Digestion

Question 0

Oesophagus

Answer 0

carries food from mouth to stomach, adapted for transport, thick muscular wall

Question 1

Why do glands produce enzymes?

Answer 1

To break down large molecules into small ones ready for absorption

Question 2

Stomach

Answer 2

muscular sac with inner layer which produces enzymes, stores and digests food, glands produce enzymes which digest protein, other glands produce mucus which prevents stomach being digested by its own enzymes

Question 3

Small intestine

Answer 3

long muscular tube, digested more by enzymes secreted by wall, inner walls fold into villi, large surface area, microvilli on epithelial cells of villi provide even more sa so products of digestion can be absorbed into bloodstream

Question 4

Large intestine

Answer 4

absorbs water, most water absorbed back comes from gland secretions, food becomes drier and thicker, forming faeces

Question 5

Rectum

Answer 5

faeces stored here before being removed by egestion via the anus

Question 6

Salivary glands

Answer 6

pass secretions via a duct into the mouth, secretions contain amylase which breaks down starch into maltose

Question 7

Pancreas

Answer 7

large gland which secretes pancreatic juice, containing protease to break down the proteins, lipase to digest lipids and amylase to digest starch

Question 8

What is Physical digestion?

Answer 8

1. Teeth chew to increase surface area for chemical digestion and makes it possible to ingest food
2. Pummelled by the stomach walls which physically breaks it up

Question 9

What is chemical digestion?

Answer 9

Breaking down large, insoluble molecules into small, soluble ones, carried out by enzymes

Question 10

What is hydrolysis?

Answer 10

Hydrolysis is the splitting up of molecules by adding water to the chemical bonds that hold them together

Question 11

What is the general term for enzymes that work by hydrolysis?

Answer 11

Hydrolases

Question 12

How does hydrolysis work?

Answer 12

One enzyme splits a large molecule into sections, and these sections are the hydrolysed into smaller molecules by one or more additional enzymes

Question 13

Name 3 different types of digestive enzymes

Answer 13

Carbohydrases break down carbohydrates, ultimately to monosaccharides
Lipases break down lipids into glycerol and fatty acids
Proteases break down proteins, ultimately to amino acids

Question 14

What is assimilation?

Answer 14

The assimilated small molecules build up in different parts of the body to form larger molecules which are incorporated into body tissues and/ or used in processes

Question 15

What is digestion?

Answer 15

Digestions is the process in which large molecules are hydrolysed by enzymes into small molecules which can be absorbed and assimiliated