Topic L (Excretion)

Question 1

Excretion

Answer 1

The removal of waste products of metabolism

Question 2

Ureter

Answer 2

Transports urine from the kidney to the bladder

Question 3

Urethra

Answer 3

Transports urine out of the body

Question 4

Urea

Answer 4

Produced from the breakdown of excess amino acids in the liver

Question 5

Urine

Answer 5

A solution of urea + water + salts, stored in the bladder before being released from the body

Question 6

Nephron

Answer 6

Functional filtering unit of the kidney, also known as kidney tubules

Question 7

Bowmans capsule

Answer 7

Hollow cup of cells surrounding the glomerulus

Question 8

Glomerulus

Answer 8

A dense network of capillaries where water, ions, glucose and urea are filtered from the blood into the tubules

Question 9

Glomerular filtrate

Answer 9

The fluid forced out of the glomerulus under high pressure

Question 10

What does glomerular filtrate contain?

Answer 10

Glucose, urea, ions

Question 11

What glomerular filtrate does not contain?

Answer 11

Blood cells, proteins

Question 12

Proximal convoluted tubule

Answer 12

Site where the majority of glomerular filtrate is reabsorbed

Question 13

What is reabsorbed back into the blood stream? Which process?

Answer 13

Glicose, active transport

Question 14

Loop of Henle

Answer 14

A U-shaped loop that runs down into the medulla of the kidney

Question 15

What is Loop of Henle’s main role

Answer 15

Concentrating the fluid in the tubule to allow more water to be reabsorbed into the blood

Question 16

Collecting duct

Answer 16

The tubule that receives urine from numerous nephrons.

Question 17

What controls the permeability of the wall’s of the collecting duct?

Answer 17

ADH hormone

Question 18

Ultrafiltration

Answer 18

The process where fluid is forced out of the glomerulus under high pressure

Question 19

Selective reabsorption

Answer 19

The process where the substances we need are absorbed into the blood stream.

Question 20

Active transport

Answer 20

The transport of substance across a biological membrane against a concentration gradient, which requires energy

Question 21

Osmoregulation

Answer 21

The hormonal control of water level in the blood

Question 22

ADH - stands for?

Answer 22

Anti diuretic hormone

Question 23

ADH

Answer 23

The hormone which increases the permeability of the collecting ducts allowing more water to reabsorbed back into the blood

Question 24

Hypothalamus

Answer 24

A region of brain which are sensitive to the solute concentration of the blood

Question 25

Pituitary gland

Answer 25

A small gland in the brain that releases several hormones including ADH

Question 26

Negative feedback

Answer 26

Any mechanism which reverts a change in a system back to its normal value.

Question 27

Homeostasis

Answer 27

The maintenance of a constant internal environment

Question 28

Egestion

Answer 28

Removal of faeces

Question 29

How does a nephron begin?

Answer 29

With a glomerulus

Question 30

What follows glomerulus?

Answer 30

Bowman's capsule

Question 31

What is the tubule before loop of Henlé called?

Answer 31

Proximal convoluted tubule

Question 32

What is the tubule after loop of Henlé called?

Answer 32

Distal convoluted tubule

Question 33

What substances are reabsorbed during selective reabsorption? (3)

Answer 33

1) ALL Glucose 2) SUFFICIENT salt 3) SUFFICIENT water

Question 34

What process helps selectively reabsorb water?

Answer 34

Osmosis

Question 35

How are mineral ions reabsorbed into the blood stream?

Answer 35

Active transport

Question 36

Where does the nephron finally get to?

Answer 36

Collecting duct

Question 37

Main roles of kidneys (3)

Answer 37

1) Removal or urea 2) Adjustment of salt levels in the water 3) Adjustment of water content of the blood

Question 38

Where does most of selective reabsorption happen?

Answer 38

Proximal convoluted tubule

Question 39

What will happen if there is not enough water in the cells?

Answer 39

Reactions in cytoplasm would not occur

Question 40

What will happen if there is too much water in the cells?

Answer 40

Cells may rapture

Question 41

What are the 3 main mays of water leaving the body?

Answer 41

1) Sweating 2) Breathing 3) Urinating

Question 42

What mechanism controlls the process of osmoregulation

Answer 42

Negative feedback

Question 43

Describe negative feedback in terms of osmoregulation

Answer 43

When water content gets too high or too low a mechanism will be triggered to bring the level back to normal

Question 44

How does ADH travel through the body?

Answer 44

Blood

Question 45

Under what conditions less water will be stored? (3)

Answer 45

1) Cold temp 2) No sweating 3) Well hydrated

Question 46

Under what conditions more water will be stored? (3)

Answer 46

1) Hot temp 2) A lot if sweating 3) Poor hydrated