Section 2 - Human Nuturition Flashcards Preview

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Flashcards in Section 2 - Human Nuturition Deck (37)
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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 - 



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 .......




The digestive enzyme ....... converts maltose into .......




The digestive enzyme ....... converts proteins into .......


amino acids


The digestive enzyme ....... converts lipids into ....... and ........


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


What is A and what is its purpose (3)

- Mouth

- Salivary glands produce amylase enzymes in the saliva

- Teeth break down food mechanically


What is B and what is its purpose (2)

- Oesphoagus

- Muscular tube that connects the mouth and stomach



What is C and what is its purpose (2)

- Liver

- Where bile is produced


What is D and what is its purpose (4)

- Stomach

- Pummels food with its muscular walls

- Produces protease enzyme, pepsin

- Produces HCL; 

to kill bacteria

to give the right pH for the protease enzyme to work


What is E and what is its purpose (3)

- Pancreas

- Produces protease, amylase and lipase enzymes

- It releases these into the small intestine 


What is F and what is its purpose (2)

- Large intestine

- Where excess water is absorbed from the food