Nutrition Flashcards
Describe test for starch
Iodine solution: turn blue/black
Describe test for reducing sugar
Benedict solution:
- Beaker filled with boiling water placed on heat proof mat
- Same volume of Benedicts solution to the food extract- put in hot water
Positive result: red/orange
Describe test for fat
- Add ethanol to the extract of food in a clean test tube
- Bunk over the open and shake up the content
- Add distilled water half full
- Positive test: white emulsion, cloudy white
Importance of vitamin C and D
- tissue repair(bleeding gums, resistance to disease
- strengthen bones and teeth.
List the principal sources and importance of mineral salts(iron and calcium only)
-Iron(liver,meat): transport of oxygen
Calcium(milk,fish):strengthen bones and teeth
Describe the deficiency symptoms if vitamins C and D
- Bleeding gums
- Soft bones
Describe the deficiency symptoms for mineral salts(iron and calcium)
- Weak, brittle bones and teeth
- Tiredness,lack of energy
Describe the use of microorganisms in the manufacture of yoghurt
- The bacteria Lactobacillus break down the sugar lactose to form lactic acid.
- Lactic acid lowers the pH of yogurt, which helps to preserve and denatures milk protein
Define photosynthesis
The fundamental process by which plants manufacture carbohydrates from raw materials using energy from light
Word equation for photosynthesis
carbon dioxide+water - glucose+oxygen
Why chlorophyll traps light energy and converts it into chemical energy?
For the formation of carbohydrates and their subsequent storage
- From water and carbon dioxide, the energy split water into hydrogen ions which reduce carbon dioxide into carbohydrates.
List the use of glucose as a by product of photosynthesis
- Respiration in leaf
- Some of glucose changed into starch/stored in leaves in future
- Used to make cellulose, make cell walls
- Converted to sucrose- transported to phloem
State the effect of varying light intensity
Rate increase if light increases
Describe test for protein
5 to 6 drops to the food extract
Positive test: purple/violet
Describe the internal features of the leaf for photosynthesis
- Chloroplast in the palisade mesophyll are near the upper surface of the leaf the maximize absorption of light
- Stomata open to allow carbon dioxide diffuse in the leaf
Why leaves are thin?
So carbon dioxide does not have to diffuse far from the atmosphere to the cell of palisade and spongy mesophyll.
Stomata are opened and closed by what?
Guard cell
Describe the importance of nitrate ions for protein synthesis.
To make amino acids which are used to make proteins
Describe the importance of magnesium ions for chlorophyll synthesis
Absorbed by plants and used to make chlorophyll.
Explain the effects of nitrate ion efficiency on plant growth
Helps make amino acids which make protein, lack of this ion, plant will show poor growth
Explain the effects of magnesium ion efficiency on plant growth
Used to make chlorophyll, lack of this ion will make yellow leaves.
What is nitrogen-containing fertilizer?
Is a compound that is added to plant to stimulate chloroplast(growth) in plant for photosynthesis
Dangers of overuse the nitrogen fertilizers.
-Harmful for agriculture, plasmolysis take place, water passes from plants to soil- wilting of the plants
