Give scientific reasons for the following statement:
Testes are present in scrotum.
Testes:
Testes are present in scrotum:
Veins have valves present in them.
Give scientific reasons for the following statements:
We cannot distinguish colors in the moonlight.
Give scientific reasons for the following statements.
Blood flows in arteries with spurts and high pressure.
Give scientific reasons for the following statement-
People living in hilly regions usually suffer from simple goitre.
Blood group AB is called universal recipient.