excretory products and their elimination

Question 1

most toxic form of nitrogenous waste

Answer 1

ammonia

Question 2

least toxic form of nitrogenous waste

Answer 2

uric acid

Question 3

process oof excreting ammonia and examples of ammonotelic animals

Answer 3

aquatic amphibians, aquatic insects, bony fishes, amoeba, crayfish, hydra, sponges, tadpole of frog

Question 4

how is ammonia excreted out of the body

Answer 4

through simple diffusion across body surfaces or through gills as ammonium ions

Question 5

process of excretion of urea and examples of ureotelic animals

Answer 5

mammals, terrestrial amphibians, marine fishes

Question 6

how and where is urea synthesized in ureotelic animals

Answer 6

ammonia produced by metabolism is synthesized into urea in the liver and released into blood where it filtered out of the kidneys

Question 7

some amount of urea is maintained in the kidney matrix of ureotelic animals - ?

Answer 7

to maintain desired osmolarity

Question 8

how many times less toxic is urea than ammonia

Answer 8

1,00,000 times less toxic

Question 9

process of excretion of uric acid and its examples

Answer 9

uricotelism ; reptiles, birds, land snails, insects

Question 10

uric acid is excreted in the form of

Answer 10

pellet or paste

Question 11

excretory structures in vertebrates

Answer 11

complex tubular structures called kidneys

Question 12

invertebrates excretory structures

Answer 12

simple tubular forms

Question 13

protonephridia or flame cells are the excretory structure in

Answer 13

platyhelminthes(flatworms) - planaris, some annelids, rotifers, cephalocorddates - amphioxus

Question 14

protonephridia function

Answer 14

maintaining ionic and fluid volume- osmoregulation

Question 15

nephridia is found in

Answer 15

earthworms, other annelids

Question 16

function pf nephridia

Answer 16

ionic and fluid volume balance, excretion of nitrogenous wastes

Question 17

malphigian tubules are found in

Answer 17

insects like cockroach

Question 18

antennal or green glands are found in

Answer 18

crustasceans like prawns

Question 19

excretory system in humans contains

Answer 19

a pair of kidneys, pair of ureters, urinary bladder, urethra

Question 20

location of kidneys

Answer 20

between last thoracic vertebrae to 3rd lumbar vertebrae
dorsal inner wall of abdominal wall

Question 21

dimensions of kidneys

Answer 21

10-12 cm in length, 5-7 cm in width, 2-3cm in thickness, 120-170 g

Question 22

describe location of kidneys in humans

Answer 22

the left kidney is a little higher than the right one as the right kidney needs to be a little lower to accomodate the liver

Question 23

concave notch towards the inner surface of kidneys

Answer 23

hilum

Question 24

what passes through hilum

Answer 24

nerves, veins, arteries,ureters

Question 25

outer most covering of kidney

Answer 25

tough capsule made up of white fibrous connective tissue

Question 26

kidney is divided into two regions

Answer 26

outer cortex, inner medulla

Question 27

what arrangement does kidney have with peritoneal cover

Answer 27

peritoneal cover is only present on the ventral side of the kidneys as the dorsal side is fused with abdominal wall - retroperitoneal arrangement

Question 28

medulla is divided into

Answer 28

medullary pyramids

Question 29

medullary pyramids extend into the

Answer 29

calyx

Question 30

the cortex extends in between medullary pyramids as

Answer 30

columns of bertini

Question 31

osmolarity of medullary interstitial fluid is

Answer 31

1200mOsm/L

Question 32

urinary bladder is divided into

Answer 32

neck and body region

Question 33

lenth of ureters

Answer 33

25-3o cm

Question 34

sphincters of urinary bladders

Answer 34

internal involuntary sphincter, external voluntary sphincter

Question 35

where is urine stores

Answer 35

urinary bladder

Question 36

signal to release urine is initiated by

Answer 36

walls of the urinary bladder being stretched

Question 37

stretch receptors on urinary bladder wall send signal to ; nature of signal

Answer 37

voluntary signals to CNS

Question 38

what messages does CNS pass ; outcome ?

