|
|
Created by eimearkelly3
over 12 years ago
|
|
| Question | Answer |
| Nutrition | The way in which an organsim obtains and uses its food. |
| Nutrient | Any substance that is important in sustaining life. They are chemical substances present in food that are used by organisms to maintain metabolism and the continuity of life. |
| nutrients are used | as a source of energy to make chemicals needed for cell and metabolic reactions the raw materials for growth and repair of an organism. |
| Biomolecules/biochemicals | Substances made by living things that have important metabolic roles. They are organic compunds that contain carbon, hydrogen, and other elements. (carbohydrates, lipids, proteins). |
| Compounds made from carbon | Organic compounds |
| Organic compounds are composed of | Carbon |
| Common elements of food | Carbon, hydrogen, oxygen, nitrogen, phosphorous, sulfur |
| Elements present as dissolved salts in food | Sodium, magnesium, chlorine, calcium, potassium |
| Trace elements in food | Zinc, copper, iron |
| The build up of simple molecules to complex molecules requiring energy | protein synthesis/photosynthesis (ANABOLISM) |
| The break down of complex molecules to simple molecules resulting in the release of energy | digestion/respiration (CATABOLISM) |
| Test for reducing sugars | Benedict's solution (requires heat) blue--> brick red |
| Test for starch | Iodine red-yellow --> blue-black |
| to test for protein | biuret solution (copper sulfate + sodium hydroxide) blue --> lilac |
| to test for fat | brown paper translucent stain |
| Carbohydrates are composed of | Carbon, hydrogen, and oxygen |
| sources of carbohydrates | rice, pasta, potatoes, bread |
| single sugar units | monosaccharides |
| 2 monosaccharides | disaccharides |
| many monosaccharides | polysaccharide |
| monosaccharides | single sugar units sweet & soluble energy providers e.g. pentoses - ribose, deoxyribose hexoses - glucose, fructose, galactose |
| disaccharides | 2 monosaccharides sweet & soluble energy providers e.g. sucrose (table sugar glucose + fructose) maltose (germinating seeds glucose + glucose) lactose (milk glucose + galactose) |
| sucrose (table sugar) | fructose + glucose |
| maltose (germinating seeds) | glucose + glucose |
| lactose (milk) | glucose + galactose |
| polysaccharides | many monosaccharides linked together not sweet & insoluble food storage / structural support e.g. starch (amylose) chitin cellulose glycogen |
| Starch | food storage in plants branched and unbranched chains of glucose molecules easily digested rice, potatoes, flour, pasta, bread |
| Cellulose | Structural carbohydrate in plants (cell wall) long chains of glucose molecules bonded together more cross bonding than starch, less easily digested --> fibre |
| Chitin | strong polysaccharide in the exoskeleton of arthropods (crabs, beetles, lobsters, cell walls of fungi) structural support |
| Glycogen | polysaccharide stored by animals many glucose molecules, more branched than starch stored predominantly in muscle and liver cells |
| lipids | fats + oils |
| Elements in lipids | Carbon, hydrogen, oxygen |
| Fats | Solid at room temperature |
| Oils | Liquid at room temperature |
| Sources | Milk, butter, cheese, meat plant oils, margarine |
|
Image:
examtime_1 (image/jpg)
|
Triglyceride |
|
Image:
examtime_1 (image/jpg)
|
Phospholipid |
| Triglyceride | Fat and oil energy reserves |
| Phospholipid | Cell membranes |
| structural role of lipids | phospholipids --> cell membranes under the skin --> heat insulation and energy store (adipose tissue) protective layer around the internal organs e.g. kidneys protective wax cuticle on the outside of plants e.g. holly |
| metabolic role of lipids | energy storage --> more than 2x the energy of the same mass of protein or carbohydrate energy source --> released during respiration storage of fat soluble vitamins e.g. Vitamin D some lipids act as hormones e.g. oestrogen |
| Elements in proteins | Carbon, hydrogen, oxygen, nitrogen (sometimes phosphorous or sulfur) |
| Proteins are composed of | amino acids |
| Link between amino acids | Peptide bond |
| Shape of a protein | Three-dimensional, functional shape |
| Small number of amino acids | Peptide |
| 20 or more amino acids | Polypeptide |
| Long polypeptide (more than 200 amino acids) | Protein |
| Fibrous proteins | Long chains in parallel form (little / no folding) strong & tough e.g. keratin, collagen, myosin |
| Globular proteins | Tightly folded amino acid chains giving a spherical shape e.g. enzymes |
| Protein synthesis takes place in the | Ribosomes |
| Sources of proteins | Meat, fish, eggs, nuts |
| Structural role of protein | Keratin --> hair, finger nails, toe nails, outer dead layer of skin Myosin --> major protein involved in the contraction of skeletal and cardiac muscle Collagen --> Major protein in connective tissue (elasticity of skin) |
| Metabolic role of protein | Many proteins function as enzymes (biological catalysts) Many proteins act as horomones, they are chemical messengers in the blood that help to regulate many metabolic activities. |
| Vitamins | Organic compounds needed in small quantities in the diet ot ensure a good standard of health. They are complex, carbon-based substances that the body cannot make. |
| Vitamins | Organic compounds needed in small quantities in the diet ot ensure a good standard of health. They are complex, carbon-based substances that the body cannot make. |
| Water soluble vitamin | Vitamin C |
| Fat soluble vitamin | Vitamin D |
| Vitamin C | Ascorbic acid |
| Vitamin D | Calciferol |
| Sources of vitamin C | fruit and veg (especially citrus fruits such as oranges and lemons) |
| What does vitamin C do? | Assists in the absorption of iron from the gut and also to maintain strong connective tissue |
| Disease caused by lack of vitamin C + symptoms | Scurvy Lose teeth, poor healing, bleeding gums, easy bruising, internal bleeding |
| Sources of Vitamin D | milk, eggs, liver, fish liver oils, produced by the skin when exposed to U.V. light |
| What does Vitamin D do? | Absorption of calcium and phosphorous from the gut, healthy bone formation and maintenance |
| Disease caused by deficiency of Vitamin D + symptoms | rickets (children) osteomalacia (adults) late teething and walking, deformed legs and arms, and weak bones |
| Minerals | Soluble inorganic salts that contain elements essential for a healthy metabolism. They are neeed in minute quantities by the body to maintain a healthy body. |
| Plants absorb their minerals from | Soil water |
| Animals obtain minerals through | their diet |
| Plant mineral requirements | Magnesium --> chlorophyll Calcium --> middle lamella |
| Animal mineral requirements | Calcium --> teeth and bones Iron --> haemoglobin |
| Importance of water | Cell's cytoplasm and body's fluids Universal solvent Metabolic processes e.g. photosynthesis & respiration Enables dissolved substances to move through cell membranes Shape of the cell Good absorber of heat energy Chemical reactions : condensation reactions, hydrolysis reactions, photosynthesis, respiration |
Want to create your own Flashcards for free with GoConqr? Learn more.