Excretion is :-
Metabolism of food materials produce some waste materials. Removal of these waste materials from the body is called excretion.
In mammals, the urinary bladder opens into :-
Urinary bladder opens into urethra in mammals
Malpighian corpuscles occur in :-
Malpighian corpuscles are also known as renal corpuscles you know that the longitudinal section of kidney shows two distinct regions - an outer cortex and an inner medulla , the cortex region consists of Malpighian body , proximal and distal convoluted tubules while the medulla contains Henle's loop , the Malpighian corpuscles contains glomerulus and bowman's capsule which comes in cortex region.
The xylem in plants are responsible for
The main function of xylem is to transport water from the roots to the shoots and leaves,
"Homeostasis" term was proposed by :-
The concept of the regulation of the internal environment was described by French physiologist Claude Bernard in 1849, and the word homeostasis was coined by Walter Bradford Cannon in 1926.
In insects, there is no structural or functional relationship between excretory or digestive system except in
Excretory materials are formed in :-
Animals accumulate ammonia, urea, uric acid, carbon dioxide, water and ions like Na+, K+, Cl, phosphate, sulphate, etc., either by metabolic activities or by other means like excess ingestion. As metabolism is a characteristic feature of living cells. All the cells produce metabolic wastes. These substances have to be removed totally or partially.
Diameter of the renal afferent vessel is :-
The diameter of the renal afferent vessel is larger as compared to efferent vessel so that more blood may flow in the efferent arteriole thereby increasing the blood pressure in glomerus.
Nitrogenous waste products are eliminated mainly as :-
Animals are categorised on the basis of their nitrogenous waste products. They are:
1. Ammonotelic animals are animals which excrete nitrogenous wastes as ammonia.
2. Ureotelic animals are animals which excrete nitrogenous wastes as urea.
3. Uricotelic animals are animals which excrete nitrogenous wastes as uric acid.
Hence, Tadpole is ammonotelic because it lives in water and has a large volume of water that is needed for the elimination of ammonia. It can eliminate ammonia was rapidly as it is formed, into the surrounding water.
Adult frog is ureotelic because urea is far less toxic than ammonia and can be concentrated in the urine and excreted at slower rate.
Which blood vessel contains the least amount of urea?
Blood enters the kidney via the renal artery. Urea is removed from the blood by the kidneys. Hence, when blood leaves the kidney via a renal vein, the amount of urea is less in blood compared to the level of urea in blood contained in any other blood vessel.
Reabsorption of useful substances from glomerular filtrate occurs in :-
The cells lining the proximal convoluted tubule are well adapted for reabsorption of materials from the filtrate. The cells reabsorb entire glucose, amino acids, most of the inorganic ions (Na+, K+, Cl ), much of the water as well as some urea from the filtrate.
Which one is uricotelic ?
Uricotelic organisms are the organisms which excrete nitrogenous waste substances in the form of uric acid, e.g., Lizard, some insects and birds.
What will happen if one kidney is removed from the body of a human being ?
Most people with one kidney live healthy, normal lives with few problems. In other words, one healthy kidney can work as well as two.
In cockroach, the excretory product is :-
Excretion in cockroach is uricotelic meaning, it excretes uric acid or its salts as a result of deamination.
The mechanism of urine formation in nephron involves :-
This phenomenon of filtration of glomerular blood through the filtration slits is called as glomerular filtration. It is also called as ultrafiltration because relatively larger molecules like proteins can not pass through filtration slits. Hence the mechanism of urine formation in nephron involves 'Ultrafiltration'
In diabetes mellitus the patient drinks more water as there is urinary loss of :-
Thirst and frequent urination are two classic diabetes mellitus signs caused by high glucose levels in the blood. As kidneys work harder to filter out the glucose, they also pull more fluids from other tissues, which is why the patient urinates more often than usual. This is the way in which the body indicates that it needs to replenish the liquids it's losing.
The hormone that promotes reabsorption of water from glomerular filtrate is :-
Vasopressin that is also called antidiuretic hormone released by hypothalamus for controlling the water and electrolyte balance in the kidney at the renal cortex.
Main function of kidney is
Ultrafiltration and reabsorption in the kidney are carried out by its functional unit called nephron. Ultrafiltration occurs between the glomerulus and Bowman's capsule of the nephron. Ultrafiltration, selective reabsorption, and passive absorption all occur in the kidneys during the process of urine formation specifically in the nephron. Ultrafiltration means the diffusion of blood, including plasma to nephron to be filtered. Red blood cells and plasma protein cannot pass through ultrafiltration membrane because their size is too big. Reabsorption includes the active and passive transport. Water is absorbed by osmosis or via aquaporin. Ions (e.g:Na+) is reabsorbed by active transport while glucose, amino acids, and small hydrophobic molecule can reabsorb by diffusion or facilitated diffusion. The process of reabsorption occurs in the renal tubule.
Urea is transported by :-
Plasma is the liquid portion of the blood and thus carries nutrients and excretory products to their respective tissues and organs.
Micturition is :-
Micturition or urination is the process of expelling urine from the bladder. This act is also known as voiding of the bladder. The excretory system in humans includes a pair of kidneys, two ureters, a urinary bladder and a urethra.
Ornithine cycle performs :-
Ornithine cycle helps in excretion. It helps in conversion of excess of amino acids into urea in liver.The ammonium ions enter urea cycle and get converted into urea. The urea formed in liver is transported to kidney through circulation and finally gets excreted.
The snakes living in deserts are mainly :-
Reptiles or birds, that excrete most of their waste nitrogen in the form of uric acid, are called uricotelic. Uric acid is formed from ammonia mostly in the liver and to some extent in the kidneys. The process is highly energy dependant, but is much less toxic than both ammonia and urea and it is almost insoluble in water and can be eliminated from the body in nearly a solid state, saving a lot of water. Since kidneys can handle the nitrogenous wastes only in solution, reptiles and birds pass a dilute solution of uric acid into the cloaca, where water is absorbed and solid uric acid is eliminated along with faeces.
Which excretory material is least toxic :-
Ammonia is the most toxic form and requires large amount of water for its elimination, whereas uric acid, being the least toxic
Correct order of excretory organs in cockroach, earthworm and rabbit respectively :–
The excretory organ of cockroach is the Malpighian tubules. It is found at the junction of the midgut and hindgut and is about 150 in number.
Almost every segment of the earthworm has a pair of excretory organs, known as nephridia. Each nephridium is made up of a coiled tube that opens into the body cavity.
Rabbit has a pair of kidneys on either side of the body as an excretory organ. So, the correct answer is option B.
The yellow colour of urine of the vertebrates is due to :-
The yellow colour of urine of the vertebrates is due to Urochrome.