Human Excretion System

Every day our bodies produce substances dirt and the rest of the body's processes. In order to keep our bodies healthy and free from disease, the dirt and residual substances in our body should be disposed of through the instrumentality of excretion. Ekresi system is the process of spending substances waste products of metabolism that are no longer used by the body.

While the reverse of this system is a system that processes expense secretion of substances that are useful to the body. Human excretion tools such as kidney, skin, liver, lung and colon.

The results of the excretion system can be divided into:

  • Liquid in the form of sweat, urine and bile.
  • Solids in the form of feces.
  • Gases such as CO2.
  • Water vapor in the form of H2O.
  • Ekresi Human Organ
1. Kidney

In the body there is a pair of kidneys, located on the left and right lumbar vertebrae in the abdominal cavity. The location of the left kidney is higher than the right kidney, the right kidney because there are a lot of hearts taking up space. The kidneys function to filter blood.

Kidney consists of three parts:
a. Leather Kidney (cortex)
b. Kidney marrow (medulla)
c. Cavities kidney (pelris)

In the skin there is a tool kidneys called nephrons filter blood. Each nephron is composed of body Malpighi and the channel length (tubules) that curled. Malpighi bodies composed of glomerolus and hoop Bowman. Glomerular blood capillaries form of woven, while Bowman hoops form a thick-walled cup surrounding the glomerulus. Kidney marrow is a gathering place for delicate vessels of the hoop Bowman. These delicate vessels drain the urine into the larger channel and empties into the cavity of the kidney. Furthermore, urine flows through the kidneys (ureters) and placed in the bladder. If the bladder contains a lot of urine, wall pockets so depressed circular muscle at the base of the bag stretch. That places a sense of urination. Further urine excreted through the urinary tract (urethra).

How Kidneys Work

The blood contains a lot of metabolic waste enters the kidneys through the renal arteries. Fluid out of blood vessels into the nephron. Water, sugar, amino acids and urea separated from the blood and then into hoops Bowman. This process is called filtration. From about 180 liters of water filtered by Bowman hoops setipa day, hanyau liter which is excreted as urine. Most of the water is absorbed back in the capillaries. Fluid from the hoop Bowman headed to the collecting duct. In the return journey the absorption of glucose and other substances by the blood flow. This event is called reabsorption. Materials such as urea and salt water to be reabsorbed join urine.

Under normal circumstances, urine contains: water, urea and ammonia which is a revamp sisia protein. Mineral salts, especially salt. Substance that gives color yellow bile in the urine. Excessive substances in the blood such as vitamins, drugs on hormone. If there is protein in the urine, it shows the damage in the kidney.

2. Skin

Through the skin of the waste in the form of sweat released. Skin consists of three layers, namely:

a. Layer of the epidermis (the epidermis)

Epidermis is composed of two layers of the stratum corneum and Malpighi layer. Stratum corneum is the outermost part of the skin consists of dead cells and can peel. Malpighi layer lies beneath the horny layer and consists of living cells. In Malpighi layer contained pigment that gives color to the skin and protect skin from the sun. If Malpighi layer contains no pigment, called albino person.

b. Cuticle layer

Cuticle contains blood vessels, sweat glands, oil glands, hair follicle, nerve endings feeling hot, cold, pain, and touch. Hair root and hair shaft is within a hair follicle. Short hair roots are smooth muscles that serve to uphold hair when feeling cold or scared.

c. Connective tissue under the skin

Connective tissue under the skin contains a lot of fat that are useful as food reserves, retaining body heat and protect the body against external impact.

Aside from being a tool of expenditure, the skin also serves as:

_ Protective body against germs from outside
_ The store excess fat
_ Control body temperature
_ The manufacture of vitamin D and provitamin D

3. Liver

Heart is located in the right abdomen below the diaphragm. The liver produces bile which is then stored in the gall kentong and channeled into the duodenum via the bile duct. Bile comes from the red blood cells that have been damaged and destroyed in the spleen.

Aside from being a means of excretion, liver function:
_ Set the sugar levels in the blood
_ Keep the sugar in the form of glycogen
_ Neutralize toxins that enter the body
_ As a manufacture and fibrinogen protombin
_ As a modifier provitamin A to vitamin A
_ As the formation of urea

4. Lungs

In the process of respiration the waste generated in the form of carbon dioxide and water vapor will come out through the nostrils, the waste must be removed because it can interfere with the function of the body. Humans have a pair of lungs that is located in the chest cavity. Lung function as a respiratory organ that breathe oxygen and emit CO2 + water vapor. Water vapor and CO2 diffuses across the alveoli and then removed through the nostrils.

5. Colon

Located in the abdominal cavity with a length of ± 1 meter. The process of defecation is spending the remainder of these substances digestion through the anus. The result is a solid excretion called feces. In general, the function of the excretory system useless waste and toxic substances from the body, regulates the concentration and volume of body fluids (osmoregulation) empertahankan body temperature within the normal range (thermoregulation), homeostasis.













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