Excretory Products and their Elimination

PCT

________ is lined by simple cuboidal brush border epithelium which increases the surface area for reabsorption.

Sebaceous glands

________ eliminate certain substances like sterols, hydrocarbons, and waxes through sebum.

DCT

________ is also capable of reabsorption of HCO3- and selective secretion of hydrogen and potassium ions and NH3 to maintain the pH and sodium- potassium balance in the blood.

hairpin shaped Henles loop

A(n) ________ is the next part of the tubule which has a descending and an ascending limb.

Malpighian corpuscle

The ________, PCT, and DCT of the nephron are situated in the cortical region of the kidney whereas the loop of Henle dips into the medulla.

Ammonia

________ produced by metabolism is converted into urea in the liver of these animals and released into the blood which is filtered and excreted out by the kidneys.

efferent arteriole

The ________ emerging from the glomerulus forms a fine capillary network around the renal tubule called the peritubular capillaries.

Urine formation

________ involves three main processes namely, glomerular filtration, reabsorption, and secretion, that take place in different parts of the nephron.

Angiotensin II

________ also activates the adrenal cortex to release Aldosterone.

JGA

________ is a special sensitive region formed by cellular modifications in the distal convoluted tubule and the afferent arteriole at the location of their contact.

body fluid volume

An increase in ________ can switch off the osmoreceptors and suppress the ADH release to complete the feedback.

Malpighian tubules

________ are the excretory structures of most insects including cockroaches.

Aldosterone

________ causes the reabsorption of Na+ and water from the distal parts of the tubule.

ADH

________ can also affect kidney function through its constrictor effects on blood vessels.

GFR

A fall in ________ can activate the JG cells to release renin which can stimulate the glomerular blood flow and thereby the ________ back to normal.

Protonephridia

________ are primarily concerned with ionic and fluid volume regulation, i.e., osmoregulation.

Reabsorption

________ is minimum in its ascending limb.

convenient artery

Blood drained from a(n) ________ is pumped into a dialyzing unit after adding an anticoagulant like heparin.

ANF

________ can cause vasodilation (dilation of blood vessels) and thereby decrease blood pressure.

humans

In ________, the excretory system consists of a pair of kidneys, one pair of ureters, a urinary bladder, and a urethra.

nephron

Each ________ has two parts- the glomerulus and the renal tubule.

excrete nitrogenous wastes

Reptiles, birds, land snails, and insects ________ as uric acid in the form of pellets or paste with a minimum loss of water and are called uricotelic animals.

Mammals

________ have the ability to produce concentrated urine.

uric acid

Animals accumulate ammonia, urea, ________, carbon dioxide, water, and ions like Na+, K+, Cl,- phosphate, sulfate, etc., either by metabolic activities or by other means like excess ingestion.

tough capsule

The outer layer of the kidney is a(n) ________.

Vasa recta

________ are absent or highly reduced in cortical nephrons.

Nephridia

________ help to remove nitrogenous wastes and maintain a fluid and ionic balance.

CNS

The ________ passes on motor messages to initiate the contraction of smooth muscles of the bladder and simultaneous relaxation of the urethral sphincter causing the release of urine.

Blood

________ from the glomerulus is carried away by an efferent arteriole.

marine fishes

Mammals, many terrestrial amphibians, and ________ mainly excrete urea and are called ureotelic animals.

NaCl

________ is returned to the interstitium by the ascending portion of the vasa recta.

Bowmans capsule

The glomerulus along with ________ is called the malpighian body or renal corpuscle.

light yellow

The urine formed is a(n) ________ colored watery fluid that is slightly acidic (pH- 6.0) and has a characteristic odor.

Reabsorption of water

________ also occurs passively in the initial segments of the nephron.

glomerular filtration

The kidneys have built- in mechanisms for the regulation of the ________ rate.

Antennal glands

________ or green glands perform the excretory function in crustaceans like prawns.

Human kidneys

________ can produce urine nearly four times more concentrated than the initial filtrate formed.

Kidneys

________ are reddish brown, bean- shaped structures situated between the levels of the last thoracic and third lumbar vertebra close to the dorsal inner wall of the abdominal cavity.

cortex

The ________ extends in between the medullary pyramids as renal columns called Columns of Bertini.

renal tubule

The ________ begins with a double- walled cup- like structure called Bowmans capsule, which encloses the glomerulus.

amount of filtrate

The ________ formed by the kidneys per minute is called the glomerular filtration rate (GFR)

largest gland

The liver, the ________ in our body, secretes bile- containing substances like bilirubin, biliverdin, cholesterol, degraded steroid hormones, vitamins, and drugs.

medulla

The ________ is divided into a few conical masses (medullary pyramids) projecting into the calyces.

gill surfaces

Ammonia, as it is readily soluble, is generally excreted by diffusion across body surfaces or through ________ (in fish) as ammonium ions.

significant quantities of water

Our lungs remove large amounts of CO2 (approximately 200mL /minute) and also ________ every day.

blood pressure

An increase in ________ can increase the glomerular blood flow and thereby the GFR.

Terrestrial adaptation

________ necessitated the production of lesser toxic nitrogenous wastes like urea and uric acid for the conservation of water.

tuft of capillaries

The glomerulus is a(n) ________ formed by the afferent arteriole- a fine branch of the renal artery.

complex tubular

Each kidney has nearly one million ________ structures called nephrons, which are functional units.

PCT

________ also helps to maintain the pH and ionic balance of the body fluids by selective secretion of hydrogen ions, ammonia and potassium ions into the filtrate and by absorption of HCO3- from it.

Protonephridia or flame cells are the excretory structures in Platyhelminthes (Flatworms, e.g., Planaria), rotifers, some annelids, and the cephalochordate

Amphioxus

Each kidney of an adult human measures 10-12 cm in length, 5-7 cm in width, and 2-3 cm in thickness with an average weight of 120

170g

Each nephron has two parts

the glomerulus and the renal tubule

The glomerulus is a tuft of capillaries formed by the afferent arteriole

a fine branch of the renal artery

The tubule continues further to form a highly coiled network

a proximal convoluted tubule

PCT also helps to maintain the pH and ionic balance of the body fluids by selective secretion of hydrogen ions, ammonia and potassium ions into the filtrate and by absorption of HCO3

from it

DCT is also capable of reabsorption of HCO3

and selective secretion of hydrogen and potassium ions and NH3 to maintain the pH and sodium-potassium balance in the blood