Section 2 - Human Nuturition Flashcards
(37 cards)
What elements do carbohydrate molecules contain (3)
- Hydrogen - Oxygen - Carbon
Starch and glucose are large, …… carbohydrates, made up of many smaller units, joined together in a …. ……
- complex - long chain
What are proteins made up of (2)
- Amino Acids
- Long chains
What elements do amino acids contain (4)
- Carbon - Nitrogen - Hydrogen - Oxygen
What are lipids made up of (2)
- Fatty acids - Glycerol
What elements do lipids contain (3)
- Carbon - Hydrogen - Oxygen
Describe how to test for glucose (5)
- Benedict’s test
- Add blue Benedict’s reagent to a sample and heat it
- Make sure the solution doesn’t boil
- If glucose is present, it will forma a coloured precipitate
- The higher the conc of glucose, the further the colour change goes (use to compare)
For the Benedict’s test, what are the colours for varying conc’s of glucose (3)
None -
Low -
High
Describe how to test for starch (2)
- Add iodine solution
- If starch is present, sample changes from brown/orange to a dark, blue/black colour
What are the 5 essential nutrients (5)
- Carbs
- Protein
- Fats
- Vitamins & Minerals
- Water
+ Fibre
What is the function of Vitamin A, C and D and what are they found in (6)
Vitamin A - Liver - Improve vision, keep your skin and hair healthy
Vitamin C - Oranges - Prevent scurvy
Vitamin D - Eggs - Needed for calcium absorption
What 2 mineral ions de we need, what are their functions and what can we find them in (6)
Calcium - Milk, cheese - make bones and teeth
Iron - Red meat - needed to make haemoglobin for healthy blood
What is dietary fibre’s function and what is it found in (2)
- Aids the movement of food through the gut
- Wholemeal bread
Describe an experiment to show how much energy is in food (9)
- Find a food that burn’s easily; a peanut
- Weigh a small amount of the food and then skewer it with a mounted needle
- Add 25cm3 of water to a boiling tube, and measure its temperature
- Set fire to the food using a bunsen burner
- Hold the burning food under the boiling tube until it goes out
- Relight and hold again, until no longer possible
- Measure the temperature of the water
Use : 25 x temp change x 4.2 = energy in food
Use : energy/mass = energy per gram of food (J/g)
Describe a way to make the energy from food practical more accurate (2)
- Insulate the boiling tube with foil
- Minimises heat loss and keeps more energy in the water
Why are digestive enzymes needed in the body (3)
- Digestive enzymes break down big insoluble molecules into smaller soluble ones
- Starch, proteins and fats are too big to pass through the walls of the digestive system
- Digestive enzymes allow starch, proteins and fats to be soluble and pass through the walls of the digestive system to be digested
The digestive enzyme ……. converts starch into …….
Amylase
Maltose
The digestive enzyme ……. converts maltose into …….
maltase
glucose
The digestive enzyme ……. converts proteins into …….
protease
amino acids
The digestive enzyme ……. converts lipids into ……. and ……..
Lipase
Fatty acids and glycerol
Where is bile produced, stored and released into (3)
Produced - liver
Stored - gall bladder
Released into small intestine
What does bile do (3)
- Bile neutralises hyrdochloric acid in the stomach
- Allowing enzymes in the small intenstine to work properly
- Bile emulsifies fats, making digestion faster as there is a bigger surface area of fat
The ………… …….. is another name for the gut (1)
alimentary canal
Label all 10 partS (10)
A - Mouth
B - Oesophagus
C - Liver
D - Stomach
E - Pancreas
F - Large Intestine
G - Small Intestine
H - Appendix
I - Anus
J - Gall bladder
