle between the tibia and femur increases, which shows extension has taken place.
Usually during exercise, unlike during rest times the muscle cells need to respire more. So they need more oxygen and glucose for energy and the carbon-dioxide produced as waste must be removed quickly. So when person gets tired or breathes heavily during intensive workouts means they are in need of more oxygen. So the cells starts performing anaerobic(lactic acid ) respiration even though it releases less energy.
