Biology: Nutrition

Question 1

Chemical elements that make up carbohydrates, fats and proteins.

Answer 1

Carbohydrates: Carbon, Hydrogen, Oxygen
Fats: Carbon, Hydrogen, Oxygen
Proteins: Carbon, Hydrogen, Oxygen, Nitrogen

Question 2

Describe the structure of large molecules

made from smaller basic units, i.e…

Answer 2

…
• simple sugars to starch and glycogen
• amino acids to proteins
•fatty acids and glycerol to fats and oils.

Question 3

Test for Starch.

Answer 3

Add a few drops of iodine solution. Brown to Blue-Black if starch is present.

Question 4

Test for Reducing Sugars.

Answer 4

Add an equal amount of Benedict’s Solution as the volume of solution you are testing. Stir and observe any colour changes. If none, heat gently and look for colour changes. If no colour changes, reducing sugars are not present.
Positive: Blue->green/yellow/orange/red

Question 5

Test for Protein.

Answer 5

Add biuret reagent to the solution. Blue to Purple if proteins are present.

Question 6

Test for Fats.

Answer 6

Solid:
Crush food sample and put in test tube. Add ethanol to 2-3cm above the sample. Allow to settle. Put ethanol into another test tube and add water. Observe
Liquid:
Add a few drops of liquid sample. Add 2 cm3 ethanol and shake it thoroughly. Add 2 cm3 of deionized water. Observe
Positive indicator is a white precipitate

Question 7

Principle Sources/Importance of Carbohydrates

Answer 7

food such as rice, wheat, cereal, bread.

Essential for Respiration; broken down to release energy for respiration

Question 8

Principle Sources/Importance of Fats

Answer 8

found in oil, butter, margarine etc

Insulate the body, serve as store of energy

Question 9

Principle Sources/Importance of Proteins

Answer 9

found in meats, beans, lentils etc

Form our muscles, enzymes, skin, hair etc

Question 10

Principle Sources/Importance of Vitamin C

Answer 10

found in many fresh fruits

Required for the development/maintenance of scar tissues, blood vessels, cartilage. Contributes to healthy teeth/gums.

Question 11

Principle Sources/Importance of Vitamin D

Answer 11

most is formed under our skin after contact with sunlight

Maintenance of bone health, regulates the flow of calcium into the blood stream. Promotes absorption of calcium.

Question 12

Principle Sources/Importance of Calcium

Answer 12

found in milk, dairy foods etc
Supports bone structure and hardness. Required for certain muscles to move and for nerves to carry messages between the brain and every body part.

Question 13

Principle Sources/Importance of Iron

Answer 13

found in liver, meat, beans, nuts, dried fruit, wholegrains (e.g brown rice), fortified breakfast cereals, sorbean flour and dark-green leafy vegetables.
Needed to form haemoglobin to carry oxygen

Question 14

Principle Sources/Importance of Fibre(Roughage)

Answer 14

found in wholemeal bread, bran, cereals, nuts and seeds

Adds bulk in food so intestines can push it through the alimentary canal.

Question 15

Deficiency symptoms of Vitamin C

Answer 15

Scurvy

Question 16

Deficiency symptoms of Vitamin D

Answer 16

Rickets

Question 17

Deficiency of Calcium

Answer 17

Memory loss, musle spasms, numbness and tingling in the hands, feet and face, depression, hallucinations and organ failure.

Question 18

Deficiency of Iron

Answer 18

Fatigue, decreased work and school performance, slow cognitive and social development in childhood, difficulty in regulating body temperature, decreased immune function and glossitis.
Anemia.

Question 19

Define photosynthesis as the fundamental process by which plants manufacture carbohydrates from raw materials using energy from light

Answer 19

Fundamental process by which plants manufacture carbohydrates from raw materials using energy from light.

Question 20

Explain that chlorophyll traps light energy and converts it into chemical energy for the formation of carbohydrates and their subsequent storage.

Answer 20

Chlorophyll traps light energy and converts it into chemical energy for the formation of carbohydrates and their subsequent storage.

Question 21

State the balanced equation for photosynthesis in symbols

Answer 21

6CO2 + 6H2O -light/chlorophyll-> C6H12O6 + 6O2

Question 22

State the word equation for the production of simple sugars and oxygen

Answer 22

Carbon Dioxide + Water -> Glucose + Oxygen

Question 23

Investigate and state the effect of varying light intensity on the rate of photosynthesis (e.g. in submerged aquatic plants).

Answer 23

Increase of rate of photosynthesis

Question 24

Investigate the necessity for chlorophyll, light and carbon dioxide for photosynthesis, using appropriate controls.

Answer 24

YOU NEED THEM ALL!!! [leave in dark, use white leaf, soda lime]

Question 25

Describe the intake of carbon dioxide and water by plants.

Answer 25

Carbon Dioxide is taken through the stomata. Water is taken in through the root hair cells.

Question 26

State what is meant by the term balanced diet and describe a balanced diet related to age, sex and activity of an individual.

Answer 26

A balanced diet is a diet that consists of the correct proportions of each nutrient. It should contain all the nutrients. A balanced diet is slightly different for every person as our energy requirements differ based on our age, sex and activity.

Question 27

5 Stages of Digestion

Answer 27

Ingestion; getting food into our alimentary canal; mouth
Digestion; breaking down of food into smaller bits and then into smaller molecules; mouth, small intestine, stomach
Assimilation; nutrients in our food being used by our cells; cells
Absorption; nutrients from our food passing from our alimentary canal into our bloodstream; small intestine
Waste elimination; removal of waste materials from our bodies; rectum/anus

Question 28

Describe the effects of malnutrition in relation to starvation, coronary heart disease, constipation and obesity.

Answer 28

Starvation is caused by consumption of not enough food. Effects of this could be intense weight loss, organ damage or even death.
Coronary Heart Disease is when cholesterol sticks to the walls of your coronary arteries, causing them to not be able to function properly. This can sometimes forms blood clots which cut off or limit supply of blood and therefore, oxygen, leading to an ischaemic heart attack.
Constipation is when you are unable to defecate. This is caused by lack of fibre meaning intestines aren’t able to push food down the alimentary canal.
Obesity is caused by consumption of too much food. This can lead to multiple diseases including diabetes, strokes and difficulty breathing.

Question 29

Define digestion as the break down of large, insoluble food molecules into small, water-soluble molecules using mechanical and chemical processes

Answer 29

The break down of large, insoluble food molecules into small, water-soluble molecules using mechanical and chemical processes

Question 30

Identify the types of human teeth and describe their structure and functions.

Answer 30

Incisors; biting and cutting
Canines; ripping and tearing
Molars/Premolars; chewing and grinding

Question 31

State the causes of dental decay and describe the proper care of teeth.

Answer 31

Plaque buildup, not brushing, eating sugar, not enough saliva/flourine.
Brushing teeth/using mouthwash, not smoking, well-balanced diet.

Question 32

Define absorption as movement of digested food molecules through the wall of the intestine into the blood.

Answer 32

movement of digested food molecules through the wall of the intestine into the blood

Question 33

Alimentary Canal

Answer 33

Google Please