Answer: Option D) there are no holes for blood to enter or leave the system
The human cardiovascular system is considered closed because there are no holes for blood to enter or leave the system
Explanation:
The closed circulatory system are made up of blood vessels called arteries from the heart that branch into small units called capillaries but eventually join up with other blood vessels called veins that are connected to the heart. So, blood is always confined to circulate within the blood vessels and the heart as there are no holes for blood to enter or leave the system
Thus, the human cardiovascular system is considered closed
The correct answer is that ammonia is removed from the blood by the liver, which processes it into urea, and discharging it into the circulation.
The liver plays an essential function in the metabolism of proteins. The cells in the liver modify amino acids in foods so that they can be utilized to generate energy, or make fats or carbohydrates.
A toxic component known as ammonia is a waste-product of this procedure. The liver cell transform ammonia to a much less toxic component known a urea, which is discharged into the blood. Urea is then translocated to the kidneys and is removed out of the body in the form of urine.
<span>B: adds aesthetic value to the landscape. Think about it, out of
all your options, that's the one that doesn't really help anything.
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Arteries are under high pressure generated by the heart.
