digestion

Question 1

7 components for a healthy diet

Answer 1

carbohydrates, fibre, lipids, water, minerals, proteins and vitamins

Question 2

role and deficiency disease of iron

Answer 2

• forms part of haemoglobin

- anaemia

Question 3

role and deficiency of calcium

Answer 3

• needed to form teeth and bones

- rickets

Question 4

role and deficiency of vitamin A

Answer 4

• chemical in the retina, protects the surface of the eye

- night blindness

Question 5

role and deficiency of vitamin C

Answer 5

• needed for cells and tissues to stick together

- scurvy

Question 6

role and deficiency of vitamin D

Answer 6

• needed to absorb calcium

- rickets

Question 7

ingestion

Answer 7

taking food in through the mouth and swallowing

Question 8

digestion

Answer 8

breaking down large insoluble molecules into smaller more soluble molecules

Question 9

absorption

Answer 9

movement of smaller soluble molecules into the blood

Question 10

egestion

Answer 10

passing out undigested food through the anus

Question 11

assimilation

Answer 11

building larger molecules from the smaller ones in all cells

Question 12

mechanical digestion

Answer 12

food is broken down by chewing

Question 13

chemical digestion

Answer 13

saliva is released into the mouth by salivary glands and contains the enzyme amylase

Question 14

amylase

Answer 14

• made in the pancreas and the salivary glands

- breaks down starch into maltose

Question 15

peristalsis

Answer 15

wave like contractions that move food through the digestive tract

Question 16

pepsin

Answer 16

• secreted from the stomach walls

- breaks down protein to peptides

Question 17

trypsin

Answer 17

• made in the pancreas, secreted to the duodenum

- breaks down proteins to peptides

Question 18

lipase

Answer 18

• made in the pancreas, secreted into the duodenum

- breaks down lipids to three fatty acids and glycerol

Question 19

maltase

Answer 19

• secreted from the duodenum wall

- breaks down maltose to glucose

Question 20

protease

Answer 20

• secreted from the duodenum wall

- breaks down peptides to amino acids

Question 21

functions of bile

Answer 21

• neutralises the stomach acid

- emulsifies lipids, breaks larger droplets into smaller droplets

Question 22

where is bile made and stored

Answer 22

• made by the liver

- stored in the gall bladder

Question 23

how is the small intestine adapted to absorb molecules

Answer 23

• micro-villi increase the SA
• short diffusion distance
• high concentration gradient

Question 24

describe the experiment that investigates the energy content of a food sample

Answer 24

• measure out 25cm3 of water
• record initial temperature
• record and measure mass of food
• light the food with a bunsen and hold under test tube
• keep re lighting until it cannot be lit anymore
• take final temp of water
• calculate energy content with equation
  energy = mass of water x 4.2 x temperature increase