alimentary canal

Question 1

What is Ingestion?

Answer 1

taking food in through the mouth and swallowing

Question 2

What is digestion?

Answer 2

breaking down large insoluble molecules into smaller soluble molecules

Question 3

What is absorption?

Answer 3

the movement of small molecules out of the gut and into the blood by diffusion and active transport

Question 4

What is egestion?

Answer 4

passing out undigested food as faeces through the anus

Question 5

What is assimilation?

Answer 5

building larger biological molecules from small soluble molecules

Question 6

What is chemical digestion?

Answer 6

saliva is secreted which makes food easier to swallow. the amylase inside it breaks down the starch into maltose

Question 7

What is mechanical digestion?

Answer 7

chewing, churning food in the stomach to increase the surface area for enzymes.

Question 8

what is amylase?

Answer 8

an enzyme with optimum pH of 7
denatures in eh stomach because the pH is 2

Question 9

how is food transported through the intestine and the oesophagus?

Answer 9

food is shaped into a bolus and it travels down the throat via peristalsis

Question 10

what does protease do?

Answer 10

it breaks down proteins

Question 11

what secretes pepsin?

Answer 11

gastric glands

Question 12

functions of hydrochloric acid

Answer 12

maintains the optimum pH for pepsin
kills bacteria

Question 13

what prevents hydrochloric acid from burning the stomach walls?

Answer 13

the mucus lining

Question 14

what enzyme does the pancreas secrete into the duodenum?

Answer 14

trypsin, lipase, amylase

Question 15

what also breaks down proteins?

Answer 15

trypsin in the duodenum

Question 16

what breaks down lipids

Answer 16

lipase

Question 17

what enzyme does the duodenum wall secrete?

Answer 17

maltase

Question 18

what enzyme breaks down peptides?

Answer 18

peptidases

Question 19

two functions of bile?

Answer 19

neutralises stomach acid
breaks down fatty droplets int more smaller droplets to increase surface area for lipase to work on

Question 20

how is the small intestine adapted for diffusion?

Answer 20

many villi and micro villi which increases the surface area.
the villi cells are one cell thick for short diffusion distance
there is a capillary network and a lacteal which maintains the concentration gradient

Question 21

What does the large intestine do?

Answer 21

egestion