Health and Lifestyle Knowledge Organiser

Definition of Digestion: Digestion is defined as the breaking down of large insoluble food molecules into small soluble ones.
Purpose of Digestion: These small molecules are absorbed into the blood for your body to use.
Role of the Mouth: The mouth is the initial stage where food is chewed. Salivary glands are located here and add enzymes to the food.
Oesophagus (Gullet): This tube carries food from the mouth to the stomach.
Stomach Functions: The stomach performs two types of digestion:
- Physical digestion: The stomach churns the food.
- Chemical digestion: It begins the chemical digestion of proteins.
The Role of the Liver and Gall Bladder:
- The liver makes bile.
- The gall bladder stores bile.
- The bile duct is the pathway through which bile travels to the small intestine.
The Pancreas: This organ is responsible for making enzymes used in the digestive process.
The Small Intestine: This is the site where digested food is absorbed into the blood.
The Large Intestine: Water and minerals are absorbed into the blood here.
Microbial Activity: Bacteria live on the fibre in your diet within the large intestine and make important vitamins, such as vitamin K.
Waste Management:
- Rectum: Stores faeces.
- Anus: Expels faeces.

Nutrients and Their Roles:
- Carbohydrates: Serve as the main source of energy for the body.
- Lipids: These include fats and oils which provide energy.
- Proteins: Essential for the growth and repair of tissues.
- Vitamins and Minerals: Required in small amounts to maintain health.
- Water: A critical component needed in all cells and body fluids.
- Fibre: Although not technically a nutrient, it provides bulk to food to keep it moving through the gut.

Starch Test:
- Procedure: Add a few drops of lodine solution to the food solution.
- Positive Result: The solution turns blue-black if starch is present.
Lipids Test:
- Procedure: Add a few drops of ethanol to the food solution, shake it, and leave for $1$ minute. Then pour the ethanol into a test tube of water.
- Positive Result: If the solution turns cloudy, the food contains lipids.
Sugar Test:
- Procedure: Add a few drops of Benedict's solution to the food solution and heat it in a water bath.
- Positive Result: If the solution turns orange-red, the food contains sugar.
Protein Test:
- Procedure: Add a few drops of copper sulfate solution and sodium hydroxide solution to the food solution.
- Positive Result: If the solution turns purple, the food contains protein.

Balanced Diet: Defined as having the right proportions of the food groups to keep you healthy.
Consequences of an Unbalanced Diet:
- Underweight Individuals: Face an increased risk of a poor immune system, lack of energy, and vitamin and mineral deficiencies.
- Overweight Individuals: Face an increased risk of heart disease, stroke, diabetes, and some cancers.
Specific Vitamin Deficiencies:
- Vitamin A deficiency: Can lead to night blindness.
- Vitamin D deficiency: Can lead to rickets.

Definition: Enzymes are special proteins that can break large molecules of nutrients down into small molecules.
Function: They are known as biological catalysts because they speed up digestion without being used up.
Digestive Enzyme Types:
- Carbohydrase: Speeds up the digestion of carbohydrates (e.g., starch) into sugars.
- Protease: Speeds up the digestion of protein into amino acids.
- Lipase: Speeds up the digestion of lipids into fatty acids and glycerol.

General Definition: Drugs are any chemicals that affect the way your brain and body work.
Medicinal Drugs:
- Used in medicine and benefit health if used correctly.
- Used to treat symptoms or cure illness.
- Some have side effects.
- Examples: Painkillers, antibiotics, and cough mixture.
Recreational Drugs:
- Taken for enjoyment, to relax, or to stay awake.
- Normally provide no health benefits.
- Many can be harmful or illegal.
- Examples: Alcohol, caffeine, heroine, cocaine, and tobacco.

Alcohol:
- Classified as a depressant because it slows down body reactions.
- Long-term effects of heavy drinking: Stomach ulcers, heart disease, reduced fertility, brain damage, and liver damage (cirrhosis).
- Risks during pregnancy: Miscarriage, stillbirth, premature birth, low birth weight babies, and Foetal Alcohol Syndrome (FAS).
Smoking:
- Tar: Clogs the lining of the lungs and alveoli; contains cancer-causing chemicals.
- Nicotine: An addictive stimulant.
- Carbon Monoxide: Stops blood from carrying oxygen.
- Associated diseases: Heart disease, emphysema, strokes, lung cancer, and respiratory infections.
- Risks during pregnancy: Increased risk of miscarriage, low birth weight babies, and negative effects on foetal development.

Addiction: Occurs when your body becomes used to the chemical changes caused by a drug and you need to take the drug to feel normal.
Withdrawal Symptoms: Experienced when an addicted person tries to stop taking a drug. Symptoms include:
- Sickness and nausea.
- Stomach cramps.
- Headaches.
- Anxiety and sweating.

Digestive system terms: digestion, balanced diet, carbohydrates, lipids, protein, vitamins, minerals, fibre, water, nutrient, small intestine, large intestine, stomach, oesophagus, rectum, anus, pancreas, liver, gall bladder, bile duct.
Chemical and biological terms: enzyme, biological catalyst, carbohydrase, protease, lipase, starch, sugar, iodine solution, Benedict's solution, copper sulfate, sodium hydroxide, ethanol.
Lifestyle and health terms: drug, medicinal drug, recreational drug, addiction, withdrawal symptom, stimulant, depressant, tar, nicotine, carbon monoxide, cirrhosis, rickets, night blindness, Foetal Alcohol Syndrome (FAS), starvation, obese, deficiency.