Human nutrition

Question 1

What does iodine solution test for?

Answer 1

starch

Question 2

If starch is present, what colour change will happen in the solution

Answer 2

goes from orange to blue/black

Question 3

How to test for glucose

Answer 3

5cm3 of sample in test tube
Add around 10 drops Benedict’s solution
Heat in water bath for 5 mins at 75 degrees

Question 4

Positive result of the test for glucose

Answer 4

solution turns blue to green/ yellow/ brick red
(red is the highest concentration of glucose)

Question 5

What is the name of the test for lipids

Answer 5

the emulsion test

Question 6

how to test for lipids

Answer 6

add 2cm3 ethanol to food sample in test tube
shake the test tube aggressively

Question 7

colour change if lipids are present in the emulsion test

Answer 7

turns from colourless to cloudy white

Question 8

what does biuret solution test for

Answer 8

protiens

Question 9

colour change when protiens are present in the biuret test

Answer 9

solution turns from blue to lilac/purple

Question 10

what is the main type of carbohydrate

Answer 10

starch

Question 11

what is starch broken down by and what is it broken into

Answer 11

broken down by amylase
broken into smaller sugars called maltose

Question 12

where is amylase made in the body

Answer 12

pancreas, small intestine, salivary glands

Question 13

what are proteins broken down by, and what are they broken into

Answer 13

broken down by protease enzymes
into amino acids

Question 14

where are proteases made

Answer 14

stomach (pepsin)
small intestine
pancreas

Question 15

what are fats broken down by and what are they broken into

Answer 15

broken down by lipases into glycerol and fatty acids

Question 16

where are lipases made

Answer 16

small intestine
pancreas

Question 17

what is starch a polymer of

Answer 17

glucose

Question 18

how are maltose molecules broken down into glucose

Answer 18

by maltase

Question 19

examples of protease enzymes

Answer 19

pepsin
trypsin

Question 20

what is bile

Answer 20

a yellow-greenish liquid released from the gall bladder that helps with lipid digestion

Question 21

how does bile help with digestion of lipids

Answer 21

it emulsifies the lipids which increases the surface area for lipase enzymes to break them down

Question 22

what type of digestion is chewing

Answer 22

physical

Question 23

what does the stomach do during physical digestion

Answer 23

contracts muscular walls
produces pepsin to break down protein
produces hydrochloric acid which kills bacteria and creates right environment for pepsin

Question 24

where does digested food get absorbed into the bloodstream

Answer 24

small intestine

Question 25

which organ creates the most digestive enzymes

Answer 25

pancreas

Question 26

what does the gall bladder release into the small intestine

Answer 26

bile

Question 27

what are the two main roles of bile

Answer 27

neutralises acid from the stomach
emulsifying fats - gives the fats a bigger surface area for the digestive enzymes to work on

Question 28

how does the small intestines structure help digested food to be absorbed into the bloodstream

Answer 28

villi - increases surface area, digested food can be absorbed into bloodstream more quickly
villi have a single layer of surface cells - nutrients only diffuse a short distance

Question 29

what is released into the small intestine to mix with digested foods

Answer 29

pancreatic juices
bile

Question 30

what are the two main functions of the digestive system

Answer 30

digestion
absorption

Question 31

what is digestion

Answer 31

process of breaking down large food molecules into smaller molecules

Question 32

how do teeth breaking food down into smaller pieces help digestion

Answer 32

makes food easier to swallow
increases the surface area for enzymes to act on

Question 33

which enzyme is in saliva and what does it do

Answer 33

amylase - breaks down starch into maltose

Question 34

what carries food from the mouth to the stomach

Answer 34

oesophagus