Answer 38

motor messages to initiate the contraction of smooth muscles of bladder

Question 39

what muscles contract during micturition

Answer 39

detrusor muscles

Question 40

sphincters of urinary bladder during micturition

Answer 40

sphincter undergo relaxation

Question 41

process of passing of urine is called

Answer 41

micturition

Question 42

neural mechanisms causing micturition is called

Answer 42

micturition reflex

Question 43

adult human excretes

Answer 43

1-1.5 litres of urine per day

Question 44

nature of urine

Answer 44

characteristic odour, light yellow watery fluid, pH of 6.0 ( slightly acidic

Question 45

how much urea is excreted out per day

Answer 45

25-30 gm

Question 46

presence of glucose in urine

Answer 46

glycosuria

Question 47

glycosuria is caused by

Answer 47

low levels of insulin which cause blood glucose levels to increase leading to less reabsorption of glucose and increase in glucose in urine

Question 48

presence of ketone bodies in urine

Answer 48

ketonuria

Question 49

ketonuria is caused by

Answer 49

hyposecretion of insulin, glucose cannot be used for energy, breakdown of fat creating ketone bodies in blood

Question 50

glycosuria and ketonuria are indicative of

Answer 50

diabetes mellitus

Question 51

inflammation of glomeruli and symptoms

Answer 51

glomerulonephritis presence of proteins(albumin) in urine

Question 52

jaundice

Answer 52

bile salts and pigments

Question 53

hyperthyroidism, starvation

Answer 53

creatinine

Question 54

what is nephron

Answer 54

complex tubular structural units of kidneys

Question 55

what is nephron

Answer 55

complex tubular structural units of kidneys

Question 56

parts of nephron

Answer 56

glomerulus and renal tubule

Question 57

what is glomerulus

Answer 57

a tuft of capillaries formed from afferent arterioles, a fine branch of renal artery

Question 58

blood from glomerulus is carried away by

Answer 58

efferent arterioles

Question 59

what is nephron also called

Answer 59

uriniferous tubules

Question 60

the renal tubule begins with

Answer 60

double walled cup like structure called bowman's capsule

Question 61

what does bowman's capsule enclose

Answer 61

glomerulus

Question 62

glomerulus and bowman's capsule is called

Answer 62

malphigian tubules or renal corpuscle

Question 63

the malphigian body continue as

Answer 63

a highly coiled network called proximal convoluted tubules

Question 64

PCT is lined by

Answer 64

brush bordered cuboidal epithelium

Question 65

pct descend into

Answer 65

loop of henle

Question 66

loop of henle consists of

Answer 66

an ascending arm and descending arm

Question 67

the ascending limb continues as

Answer 67

a highly coiled tubular structure called distal convoluted tubule

Question 68

the DCTs of many nephrons open into a straight tube called

Answer 68

collecting duct

Question 69

the collecting ducts converge

Answer 69

and open into the renal pelvis throught m medullary pyramids in the calyx

Question 70

collecting ducts open enter throught the medulla region and form

Answer 70

ducts of belllinii

Question 71

collecting ducts open enter throught the medulla region and form

Answer 71

ducts of belllinii

Question 72

what structures lie in the cortical region of nephron

Answer 72

malphigian corpuscles pct, dct

Question 73

what structures lie in the medulla

Answer 73

loop of henle

Question 74

cortical nephrons

Answer 74

loop of henle is short, does not dip into medulla, 80% of all nephrons, malphigian body is in cortex

Question 75

juxta-medullary nephron

Answer 75

20%, loop of henle is long and dips into medulla, Vasa recta is present, helps in concentrated urine formation

Question 76

the efferent arterioles emerging from glomerulus forms a fine capillary network around renal tubule called

Answer 76

peritubular capillaries

Question 77

3 main processes of urine formation

Answer 77

glomerular filtration, reabsorption, secretion that rahe place in different parts of nephron

Question 78

net pressure that causes fluid to filter out of glomerulus into capsule

Answer 78

20mmhg

Question 79

first step in urine formation

Answer 79

blood filtration-glomerular filtration

Question 80

how much blood is filtered by kidneys per minute

Answer 80

1100-1200 ml it constitutes roughly 1/5th of the blood pumped out by each ventricle i in a minute

Question 81

what causes filtration of blood

Answer 81

glomerular capillary blood pressure

Question 82

what causes filtration of blood

Answer 82

glomerular capillary blood pressure

Question 83

3 layers of glomerular filtration layer

Answer 83

endothelium of glomerular blood vessels, epithelium of bowman's capsule, basement substance in between

Question 84

epithelial cells of bowman's capsule

Answer 84

podocytes

Question 85

arrangement of podocytes

Answer 85

arranged in an intricate manner so as to leave some minute space called filtration slits or slit pores

Question 86

GFR in a healthy individual

Answer 86

125ml/min, 180 litres per day

Question 87

what is JGA

Answer 87

a special sensitive region formed by cellular modifications of dct and afferent arterioles at the place of their concact

Question 88

a fall in gfr activates jg cells to release

Answer 88

renin; increase glomerulus blood flow and gfr

Question 89

how much urine is formed in a day

Answer 89

1.5 litres

Question 90

how m much filtrate has to be reabsorbed by renal tubules

Answer 90

99%

Question 91

what cells perform reabsorption

Answer 91

tubular epithelial cells of nephron by active or passive mechanism

Question 92

substance reabsorbed actively

Answer 92

glucose, amino acids, Na+

Question 93

substances reabsorbed passively

Answer 93

water and n2 wastes

Question 94

where does reabsorption of water take place

Answer 94

in initial segments of nephron

Question 95

tubular secretion

Answer 95

tubular secretion helps in ionic and acid base balance of body fluids

Question 96

tubular cells secrete

Answer 96

H+,K+ and ammonia into filtrate

Question 97

why is pct lined by brush bordered epithelium

Answer 97

to increase surface area for absorption

Question 98

what is absorbed by pct

Answer 98

nearly all essential nutrients, 70-80% of electrolytes and water

Question 99

selective secretion of pct

Answer 99

selective secretion of H+,K+, ammonia into filtrate and absorption of HCO3- from filtrate

Question 100

selective secretion of pct maintains

Answer 100

pH and ionic balance

Question 101

where does conditional reabsorption of na+ and water take place

Answer 101

dct

Question 102

reabsorption in dct

Answer 102

HCO3-

Question 103

selective secretion in dct

Answer 103

maintains ph and sodium potassium balance in blood, H2,K+,NH3

Question 104

where is reabsorption minimum in loop of henle

Answer 104

ascending limb

Question 105

role of ascending limb

Answer 105

Significant role in maintenance of high osmolarity of medullary interstitial fluid

Question 106

the descending limb is permeable to

Answer 106

water, almost impermeable to electrolytes

Question 107

effect of descending limb on filtrate

Answer 107

concentrate filtrate as it moves down

Question 108

the ascending limb is permeable to

Answer 108

electrolytes, impermeable to water

Question 109

the ascending limb is permeable to

Answer 109

electrolytes, impermeable to water

Question 110

effect of ascending limb on filtrate

Answer 110

dilutes filtrate as it moves up due to passage of electrolytes actively or passively

Question 111

where does collecting ducts extend to

Answer 111

from cortex to inner parts of medulla

Question 112

large amounts of water is absorbed by

Answer 112

collecting duct to produce concentrated urine

Question 113

how does collecting duct play role in maintaining osmolarity

Answer 113

collecting ducts allow passage of small amounts of urea into medullary interstitium

Question 114

selective secretion of collecting ducts

Answer 114

H+ and K+

Question 115

selective secretion of collecting ducts

Answer 115

H+ and K+

Question 116

who has the ability to produce concentrated urine

Answer 116

mammals

Question 117

segments of nephron playing a significant role in concentration of urine

Answer 117

vasa recta, henle loop

Question 118

the capability of concentration of urine relies on the

Answer 118

length of the henle loop

Question 119

the flow of filtrate in both limbs of henle loop is

Answer 119

is in opposite directions