Why do we have kidneys?

Answer 1

kidneys filter out the things our body doesn't need and sends the waste out as urine while sending the "good things", vitamins etc. to the rest of the body.

Answer 2

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Answer 3

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Answer 4

The kidneys are an essential part of our urinary system. We have two kidneys, and they are located on either side of the spine in our lower back. They are about the size fo a fist and are bean shaped.

The primary function of the kidney is to filter wastes from our blood. About 50 gallons of blood enter our kidneys every day. They also process approximately two quarts of extra water and waste products.

The wastes that are filtered and extra water turn into urine. The urine then travels down tubes, called ureters and is stored in the bladder until excretion(urination).

Answer 5

Kidneys are very essential part of our body. Their main function is to filter blood. They filter the blood for food, waist material etc. An individual kidney is capable of filtering about 800Lt's of blood a day. It separates out the waste material from the blood and what is formed is called urine.

Answer 6

Every day, your kidneys process about 200 quarts of blood to sift out about 2 quarts of waste products and extra water. The waste and extra water become urine, which flows to your bladder through tubes called ureters. Your bladder stores urine until you go to the bathroom.

The wastes in your blood come from the normal breakdown of active tissues and from the food you eat. Your body uses the food for energy and self-repair. After your body has taken what it needs from the food, waste is sent to the blood. If your kidneys did not remove these wastes, the wastes would build up in the blood and damage your body.

Without kidneys, you would become toxic and die.

Answer 7

Kidneys help remove poison from our system kidneys also help in removing worn out 'juice' from our system they are attached to the bladder trough a vein

kidneys need water for top performance thats why you should drink water once in awhile

you will know your kidneys are tired and tristy when your urine is dark yellow

Answer 8

functions of kidneys:
Excretion of waste products

The kidneys excrete a variety of waste products produced by metabolism, for example, urea (from protein catabolism) and uric acid (from nucleic acid metabolism).
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Homeostasis

Acid-Base Balance

The kidneys regulate the pH, mineral ion concentration, and water composition of the blood.

By exchanging hydronium ions and hydroxyl ions, the blood plasma is maintained by the kidney at a neutral pH 7.4. Urine, on the other hand, is acidic at pH 5 or alkaline at pH 8.

The pH is maintained through four main protein transporters: NHE3 (a sodium-hydrogen exchanger), V-type H-ATPase (an isoform of the hydrogen ATPase), NBC1 (a sodium-bicarbonate cotransporter) and AE1 (an anion exchanger which exchanges chloride for bicarbonate). Due to the polar alignment of cells in the renal epithelia NHE3 and the H-ATPase are exposed to the lumen (which is essentially outside the body), on the apical side of the cells, and are responsible for excreting hydrogen ions (or protons). Conversely, NBC1 and AE1 are on the basolateral side of the cells, and allow bicarbonate ions to move back into the extracellular fluid and thus are returned to the blood plasma.

Blood Pressure

Sodium ions are controlled in a homeostatic process involving aldosterone which increases sodium ion absorption in the distal convoluted tubules.

When blood pressure becomes low, a hormone called Renin is secreted by cells of the juxtaglomerular apparatus (part of the distal convoluted tubule) which are sensitive to pressure. Renin acts on a blood protein, angiotensinogen, converting it to angiotensin. Angiotensin stimulates the secretion of Aldosterone by the adrenal cortex, which affects the kidney tubules.

Aldosterone stimulates an increase in the reabsorption of sodium ions from the kidney tubules which causes an increase in the volume of water that is reabsorbed from the tubule. This increase in water reabsorption increases the volume of blood which ultimately raises the blood pressure.

Plasma Volume

Any rise or drop in blood osmotic pressure due to a lack or excess of water is detected by the hypothalamus, which notifies the pituitary gland via negative feedback. A lack of water causes the posterior pituitary gland to secrete antidiuretic hormone, which results in water reabsorption and an increase in urine concentration. Tissue fluid concentration thus returns to a mean of 98%.
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Hormone secretion

The kidneys secrete a variety of hormones, including erythropoietin, urodilatin and vitamin D.

Answer 9

your kidneys are a large filtering system that filter out excessive fluids,minerals,vitamins,electrolytes etc from your blood.They also regulate blood pressure and produce a hormone that stimulates the bone marrow to produce red blood cellsThey are essential in maintaining the body's acid- base balance and homeostasis.

Answer 10

There are four reasons:
- ejectin of waste
- keep acid-base balance constant
- regulate volume of blood
- regulate fluid content of blood