Food Flashcards
(41 cards)
1
Q
What is a balanced diet?
A
- A diet that provides enough of these substances and in the correct proportions to keep you healthy.
2
Q
What are carbohydrates used for and how is it released?
A
- They are the body’s main fuel for supplying cells with energy.
- Cells release this energy by oxidising a sugar called glucose.
3
Q
What is starch?
A
- It is a large, insolube molecule.
- It is a polymer of glucose (made up of long chains of hundreds of lgucose molecules joined together)
4
Q
What is the similar carbohydrate of starch found in animal cells?
A
- Glycogen
5
Q
What is another polymer of glucose that humans cannot digest?
A
- Cellulose
- Makes up plant cell walls
6
Q
What do humans often use cellulose for?
A
- Forms dietary fibre
- Gives muscles of gut something to push against as the food is moved through the intestine.
- Keeps the gut contetns moving, avoiding constipationa nd helping to prevent serious diseases of the intestine.
7
Q
What are single sugars called and what are some examples?
A
- Monosaccharides
- Glucose and fructose
8
Q
What are disaccharides?
A
- Two monosaccharides (glucose and fructose) joined together
- E.g. Sucrose
9
Q
What are polysaccharides?
A
- Polymers of sugars
- Such as starch and glycogen
10
Q
What are lipids needed for?
A
- Form an essential part of the structure of all cells
- Fat is deposited in certain parts of the body as a long-term store of energy.
11
Q
What does the fat layer under the skin act as?
A
- As insulation, reducing heat loss through the surface of body.
- Fat around organs to protect them from mechanical damage
12
Q
What are lipids made out from?
A
- A molecule of glycerol joined to three fatty acid molecules
13
Q
What is kwashiorkor?
A
- A protein-defiency disease
14
Q
What are proteins made up of?
A
- 20 different sub-units called amino acids
15
Q
What is the structure of a protein?
A
- The amino acids are linked together in chains, which are usually folded up or twisted into spirals, with cross-linls holding the chains together.
16
Q
What examples of proteins are there?
A
- Structural proteins, e.g. collagen and kertin in skin and nails
- Specific functions, e.g. enzymes and haemoglobin
17
Q
What is calcium used for in the body?
A
- Making teeth and bones
18
Q
What is phosphorus used for in the body?
A
- Making teeth and bones
- Part of many chemicals, e.g. DNA
19
Q
What is sodium used for in the body?
A
- In body fluids, e.g. blood
20
Q
What is chlorine used for in the body?
A
- In body fluids, e.g. blood
21
Q
What is magnesium used for in the body?
A
- Making bones
- Found inside cells
22
Q
What is iron used for in the body?
A
- Part of haemoglobin in red blood cells, helps carry oxygen
23
Q
What will people who don’t get enough of a mineral in their diet develop?
A
- Mineral deficieny disease
24
Q
What happens if a young child doesn’t consume the right amount of calcium every day?
A
- The bones will become deformed, rsulting in rickets.
25
What happens if a person doesn't get enough iron in their diet?
* They cannot make enough haemoglobin for their red blood cells.
* Causes anaemia, where you become tired and lack energy, becasue their blood doesn't carry enough oxygen.
26
What is the use in the body of vitamin A?
* Makes a chemical in the reetina
* Also protects the surface of the eye
27
What is the effect of a deficiency of vitamin A?
* Night blindness
* Damaged cornea of eye
28
What is the use in the body of vitamin B1?
* Helps with cell respiration
29
What is the effect of a deficiency of vitamin B1?
* Beri-beri
30
What is the use in the body of vitamin B2?
* Helps with cell respiration
31
What is the effect of a deficiency of vitamin B2?
* Poor growth
* Dry skin
32
What is the use in the body of vitamin B3?
* Helps with cell respiration
33
What is the effect of a deficiency of vitamin B3?
* Pellagra (dry red skin, poor growth,a nd digestive disorders)
34
What is the use of vitamin C in the body?
* Sticks together cells lining surfaces such as the mouth
35
What is the effect of a deficiency of vitamin C?
* Scurvy
36
What is the use in the body of vitamin D?
* Helps bones absorb calcium and phosphate
37
What is the effect of deficiency of vitamin D?
* Rickets, poor teeth
38
What is the test for starch?
* Place starch on a white, spotting tile.
* Add a drop of dilute iodine solution to the starch.
* The iodine should react witht he starch, forming a very dark blue or 'blue-black' colour.
39
What is the test for glucose?
* Add a small spatula of glucose in a test tube.
* Add a little water.
* Shake the tube to dissolve the glucose.
* Add several drops Benedict's solution to the tube, enough to coloru the mixture blue.
* A water bath is prepared by ahlf-filling a beaker with water and heating it.
* Place the test tube in the beaker and allow the water to boil.
* After a few seconds the clear blue solution shuld gradually change colour, forming a cloudy orange or 'brick red' precipitate.
40
What type of sugar will the test for glucose work with?
* Reducing sugars, e.g. fructose and lactose.
* Won't work with sucrose
41
What solution is reduce in the test for glucose and what is it reduced to?
* Copper (II) sulfate ------\> copper (I) oxide
