Name the different types of accesory excretory organs and their excretory substances in human beings
Answers
Answer: In addition to the urinary system, the skin, lungs and liver of vertebrates are accessory excretory organs.
(1) Skin: Human skin possesses glands for secreting two fluids on its surface, namely sweat from the sweat glands and sebum from sebaceous glands. (Fig. 19.7). Sweat is a watery fluid containing in solution primarily contains sodium-chloride, lactic acid, urea, amino acids and glucose. It helps in excreting mainly water and sodium chloride, and a small amount of urea and lactic acid.
Sebum is a wax-like secretion which helps to excrete some lipids such as waxes, sterols, other hydrocarbons and fatty acids on the skin.
(B) Lungs: Lungs which are the main respiratory organs of vertebrates, help to eliminate the entire volume of carbon dioxide produced in the body, as well as some moisture, during expiration. The lungs maintain the blood-gas homeostasis through elimination of carbon dioxide. When lungs fail to eliminate enough carbon dioxide, the kidneys attempt to compensate. They change some of the carbon dioxide into sodium bicarbonate, which becomes part of the blood buffer system.
SUMMARY
(1) Excretion is the removal of nitrogenous waste products from the body. (2) Animals are classified as ammoniotelic, ureotylic, uricotylic and guanotelic according to the predominant excretory product excreted. (3) Kidneys are the most important excretory organs of mammals. Through filtration, reabsorption and active transport, waste is remove, but kidneys conserve substances useful to the organisms. (4) In general, kidneys regulate the intake and the outflow of water and salts in the blood and help to maintain homeostasis. (5) Regulation of kidney function is achieved by certain hormones such as antidiuretic hormone, aldosterone and angiotensin. (6) Skin and lungs also act as accessory excretory organs. mate i am also attaching a picture of Vertical Section of the Skin
Answer:
The accessory excretory organs in Human beings are:
(i) Kidneys: They are the main excretory organs of our body. Lungs, Skin and Liver also carry out excretion as a Secondary function to excrete Toxic Liquids in the form of Urine.
(ii) Skin: It contains large number of Sweat glands which are highly supplied with Blood Capillaries from which they excrete Sweat and few metabolic wastes such as Toxic salts.
(iii) Liver: It produces metabolic wastes like Urochrome (excreted through Urine), Bile pigments, Bilirubin and Biliverdin, which are Metabolic wastes of Haemoglobin of dead Red Blood Cells (R.B.C's). The Cholesterol and derivatives of Steroid hormones, accessory Alkaloid salts and Drug-Vitamins are also excreted through Bile, (Liver is also involved in Urea formation).
(iv) Lungs: It is involved in the gaseous exchange during the process of Respiration. A Metabolic waste like Carbon Dioxide (CO) is released through Lungs.
(v) Intestine (Large): Excess salts of Calcium, Magnesium and Iron are excreted by Large Intestine for elimination along with the faeces.
(vi) Small amount of Nitrogenous wastes are also excreted through Saliva and Tears.