It implants itself to the walls of the uterus (endometrium) by umbilical cord.
Answer:
Mitochondrial DNA is circular, so it doesn't shorten when it replicates unlike the rest.
Answer:
One million.
Explanation:
Each kidney contains about one million of nephrons. The nephron is the structural and functional unit of the kidney means that our kidney is made up of nephrons. The main function of nephron is to produces urine in the process of removing waste, toxic and excess substances from the blood. kidney is responsible for the filtration of blood by removing all the waste materials and taken these waste materials to the excretory organs in order to remove from the body.
Answer: Possession of Valves
Explanation: Veins possess valves which ensures that blood flows in only one direction. Valves helps blood to flow back to the heart against gravitational force.
Arteries don't have valves because the pressure originating from the heart is capable of causing the blood to flow in one direction.