with the help of a labelled diagram describe how the human body gets rid of its wastes is through excretion
Answers
Although the kidneys are the main organs of excretion, the skin, lungs and liver also help in excretion.
Skin:
Our skin has sweat glands, through which we excrete small amounts of water, urea and salts.
Liver:
The liver excretes bile, which contains bile pigments. These are produced by the breakdown of old RBCs in the liver. As hemoglobin breaks down, its iron is retained, while the pigment (haem) is excreted with the bile. The liver also excretes cholesterol.
Lungs:
The lungs help in getting rid of carbon dioxide, formed as a result of cellular respiration, through exhalation.
Excretory System in Man:
Our excretory system consists of kidneys, blood vessels that join them, ureters, urinary bladder and urethra. They help produce and excrete urine.
There are two bean-shaped kidneys that lie in the abdominal cavity, one on either side of the vertebral column. The kidneys are reddish brown. Each of them is about 10 cm long and weighs about 150 g. Although they weigh less, they receive a lot of blood for filtration.
A volume of blood nearly equivalent to that in the whole body passes through the kidneys every four or five minutes. The kidneys produce urine to filter out the waste products, like urea and uric acid, from the blood.
Answer:
The excretory system is a system of organs that removes waste products from the body. When cells in the body break down proteins (large molecules that are essential to the structure and functioning of all living cells), they produce wastes such as urea (a chemical compound of carbon, hydrogen, nitrogen, and oxygen). When cells break down carbohydrates (compounds consisting of carbon, hydrogen, and oxygen and used as a food), they produce water and carbon dioxide as waste products. If these useless waste products are allowed to accumulate in the body, they would become dangerous to the body's health. The kidneys, considered the main excretory organs in humans, eliminate water, urea, and other waste products from the body in the form of urine.
