Blood enters glomerular capillaries through _____ arteriole and leaves through _____ arteriole:
Glomerulus is a tuft of capillaries formed by the afferent arteriole – a fine branch of renal artery. Blood from the glomerulus is carried away by an efferent arteriole.
The following substances are the excretory products in animals. Choose the least toxic form among them?
Uric acid is the least toxic ions. Insects, land tortoises, lizards and birds change most of their nitrogenous waste into uric acid. It is the least toxic because it is insoluble in water as there are in solid form, thus, contains the/least water. In birds, uric acid mixes with undigested food to form the bird dropping. Urea moves to blood get filtered and eliminated with water in urine via kidneys. Ammonia is very toxic and needs water for diffusion. Carbon dioxide excretion takes place through the lungs.
During micturition, the muscles of urinary bladder and urethral sphincters will
During micturition, parasympathetic stimulation causes the detrusor muscle to contract and the internal urethral sphincter to relax. The external urethral sphincter (sphincter urethrae) is under somatic control and is consciously relaxed during micturition. In infants, voiding occurs involuntarily.
A renal corpuscle is :
Glomerulus alongwith Bowman’s capsule is called the malpighian body or renal corpuscle.
pH of urine under healthy conditions is :
The pH of urine under healthy conditions is slightly less than 7 so, slightly acidic in nature.
__________ is a yellow pigment that is formed after dead blood cells are processed in the liver. It is also primarily responsible for the yellow colour of urine.
Urochrome is the yellow pigment responsible for the characteristics of urine color.
This pigment is produced by the breakdown of red blood cells in the liver.
Hence it is a product of hemoglobin metabolism eliminated through urine.
Homeostasis in the body is largely maintained by : excretion and osmoregulation egestion and osmoregulation excretion and egestion osmoregulation, excretion and egestion Homeostasis is the maintenance of constant body temperature. It is mainly maintained by excretion and osmoregulation, which is the function of kidney.
Homeostasis is the maintenance of constant body temperature. It is mainly maintained by excretion and osmoregulation, which is the function of kidney.
Which of the following is not a part of glomerular filtrate?
Glomerular filtrate contains glucose, inorganic salts and creatinine but it do not contain globulins protein.
Read the following :
i. Infants and toddlers are often under habit of bed wetting since micturition is a reflex process.
ii. Adults and grown up children can control this reflex process, voluntarily to some extent.
The process of release of urine is called micturition and the neural mechanism causing it is called the micturition reflex. Adults and grown up children can control the reflex process of micturition voluntarily to some extent.
Urinary bladder is absent in :
Snakes, crocodiles, and birds don't urinate, urea and other water soluble stuff are pushed out with the faeces. Urinating is a balance between getting rid of waste and keeping hydrated. Birds and reptiles ‘urinate’ in a way to conserve their water. Unlike mammals, which excrete waste fluid (e.g., urea in water) as urine and solid waste as faeces, birds, snakes and crocodiles mix both liquid waste and solid waste into the semi-solid paste. Thus, they do not possess a urinary bladder.
So, the correct answer is option A.
The epithelial cells of Bowman’s capsule are called:
The epithelial cells of Bowman’s capsule called podocytes are arranged in an intricate manner so as to leave some minute spaces called filtration slits or slit pores.
All of the following organs help in excretion except :
Lungs help in excretion of carbon dioxide, liver help in excretion of toxic substance and skin help in removal of extra salts along with sweat.
Ascending limb of Henle’s loop is not permeable for :
Ascending limb of Henle’s is not permeable to water. The descending limb is although permeable to water. Counter current exchange takes place between the loop of Henle’s and arteries surrounding it.
Conditional reabsorption of sodium ions and water takes place in
Conditional reabsorption of sodium ions and water takes place in distal convoluted tubule.
Urea cycle operates in :
Urea cycles operates in liver, where ammonia is converted into urea. Sometimes urea cycle also occurs in kidney.
The physiological unit of a kidney is :
Nephrons are the physical unit or functional unit of kidney. Millions of nephrons are present in each kidney but physiological unit of kidney is urinigerous tubule.
The filtration fraction is the ratio of GFR to RPF where both the values are in ml/min and FF is expressed in percentage. Calculate FF for a normal adult human being, if RPF= 600ml/min :
FF = Filtration fraction,
RPF = Renal plasma flow,
GFR = Glomerular filtration rate = 125ml (for healthy human),
FF = GFR/RPF,
So, FF% = GFR/RPF ×100
= 125/600 ×100
Read the following :
i. Avian kidneys have very short loops of Henle.
ii. Birds are unable to make urine as hypotonic as mammals can.
Avian kidneys have very short loops of Henle. Loops of Henle are used in concentration of urine. Birds make urine highly hypotonic.
Adult human kidney is metanephric. So, first embryonic tubules formed in vertebrates during embryonic development are :
Adult human kidney is metanephric, the third and final excretory organ that develops in a vertebrate embryo. First embryonic tubules formed in vertebrates during embryonic development are pronephric.
During urine formation, the tubular cells secrete ______________ into the filtrate.
During urine formation, the tubular cells secrete substances like hydrogen ions, potassium ions and ammonia into the filtrate.