topic 6 - enzymes and the digestive system

Question 1

how do enzymes act as catalysts?

Answer 1

increase the rate of chemical reactions without themselves being consumed or permanently altered by the reaction

Question 2

how can temperature effect enzymes function?

Answer 2

high temperature speeds up the rate of reaction and low temperature slows it down. The enzyme will change shape and the substrate no longer fit. The rate of reaction will be affected, or the reaction will stop.

Question 3

how can pH level effect enzyme function?

Answer 3

the shape of the enzyme, along with the active site will change, altering the rate of reaction.

Question 4

what is the alimentary canal?

Answer 4

long tube of organs makes a pathway for food to travel through the body

Question 5

what is in the alimentary canal?

Answer 5

• mouth
• salivary glands
• oesophagus
• stomach
• pancreas
• liver/gall bladder
• small intestine
• large intestine
• rectum
• anus

Question 6

function of the mouth

Answer 6

• uses mechanical digestion - breaking down food into smaller parts by chewing or biting
• contains the epiglottis - a small flap of tissue that prevents food from entering the trachea

Question 7

function of the salivary glands

Answer 7

• contains salivary amylase which helps break down food into a liquid so it’s easier to digest.
• chemical digestion - use of digestive enzymes and water to break down complex molecules

Question 8

function of the oesophagus

Answer 8

• connects mouth to stomach
• food is propelled through the oesophagus in a matter of seconds through a series of muscle contractions called PERISTALSIS

Question 9

function of the stomach

Answer 9

• inner tissue of stomach is called mucosa. contains cells that produce gastric juice
• gastric juice contains pepsin which helps break down proteins in food
• stomach acid prevents infection and kill bacteria to prevent food poisoning
• has a layer of mucus which prevents cells from being damaged
• Peristalsis churns the food around to break it down so it is easier to digest

Question 10

function of the pancreas

Answer 10

• produces digestive enzymes to break down food into absorbable molecules
• produces insulin which regulates blood sugar levels

Question 11

function of the liver/gall bladder

Answer 11

• the liver produces bile
• the gall bladder stores the bile
• Emulsification is important to ensure the physicochemical stability of the product.
• bile helps to neutralise the strong hydrochloride acid.

Question 12

what is emulsification?

Answer 12

dispersing one liquid into another through bonding interactions

Question 13

function of the small intestine

Answer 13

• The absorption of small molecules happens in our intestines.
• Sugar, fatty acids, glycerol and amino acids diffuse to move into the blood of our small intestine.

Question 14

function of the large intestine

Answer 14

• absorb water and a little bit of inorganic ions

Question 15

function of the rectum

Answer 15

waste from the large intestine is stored here as feces

Question 16

function of the anus

Answer 16

• feces is ejected out of our body (poop)
• the anal sphincters relax and food is ejected out of the body

Question 17

what is peristalsis?

Answer 17

a series of wave-like muscle contractions that move food through the digestive tract.

Question 18

what is amylase?

Answer 18

an enzyme found in saliva. it converts starch into glucose

Question 19

what is maltase?

Answer 19

an enzyme found in saliva. It catalyses the breakdown of maltose and similar sugars to form glucose.

Question 20

what is protease?

Answer 20

an enzyme found in the stomach, pancreas, and small intestine. It breaks down proteins and peptides.

Question 21

what is lipase?

Answer 21

an enzyme found in the pancreas, mouth, and stomach. It breaks down fats in food so they can be absorbed in the intestines

Question 22

what is bile?

Answer 22

• bile is a liquid that is produced in the liver and stored in the gall bladder.
• It breaks fats you eat into fatty acids, which your intestines can then absorb.
• it helps neutralise stomach acids and emulsify lipids

Question 23

adaptations of the small intestine

Answer 23

• Made of villi
• Villi helps increase the surface area so it can absorb more.