It is false scientist don't need to repeat an experiment
The right answer is vein (it contains blood and has valves).
The infra-cardiac veins of small and medium caliber possess this system of fight against gravity. The valves consist of a dense connective tissue, surmounted by endothelial cells, corresponding to a fold of the intima. They allow blood circulation in the sense organ / heart but prevent venous reflux.
Answer: The average kinetic energy in an object or substance tells us its mass. Kinetic energy has a direct relationship with mass, meaning that as mass increases so does the kinetic energy of an object.
answer for this question is A
Answer:
A. Integumentary system
Explanation:
The integumentary system consists of the skin,hair and nail. This system consists of the largest organ in the body. The skin helps in protection against pathogens by shielding the internal body system from external objects.
The skin also helps in Vitamin D production through sunlight.
It also helps to prevent dehydration through regulation of water loss.
