Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
Structural Variations in Vertebrate Kidney
The structure of the vertebrate kidney is by no means universal. The mammalian kidney consists of an outer granular cortex and an inner striated medulla. The granular appearance of the cortex is due to the presence of glomeruli in this region. Medulla looks striated due to the parallel arrangement of blood vessels and tubules of the nephrons. In fishes, amphibians and reptiles, the renal tubules are short, are devoid of Henle's loop and there is no clear cut distinction between cortex and medulla. In birds there is some degree of spatial organisation of the nephrons so that a small central medulla can be discerned from the outer cortex. This division into cortical and medullary regions is most pronounced in the mammalian kidney.
It is the presence of Henle's loop that enables the avian and mammalian kidney to produce hyperosmotic urine. The ureteral urine in other vertebrates is either hypoosmotic or at best isosomotic to blood. However, terrestrial reptiles and birds produce a semi-solid or solid urine due to reabsorption of water in the cloaca. In birds and mammals, the ureteral urine itself is hyperosmotic to blood. The maximum urine osmolarity attained by the avian kidney is only about twice that of plasma. The urine concentrating ability of the kidney in mammals is related to the habitat. Desert animals produce highly concentrated urine and freshwater animals produce very dilute urine. The kidneys of some desert mammals can produce a urine which is 25 times more concentrated than the plasma. The beaver which has access to abundant water in the environment, on the other hand, has kidneys with only moderate ability to concentrate the urine.
What is dry mass? When biomasses are compared often the method of dry mass is used. The dry mass is the total mass less the water mass of an individual. The total mass is also
A cDNA library is made by using the reverse transcriptase of a retrovirus to synthesize cDNA (complementary DNA) copies of the total mRNA from a cell (or perhaps a subfraction
Morphogenetic Processes We discussed earlier the process through which a fertilized egg assumes the shape of a ball or a sheet of cells around a cavity, called blastula. Cons
What is Prokaryotic Gene Expression ? Control of prokaryotic gene expression occurs primarily at the level of transcription. Prokaryotic genes are arranged in units consisting
what is your name
VERTEBR A T A It is divided into two parts - 1. Agnetha 2. Gnetha S.No. C haracter A gnetha G
Q. Explain about Bequest value of biodiversity? Sometimes people derive satisfaction from the fact that conserved biodiversity may benefit other individuals in the future, givi
The upper or mountain course - Classification of the river Here the water is fast flowing and runs through a 'V' shaped valley with unstable banks. The fast flowing water has
What two biotic factors could affect an antelope living in the Serengeti? The biotic factors that may affect an antelope living in the Serengeti could be:predation by carnivore
Q. Explain about Individual consciousness? The physical brain is not a source of experience as some current neuroscientists now mistakenly believe. While areas of the brain are
Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd