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Human Nutrients - Coggle Diagram
Human Nutrients
Nutrition
Carbohydrates
Uses:
Supply energy
Sources:
Rice
Bread
Pasta
Potatoes
Maize
Sugar
Honey
Fats and Oils
Uses:
Source of energy
Energy store
Building materials
Insulation (keeps body warm)
Buoyancy
Making hormones
Sources:
Butter
Oil
Nuts
Seeds
Avocados
Fatty fish
Meat
Proteins
Uses:
Energy (if needed)
Building materials (growth & repair)
Enzymes
Haemoglobin
Structural material (muscle)
Hormones
Antibodies
Sources:
Meat
Fish
Eggs
Beans
Peas
Lentils
Milk
Cheese
Soy products
Nuts
Vitamin C
Uses:
Collagen formation
Resistance to diseases
Sources:
Citrus fruits
Tomatoes
Vitamin D
Uses:
Helps absorption of calcium
Sources:
Fish liver oil
Dairy
Egg yolk
Sunlight
Calcium
Uses:
Development of strong bones
Maintenance of teeth
Sources:
Milk
Cheese
Leafy vegetables
Iron
Uses:
Making haemoglobin
Sources:
Red meat
Liver
Spinach
Legumes
Fibre (Roughage)
Uses:
Provides bulk for faeces
Helps peristalsis
Sources:
Vegetables
Fruits
Whole grains
Bran
Water
Uses:
Chemical reactions
Solvent for transport
Sources:
Drinks
Fruits
Vegetables
Metabolic reactions
Deficiencies
Vitamin C: Scurvy; loss of teeth, pale skin & sunken eyes
Calcium/Vitamin D: Rickets, Osteoporosis; weak bones and teeth
Digestive System
Process of Digestion
Ingestion: taking substances (e.g. food, drink) into the body through the mouth.
Physical/Mechanical Digestion: breakdown of food into smaller pieces without chemical change.
It increases the surface area of food for the action of enzymes in chemical digestion.
Chemical Digestion: breakdown of large, insoluble food molecules into small, soluble molecules.
Absorption: the movement of nutrients from the intestines into the blood
Assimilation: uptake and use of nutrients by cells
Egestion: the removal of undigested food from the body as faeces
Main Organs in the Alimentary Canal
Mouth: contains teeth used for mechanical Digestion, an area where food is mixed with salivary amylase & where ingestion takes place
Salivary glands: produce saliva, which contains amylase and helps food slide down the oesophagus
Oesophagus: tube-shaped organ that uses peristalsis (circular muscle contract and relax) to transport food from mouth to stomach
Stomach: has pepsin (a protease that works best in acidic conditions) to break down proteins into amino acids and kills bacteria with hydrochloric acid. They also have elastic walls.
Mechanical digestion in the stomach occurs via peristaltic contractions of the smooth muscle.
Small intestine: tube-shaped organ composed of three parts:
Duodenum: fats are emulsified by bile and digested by pancreatic lipase to form fatty acids and glycerol. Pancreatic amylase and trypsin (a protease) break down starch.
Jejunum (not in syllabus)
Ileum: Maltase breaks down maltose to glucose. This is where absorption also takes place.
Pancreas: produces amylase, trypsin (a protease that works best in alkaline conditions), and lipase.
Liver: produces bile (emulsifies fats, neutralises acidic fat molecules), deamination, and makes urea to be sent to the kidney. Also, it is the site of the breakdown of alcohol and other toxins.
Gall bladder: stores bile from the liver
Large intestine: tube-shaped organ composed of two parts:
Colon: organ for absorption of minerals and vitamins and reabsorbing water from waste to maintain the body’s water levels
Rectum: where faeces are temporarily stored
Anus: a ring of muscle that controls when faeces is released.
Teeth
Teeth
Help in mechanical digestion
Increase surface area of food
Incisors
Rectangular shape
Sharp
Function: Cutting and biting
Canines
Sharp-pointed
Function: Piercing and tearing
Premolars
Blunt
One or two roots
Cusps/bumps at the end
Function: Chewing and grinding
Molars
Blunt
Two or three roots
Ridges at the end
Function: Chewing and grinding
Structure
Enamel: the strongest tissue in the body made from calcium salts
Cement: helps to anchor tooth
Pulp: contains tooth-producing cells, blood vessels, and nerve endings that detect pain.
Dentine: calcium salts deposited on a framework of collagen fibers
Nerves: Detect sensation
Blood vessels: Provide nutrition
The Stomach
The stomach lining contains many smooth muscles that contract to squeeze physically and mix the food with the strong digestive juices present, a process also known as "stomach-churning."
The food will be digested within the stomach for several hours
First stop for protein digestion
chemical digestion
Chemical Digestion: the breakdown of large insoluble molecules into small soluble molecules
The role of chemical digestion is to produce small soluble molecules that can be absorbed
Enzymes in Digestion
Maltase: breaks down maltose into glucose in the membrane of the epithelium lining in small intestines.
Lipase: breaks down lipids into fatty acids and glycerol, produced by the pancreas.
Amylase: breaks down starch into maltose; it is produced in the pancreas (secreted into the duodenum) and salivary glands.
Protease: breaks down proteins into peptides and amino acids. Pepsin comes from the stomach (acidic), and trypsin comes from the pancreas (alkali).
Hydrochloric Acid and Bile
Functions of Hydrochloric acid in gastric juice:
Denaturing enzymes in harmful microorganisms
Giving the optimum pH for pepsin activity
Kills pathogens
Bile:
Produced by the liver
Stored in the gall bladder, transported by the bile duct
an alkaline mixture that neutralises the acid mixture of food and gastric juices entering the duodenum from the stomach to provide a suitable pH for enzyme action.
Bile helps with the digestion of fats by breaking them down from large molecules to smaller molecules, making a larger surface area.
Absorption and Villus
Absorption: the movement of nutrients from the intestines into the blood
The small intestine is the region for absorption of digested food through diffusion, osmosis, and active transport.
The small intestine is folded into many villi, increasing the surface area for absorption. One villus will have tiny folds on the cells on its outside called microvilli.
The epithelium is one cell thick, allowing efficient diffusion of nutrients.
A large surface area means more absorption of nutrients can happen.
Lacteals: absorbs fatty acid and glycerol
Capillaries: provide a good blood supply and a steep concentration gradient.
Goblet Cells: Produces mucus
Most water is absorbed from the small intestine, and some from the colon (large intestine).
Diet
Balanced Diet: A diet that includes the appropriate amounts of carbohydrates, proteins, fats and oil, vitamin (C and D), mineral ions (calcium and iron), fibre and water needed to support the body's growth, energy needs, and overall health:
Diet-related to age/gender/lifestyle:
Children Below 12: Require more calcium
Teenagers: Highest calorie intake
Adults: Balanced meal with fewer calories
Pregnant Women: more iron, calcium
Males: Generally require more energy