The liquid which leaves your body through the urethra. It contains water, salts urea and other chemicals.
The poisonous waste compound produced when excess amino acids are broken down in your liver
A polymer made up of amino acids joined by peptide bonds. The amino acids present and the order in which they occur vary from one protein to another.
Chemical needed in very small amounts as part of a balanced diet to keep the body healthy
Reddish brown organs which get rid of waste urea from the body and balance the water and mineral ion concentration of the blood
Charge particles formed when an atom loses or gains electrons during the formation of ionic bonds
The maintenance of a constant internal environment in the body
A type of sugar: a mono saccharide with 6 carbon atoms (a hexose sugar).
A list of often difficult or specialised words with their definitions.
The amount of a substance (solute) in a solution
The basic unit from which all living organisms are built up, consisting of a cell membrane surrounding cytoplasm and a nucleus.
Humans have two kidneys. They are complex organs that are vital for life. The kidneys produce urine which is made up of waste products, excess mineral ions and excess water from the body.The main job of your kidneys is to regulate the amount of water in the body and balance the concentration of mineral ions in the blood. They also get rid of waste products, especially a nitrogen-containing compound called urea. At the same time they hold on to useful substances such as glucose and protein so none is lost from the body.
Your body is made up of millions of cells. For them to work properly, the conditions inside your body need to be as constant as possible. However everything you do tends to change your internal conditions. You take millions of new molecules into your body when you eat and digest food, you release heat energy every time you move about, the amount of water you take into and lose from your body varies all the time and your cells are constantly producing poisonous waste.
Homeostasis describes the functions of your body which work to keep your internal environment constant within a very narrow range. One of your most important organs of homeostasis is the kidney.
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