excretory system

Question 1

what is excretion

Answer 1

the removal of metabolic wastes

Question 2

what is elimination

Answer 2

the removal of undigested material, bacteria and bile pigments

Question 3

what are the 5 excretory organs

Answer 3

liver, lungs, sweat glands, kidneys and alimentary canal

Question 4

what wastes do the lungs produce

Answer 4

CO2 from cellular respiration

Question 5

what wastes to the liver produce

Answer 5

urea and bile pigments

Question 6

what wastes do the sweat glands produce

Answer 6

salts, urea, and lactic acids

Question 7

what wastes do the kidneys produce

Answer 7

urea, uric acids and creatinine

Question 8

what wastes do the alimentary canal produce

Answer 8

undigested food, bacteria and bile pigments

Question 9

what is the function of proteins in the body

Answer 9

it makes up the structural materials of the cells

Question 10

proteins are broken down into

Answer 10

amino acids

Question 11

proteins become the primary constituents of what

Answer 11

cell structures, enzymes, antibodies and many glandular secretions

Question 12

what is deamination

Answer 12

the process in which excess proteins are converted into urea

Question 13

when does deamination occur

Answer 13

when there are excess amino acids

Question 14

describe the process of deamination

Answer 14

1. The amine group is removed from the amino acids and become ammonia which is highly toxic to your body
2. the ammonia is quickly reacted with CO2 and converted to urea
3. the products of urea and water are then sent to the kidney where they are filtered and sent down to the bladder to be excreted in the urine.

Question 15

what happens to the remaining part of the amino acid once the amino group (NH2) has been removed

Answer 15

it is converted into carbohydrates and used as energy for cellular respiration

Question 16

why does the liver need to convert ammonia to urea quickly

Answer 16

because it is highly toxic and even a little bit can kill you

Question 17

what are 4 functions of the liver

Answer 17

1. deamination
2. detoxifies
3. deactivates
4. breaks down haemoglobin

Question 17

where are small amounts of urea also lost?

Answer 17

sweat glands

Question 18

what is the function of deamination

Answer 18

it deaminates the excess amino acids

Question 19

what is the function of detoxifying

Answer 19

it detoxifies alcohol and other drugs like antibiotics

Question 20

what is the function of deactivating

Answer 20

it deactivates many hormones and converts them to a form that can be secreted by the kidneys

Question 21

what is the function of breaking down haemoglobin

Answer 21

it breaks down old red blood cells to produce bile pigments

Question 22

what is the main function of the skin

Answer 22

to provide a covering over the surface of the body and to regulate temperature

Question 23

how much water do sweat glands secrete each day

Answer 23

500ml

Question 24

what is dissolved in the waters that sweat glands release

Answer 24

sodium chloride, lactic acid and urea

Question 25

explain how sweat is secreted from the glands

Answer 25

a duct carries the sweat to the hair follicle or to the skin surface where it opens at the pore

Question 26

where are sweat glands located

Answer 26

low under the skin

Question 27

where are the kidneys found

Answer 27

in the abdomen

Question 28

how big are the kidneys

Answer 28

11cm

Question 29

what is the functional unit of the kidney

Answer 29

nephrons

Question 30

what is the role of the nephron

Answer 30

to filter the blood and produce urine

Question 31

what carries blood to the kidney

Answer 31

the afferent arteriole of the renal artery

Question 32

what carries blood away from the kidneys

Answer 32

the efferent arteriole to the renal vein

Question 33

what does the ureter do

Answer 33

carries urine to the bladder

Question 34

what is the renal medulla

Answer 34

the inner part of the kidney

Question 35

what is the renal cortex

Answer 35

the outer part of the kidney

Question 36

what does the renal pelvis do

Answer 36

funnels urine into the ureter

Question 37

what are the 3 stages of urine filtration

Answer 37

1. glomerular filtration 2. reabsorption 3. tubular secretion

Question 38

where does glomerular filtration occur?

Answer 38

the glomerulus and glomerular capsule

Question 39

explain how fluid is forced from the blood

Answer 39

the afferent and efferent arterioles have different diameters that creates a high difference in pressure (more blood going in than going out) the fluid seeps the the thin walls of the vessels

Question 40

describe how the structure of the glomerulus and glomerular capsule is suited to allow the escape of filtrate to occur

Answer 40

the blood in the capillaries and the glomerulus is only separated by 2 layers of thin flat cells 1, the capillary wall 2. the wall of the capsule

Question 41

what is the fluid that moves into the nephron called

Answer 41

filtrate

Question 42

what does filtrate contain

Answer 42

water, salts, amino acids, fatty acids, urea, glucose, uric acid. creatinine, hormones, toxins an ions

Question 43

what is not contained in the filtrate

Answer 43

red and while blood cells and plasma proteins

Question 44

why are red, white blood cells and plasma proteins not included in the filtrate

Answer 44

they are to big to diffuse through

Question 45

where does the reabsorption occur

Answer 45

the proximal convoluted tubule and the loop of henle

Question 46

why does reabsorption occur

Answer 46

so many components that are filtered through are of use to the body so their excretion would be bad

Question 47

how are substances reabsorbed by the nephron during the resorption

Answer 47

through an active process called facultative absorption

Question 48

what is facultative absorption

Answer 48

an active process of reabsorbing water controlled by hormones

Question 49

where does tubular secretion occur

Answer 49

the distal convoluted tubule and the collecting

Question 50

what is the the purpose of tubular secretion

Answer 50

to add materials to the filtrate from the blood

Question 51

what are the materials added to the filtrate

Answer 51

potassium, hydrogen ions, creatines and drugs such as penicillin

Question 52

what are the 2 effects of tubular secretion

Answer 52

maintains the blood's pH maintains the urine's pH

Question 53

how does tubular secretion controls the pH of the blood and what is the effect on the urine's pH

Answer 53

out diets contain many acid producing foods that tend to lower the blood's pH so the kidney filters out the acidic elements like hydrogen and ammonium to balance it back up the urine is. consequence is acidic because of the presence of hydrogen and ammonium

Question 54

what is the urines normal pH

Answer 54

6

Question 55

what is the bloods normal pH

Answer 55

7.4 - 7.5

Question 56

describe what happens to the remaining filtrate after tubular secretion

Answer 56

the substances not absorbed drain into the renal pelvis then follow the ureter the the bladder before exiting through the urethra

Question 57

how much water is lost ech day to remove wastes

Answer 57

0.5 L

Question 58

how much water that enters the nephron is reabsorbed

Answer 58

99%

Question 59

what does urine not normally contain

Answer 59

proteins

Question 60

what does urine NEVER contain

Answer 60

glucose

Question 61

the main materials making up urine are

Answer 61

water, urea, uric acid, ions and creatinine

Question 62

what is uric acid and where does it come from

Answer 62

it is produced by the metabolism of purines purines come from the breakdown of nucleic acids like DNA and also occur naturally in foods

Question 63

what is creatinine and where does it come from

Answer 63

it is produced in the muscles from the breakdown of creatine phosphate

Question 64

what is creatine phosphate

Answer 64

a energy rich molecule

Question 65

what are the 4 ways the structure of the kidney and nephron is related to its function

Answer 65

1. large volume of blood going through the kidney's 2. the afferent arteriole having a larger diameter than the efferent 3. the large SA of the tubules for excretion and reabsorption 4. each kidney has 1.2M nephrons

Question 66

how is the renal corpuscle suited to its function

Answer 66

the filtration of blood from the capillary to the glomerulus the formation of filtrate in glomerular capsule

Question 67

how is the proximal convoluted tubule and loop of henle suited to its function

Answer 67

the passive reabsorption of potassium, chlorine and bicarbonate ions the active reabsorption of glucose and sodium absorption of water through osmosis

Question 68

how is the distal convoluted tubule suited to its function

Answer 68

active reabsorption of sodium ions active reabsorption of hydrogen and potassium ions, creatine and drugs such a penecilian

Question 69

how is the collecting duct suited to its function

Answer 69

active reabsorption of water depending on the body's water needs

Question 70

describe the structure of the villi

Answer 70

has microvilli on the SA, has reabsorption and secretion cells, has a lacteal inside that delivers back to lymph system, surrounded by blood capillaries so materials can enter and exit

Question 71

what materials enter the villi through active transport

Answer 71

amino acids and monosaccharides

Question 72

what materials enter the villi through simple diffusion

Answer 72

fatty acids and glycerol and fat soluble vitamins

Question 73

what materials enter the villi through osmosis

Answer 73

water and water soluble vitamins