| BIO Notes On Organic Chemistry Essay, Research Paper
The chemistry of life
(Living things made mostly of carbohydrates, fat and protein)
CARBOHYDRATES energy producer
· Contain carbon, hydrogen and oxygen
· Glucose is the simplest (dissolves easily in water) monosaccharide
· Starch is also common (solid, lots of glucose molecules in a chain (condensation)) disaccharide
· Starch is broken down into glucose as well (add wateràhydrolysis)
FAT energy producer insulation and energy store
· Contain carbon, hydrogen and oxygen
· Contains more carbon + hydrogen
· Fat molecule is made up of glycerol and fatty acids.
· Condensation and hydrolysis play parts here?
PROTEIN
· Contain carbon, hydrogen, oxygen, nitrogen (and sulphur)
· Made of blocks (amino acids) and links (peptide links)
· 22 amino acids in nature
· Hydrolysis à chain of proteins split (polypeptides) then broken to small amino acids
· Reverse in condensation
· Soluble proteins make up enzymes.
· Denaturalisation occurs when molecule shape changes when heated.
CHEMICAL REACTIONS
· Occur mainly in gut and cells
· Reactions in cells is metabolism
· Breaking down or joining options
· All reactions are catalysed by enzymes.
Enzymes
IMPORTANCE
· To speed up reactions
· They are biological catalysts
· TYPES
Extracellular enzymes are produced and leave cell to work outside
· Intracellular enzymes work inside cell
ENZYME CONTROLLED REACTION
· Maltose (substrate) àmaltase (enzyme) à glucose (product)
PROPERTIES
· Always proteins
· Specific
· Reusable
· Destroyed by heat over 45 Celsius
· Sensitive to pH
HOW DO THEY WORK?
· Enzyme molecule has active site
· Substrate fits into active site
· Reaction takes place
· Products leave site.
HELPING HINDERING
· Anything which helps substrate reach enzyme speeds up reaction
· Poisons stop temporarily/ permanently the active site
ENZYME USE
· Biological washing powders
· Tenderising meats, skinning fish, removing hairs
· Softening vegetables, removing seed coats
· Syrups, fruit-juices, chocolates
Food and Diet
OUR DIET
· Carbohydrates
· Fats
· Proteins
· Water
· Minerals
· Vitamins
CARBOHYDRATES
· Sugar gives energy
· Starch are normally found in small grains called starch granules they also give us energy
· Cellulose for plants make a cell wall for humans it makes a dietary fibre keeping the food moving along the gut
FATS
· Mainly give us energy
· Saturated means that there is no more room for atoms to add on to the existing molecule.
· Unsaturated is the opposite.
PROTEINS
· Needed for growth repair and slight amounts of energy
· Kwashiorkor à disease with the lack of protein
· Proteins are made of amino acids
· Essential amino acids are ones we cannot make but instead take in digestively
WATER
· Absolutely essential
· Needed in all life forms and contained in mostly all substances
MINERALS
· Sodium. Is a salt. It helps messages to be sent and muscle contraction. Lack of causes cramps in muscles
· Calcium used for hardening our bones and teeth. Hardening can only take place when they take up calcium phosphate and carbonate (calcification). Lack of causes rickets (soft, weak, deformed bones).
· Phosphorus. We need it to be absorbed into the calcium. It occurs in membranes.
· Iron. Present in haemoglobin (transports O2). Lack of cause anaemia: less O2 transported, less energy.
· Iodine. Trace element: needed in tiniest quantities. We get from sea food and drinking water. Needed to make thyroxine. Lack of causes goitre or ?Derbyshire neck?: swelling of thyroid gland next to Adam?s apple.
· Fluorine. Trace element. Prevents tooth decay.
VITAMINS
· Collection of organic substances which control reactions in the body.
