8.4 Organisms Flashcards
Nutrient
An essential substance provided by food that your body needs to survive
What are the six (+1) types of nutrients?
- Carbohydrates
- Lipids
- Proteins
- Vitamins
- Minerals
- Water
- Fibre (not a nutrient, but important)
What is the job of carbohydrates?
To provide energy
What are the 2 types of carbohydrates?
- Simple (sugars)
- Complex (starch)
Where are simple carbohydrates found?
In sugar and fruit, quick source of energy
Where are complex carbohydrates found?
Bread and pasta, energy released more slowly because they have to be broken down
Why are proteins needed?
To repair body tissues and make new cells
Where are lipids found?
It fast and oils, including butter
What are the 3 important jobs of lipids?
- Provide store of energy
- Keep you warm
- Protect organs like kidneys and heart from damage
Do you need a large amount of vitamins and minerals?
No, only needed in small amounts
What is vitamin A good for?
Eyesight
What are vitamin D and calcium (mineral) used for?
To maintain healthy bones and teeth
Why is iron important?
Important for making red blood cells
Cells are made up of ….% water
70
How does the body lose water?
In sweat, tears 😭, urine and faeces
How much water should you drink?
Over a litre a day
What is dietary fibre?
Parts of plants that the body can’t break down
Why is dietary fibre important?
Keeps food moving through the gut, preventing constipation
Balanced diet
Eating food containing the right nutrients in the right amounts
How do you test for starch?
Add a few drops of iodine to the food solution
What is the colour change in a food solution if it has starch?
Yellow/orange —> Dark blue/black
How do you test for lipids?
Add a few drops of ethanol to food solution
What happens to the food solution if it has lipids?
Clear —> white layer on top
How to you test for sugar (glucose)?
- Add a few drops of Benedict’s solution to the food solution
- Heat the test tube in a water bath
What will the solution look like if it has glucose?
Blue, Green/ yellow, Orange/red, brick red
Negative, Traces of glucose, Moderate amount, Large amount of glucose
How do you test for protein?
Add a few drops of copper sulfate solution and sodium hydroxide solution to your food solution
Explain why a pregnant woman needs more energy than a female office worker
The pregnant woman will require extra energy for the growth of the foetus
A food scientist carried out an experiment to measure how long it takes enzymes to digest
starchy food.
They did this by adding an enzyme to a starch solution in a boiling tube.
The scientist also placed 7 drops of iodine onto a white tile.
Every 30 seconds, a drop was taken out of the boiling tube and mixed with one of the drops of
iodine. The scientist then measured the intensity of light (the amount of light that passes through
the solution) transmitted through the mixture.
This was repeated with a new drop of iodine every 30 seconds for 3 minutes.
Explain why iodine was used in this test
- Iodine is the indicator of the presence of starch
- When iodine is added to a starch solution, it turns from a yellow/orange colour to a black/blue colour
- The iodine and starch solution would be very dark at the start but then lightening in colour (allowing more light to pass) as the enzyme breaks down the starch
What is iron important for?
Making red blood cells
What is vitamin A good for?
Vitamin A is good for eyesight
Give an example of a food with lipids
Butter
What are the two types of carbohydrates?
- Simple carbohydrates (sugar)
- Complex carbohydrates (starch)
What is protein needed for?
- Repair body tissues
- Make new cells
What is the job of carbohydrates?
To provide energy
Complete the sentence:
Cells are made up of ____% water
70
What do vitamin d and calcium do?
Maintain healthy bones
Give the definition of a nutrient
An essential substance provided by food that your body needs to survive
What are digestive enzymes?
Chemicals that break down large insoluble molecules into smaller soluble molecules.
What does carbohydrase (amylase) break down?
Carbohydrates (starch) into glucose (small sugar).
What does protease break down?
Proteins into amino acids.
How are fats broken down?
1) Bile breaks down fats so they have a larger surface area (emulsification).
2) Lipase breaks the fats down further into glycerol and fatty acids.
Where are bacteria/gut bacteria found?
In your large intestine.
What do gut bacteria/bacteria do?
-They feed on fibre in your diet, breaking down food.
-They make vitamins.
What foods contain bacteria?
Probiotic foods like yogurt.
