Food Flashcards
The need for food?
- A source of energy
2. For raw materials that are needed growth and repair tissue.
The elements of food?
carbon, hydrogen, nitrogen, oxygen, phosphorus and sulphur
What is a biomolecule?
Are chemicals that are made inside of a living.
What are the types of carbohydrates?
monosaccharides, disaccharides and polysaccharides .
What is a monosaccharide?
they are composed of a single unit. An example would be glucose and fructose
What is a disaccharide?
they are composed of two sugar unites. An example would be maltose.
What is a polysaccharide?
They are composed of many sugar units. They are insoluble and aren’t sweet tasting. Examples include starch, cellulose and glycogen.
What is the metabolic role of carbohydrates?
- Glucose is made in photosynthesis
2. Glucose releases energy in respiration
What is the structural role of carbohydrates?
Cellulose is used to form plant cell walls.
What is the test for carbohydrates?
reducing sugars = Benedict’s solution
starch = iodine
What are lipids?
It is made from carbon, hydrogen and oxygen
What is the difference between fats and oils at room temperature?
Fats are solid while oils are liquid at room temperature {20’C}
Structure of lipids?
Glycerol and three fatty acids = triglyceride
Structural role of lipids?
- store energy
- insulate
- form membranes
Metabolic role of lipids?
Lipids can be broken down in respiration to release energy.
What is phospholipids?
They are fat-like substances in which one of the fatty acids is replaced by a phosphate group.
What test is it for lipids?
Brown paper
Protein is made out of carbon, hydrogen and oxygen, what is missing?
Nitrogen.
What is the structure of protein and how many are there?
amino acids, 20
What is a fibrous protein?
They form long fibres and are strong and tough.
What’s an example of fibrous protein?
Keratin which is found in hair.
What is globular protein?
They form rounded shapes.
Give an example of globular protein.
Egg whites which is found in enzymes.
Give two examples of sources of protein
Beans and eggs
What is deamination?
It is when surplus amino acids are taken to the liver and converted to urea which is toxic waste product.
What is the metabolic role of proteins?
- Proteins are used as enzymes to control reactions
- Proteins also form antibodies to fight infections
- Some hormones are protein-based and are used to regulate body reactions.
What is the test for proteins?
Sodium hydroxide and the biuret test.
Name one water soluble vitamin and one fat soluble vitamin.
Vitamin C and vitamin D
What are the sources of vitamin C?
Fresh fruit such as oranges.
What is the metabolic role of vitamin C?
- The growth and maintenance of bones and teeth.
- Helping wounds to heal.
- Helping immune system to function
What is the deficiency of vitamin C?
Scurvy and the symptoms are poor healing of the skin.
What are the sources of vitamin D?
Egg yolk
What is the metabolic role of vitamin D?
Helps to absorb calcium from the intestine
What is the deficiency of vitamin D?
Rickets and in adults osteomalacia. The symptoms are weak, deformed bones that break easily.
What are the reasons of minerals?
- To form biomolecules
- To form rigid body structures
- To make soft body parts such as muscle
What is the source and use of a mineral in plants?
Magnesium, source = salts in the soil and the use is to help form chlorophyll
what is the source and use of a named animal mineral?
Iron, source= meat and the use is to help form haemoglobin
What is the reason for water?
- It is the liquid which all metabolic reactions take place.
- It provides the basis for transport systems in the organism
- It is the environment in which many organisms live.
What are the two metabolism reactions?
Anabolic reactions and catabolic reactions
What is an anabolic reaction?
It is energy that is taken in and used to convert small molecules to larger ones, for example, photosynthesis
What is a catabolic reaction?
It is larger molecules that are then broken down to smaller ones and energy is released, for example, respiration.
What is the difference between triglyceride and phospholipid?
Triglyceride has one glycerol and three fatty acids, while phospholipid has one glycerol, two fatty acids and phosphate.
What are the three trace elements?
iron, copper and zinc