· (A). Retinol: important for our eyes. Lack of causes night-blindness or xerophthalmia. Fat soluble
· (B). Niacin (nicotinic acid). Lack of: Pellagra. Thiamine: lack of is Beri-beri. Riboflavin: causes sores in skin around mouth. Water soluble
· (C). Ascorbic acid. Keep epithelia healthy. Lack of cause scurvy: bleeding in various parts of the body. Water soluble
· (D). Calciferol. Helps child?s bones become strong. Lack of cause rickets. Can be obtained from fish liver oil or the body through sunlight. Fat soluble
· (E). Found in milk and egg yolk. Lack of cause sterility. Fat soluble
· (K). Helps blood clot. Lack of causes internal, external bleeding. Fat-soluble.
· Composition of different foods helps us identify useful substances.
· Vegetarian: eats no animal meat but does eat products. Vegans do not eat animal products.
· Food additives: substances that are added to food. Some give change to colour, taste, preservation or consistency.
How substances are stored
WHY DO ORGANISMS STORE SUBSTANCES?
· So that they can survive when food is unavailable or scarce
· Man can survive several weeks
WHERE ARE SUBSTANCES STORED?
· The main storage place is the liver for humans.
· For plants they swell up and make the swelling the storage place. The plant storage organ can survive harsh conditions then a new plant spouts and the food is moved there.
PLANTS STORAGE SYSTEM
· Green plants produce glucose that is either used straight away or turned into starch and converted back to glucose when needed.
· Other substances can be made from glucose in plants (oil, sugar)
REQUIREMENTS FOR TURNING STARCH INTO GLUCOSE
· Enzyme
· Can be tested with starch
HOW STARCH IS TURNED INTO GLUCOSE
· Glucose molecules join together and coil up forming a starch grain (condensation)
· The starch grain can de-coil and split up forming Glucose (hydrolysis)
ANIMALS STORAGE SYSTEM
· Get glucose from food
· They turn glucose into glycogen
· Glycogen is a bondage of glucose molecules linked together
· Stored in the liver
· It is also stored as fat
MOBILISATION
· This is when a solid form of food has to be transported and it is broken down into a solution.
· Starch and glycogen are broken down into glucose.
· Fat is broken down into fatty acids and glycerol
IMPORTANCE OF FOOD STORES
· Storage of food in organisms usually mean they are going to be packed together closely, this means anything like this can be a rich source for humans
Obtaining energy from food
FOOD CONTAINING ENERGY
· We can check this by burning food and estimating the amount of heat given out. (kJ)
· kJ per Gram carbohydrates-17, fat-39, protein-18
ENERGY CONTAINED IN FOOD
· determines how it should be cooked
· Depends on substances inside the food.
ENERGY PER DAY
· Basal metabolic rate: rate at which body processes take place
· Roughly 7000kj per day if lying down doing nothing
· At least 9200 kJ per day for doing nothing but essential tasks
EXCESS EATING
· Most excess not used is turned into fat. Body weight increases
· Obesity is when we take in more energy (through food) than we give out.
· More exercise, consumption of less energy-containing foods stop or decrease obesity
MINIMAL EATING (STARVATION)
· First energy stores from fat will be used up.
· Takes energy from muscles
· Becomes thin and weak
· Anorexia nervosa: psychological loss of appetite
· Marasmus wasting away due to starvation
Energy release-respiration
FOOD BURNING
· Oxygen is needed
· Carbon dioxide, water and heat are produced
ENERGY PRODUCTION IN HUMANS
· C6H12O6 + 6O2à 6CO2 + 6H2O + ENERGY
· We can check the relationship between O2+CO2 and breaking down of food by using radioactive tracers and mice.
ENERGY USES
· Animal-movement, messages, transportation, warmth, growth, cell division, osmosis, and life!
· Plants taking up mineral salts, opening/closing stomata, transporting food substances, growth, cell division, osmosis, and life!
CHEMISTRY OF RESPIRATION
· Respirometer measures amount of oxygen taken in
· Energy produced from glucose is linked to adenosine triphosphate (ATP)
· Breakdown of glucose is used to make ATP
· ATP not Glucose gives energy towards muscle contractions
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