Chapter 6 - Nutrition & Digestion Flashcards
What is malnutrition?
It occurs in both under developed countries and developed countries.
In underdeveloped countries, it means undernutrition, where the diet may be neither balanced nor adequate.
In developed countries, it usually means the diet is more than adequate just not balanced.
What is the ideal diet?
A balanced diet includes carbohydrates, lipids, proteins, vitamins, mineral ions and dietary fibre. Sufficient water is also needed.
What are carbohydrates made up of?
Carbon, hydrogen and oxygen.
What are carbohydrates used for?
They provide the main source of energy for immediate use.
Can our bodies manufacture carbohydrates?
No, so we need to get them from plants and animals.
How are excess carbohydrates stored?
As glycogen in the liver and muscles.
As fat under the skin.
How do plants synthesis carbohydrates?
Photosynthesis.
There are 2 types of carbohydrates. State them below.
Sugars and starch.
What is glucose used for?
It’s a form of transport in the body.
Where do we find fructose mainly?
Fruit and honey.
What is sucrose?
Common household sugar.
Formed with fructose and glucose.
Where do we find lactose?
Occurs naturally in humans and cow’s milk.
How is starch used in plants?
It stores food in plant seed.
Unripe fruit contains starch which is converted into sugar when it ripens.
There are 2 main types of starch. Name them.
Cellulose, which is the major component in plant walls. Giving strength and rigidity to the plant.
Pectin which is present in apples and turnips.
Mention a couple of food products which are rich in carbohydrates.
Potatoes, pasta and wholewheat bread.
What are proteins made up of?
Carbon, hydrogen, oxygen and nitrogen.
Sometimes sulphur and phosphorus.
Proteins are long chains of what?
Amino acids.
Forming dipeptides and polypeptides.
How many amino acids are there?
There are 20 different amino acids.
There are 2 kinds of amino acids. State them below.
Non-essential are amino acids that can be changed into other forms within the body.
Essential are the 8 amino acids that cannot be formed in this way, and have to be taken in. Eg: Lysine.
What are proteins functions?
For growth and repair of muscle, skin tissue and bone.
To produce hormones, enzymes and antibodies.
To give energy.
For making haemoglobin.
Mention a few food products which are rich in protein.
Cheese, rice, eggs and chicken.
What are lipids made up of?
Carbon, hydrogen and oxygen.
What are lipids composed of?
1 glycerol + 3 fatty acids.
What unique property do lipids possess?
They are insoluble in water.
But soluble in organic solvents.
What are some good food sources for lipids?
Butter, cheese and meat.
What are lipids functions within the body?
They provided a lot of energy.
Component of cell membrane.
Form fatty tissues under the skin acting as insulator to keep warm.
Stored as fat around vital organs. Eg: kidney to protect them.
Acts as a solvent for important fat-soluble vitamins such as A, D, E, K.
One of the tests for lipids is the spot test. Explain it.
Oil leaves a permanent translucent spot on filter paper.
What are vitamins properties in general?
Although they have no energy value, they are essential in small amounts for good health.
Excessive amounts may be harmful.
Which vitamins are water soluble?
Vitamin B & C
Which vitamins are fat soluble?
Vitamins A, D, E and K
What does vitamin A provide for the body? Also where can it be found?
It is required for good vision; healthy hair, skin and nails.
You can find it in egg yolk, milk, cheese, carrots and green vegetable.
A deficiency in vitamin A, can cause what?
Night blindness,
What is vitamin C required for? Where can it be found?
It is required for binding of the cells and to maintain fitness.
It can be found is fresh fruits and green vegetables.
What can a deficiency in vitamin C lead to?
Scurvy
What is vitamin D required for? Where can it be found?
It is required for the uptake of calcium and phosphorus. Also for healthy teeth and bones.
Can be found in cod liver oil and egg yolk.
What can a deficiency in vitamin D cause?
Rickets.
Why are minerals important?
They are important for the health of living organism since they regulate body metabolism and are necessary for construction certain tissues.
Included Ca, S, K, Na, Mg, Fe, I.
What is calcium and phosphorus function and where can it be found?
It’s needed for making bones and teeth, also important for blood clotting and muscle contractions.
Found in cheese, milk and vegetables.
What does a deficiency in calcium and phosphorus lead to?
Rickets.
Why is sodium important for the body, and where can it be found?
It’s present in extra cellular fluid and it regulates it.
Found in salt and many food.
What does a deficiency in sodium lead to?
Cramps.
Why is iodine important and where can we find food rich in this substance?
Needed to synthesise hormones of the thyroid gland.
Found in sea food, drinking water.
What does a deficiency in iodine cause?
Goitre.
What is fluorine found in? Also, why is it important?
It builds a layer above the enamel.
Found in water and toothpaste.
What can an insubstantial amount of fluorine lead to?
It can lead to tooth decay.
Why is magnesium important?
It’s needed for metabolism and is found in most food.