S2 Biology Madras College

It is important to maintain a healthy balance of : Carbohydrates. Proteins Fats Vitamins and Minerals Fibre Water

Carbohydrates are found in these foods above We need carbohydrates for energy

Proteins are found in foods such as : Red meat Fish Eggs Cheese We need proteins for growth and repair

Fats are high in any fried or fast food We need some fats for: Proper function of the heart Maintenance of the blood system Brain development and function Excess fat is stored under our skin or around our organs

Vitamins and Minerals are substances which the body needs in very small quantities to work properly. Vitamin/MineralFunction Vitamin AEye function Vitamin B groupEnergy from food (respiration) Vitamin CMaintain healthy skin and gums IronProduction of Red Blood Cells CalciumHealthy bones and teeth (with Vit. D) IodineMaintain normal cell function

Junk Food contains many ingredients which are generally bad for you. These are generally known as…

Junk food is alright to have once in a while, but should not be eaten regularly.

Crown Root Enamel Dentine Gum Pulp Cavity Cement Bone

An adult has 32 teeth in total. Incisors Canines Pre-molars Molars Wisdom teeth

Bacteria on teeth use sugar from our food. The Bacteria multiply to form plaque. The Bacteria make acid. The acid slowly burns through the enamel to create a cavity. The bacteria continue to make acid using food stuck in the cavity. Eventually, the cavity extends to the pulp cavity and causes toothache!

It is important to brush your teeth regularly! Use a good toothbrush. You may wish to use mouthwash too.

Regular brushing is important for all members of the family!

Mouth Gullet Liver Stomach Gall Bladder Pancreas Large Intestine Small Intestine Appendix Rectum Anus

Teeth begin mechanical breakdown of food. Saliva contains Amylase (Carbohydrase) enzyme to begin digestion of Carbohydrates.

Passes food from the Mouth to the Stomach. Food is moved along the gut by a process called PERISTALSIS. Fibre in the diet helps the gut move food along easily. Muscles in gullet wall contract behind bolus Bolus squeezed along gut. Bolus of food Gullet

The Stomach churns our food. It makes Protease enzyme for Protein digestion. It makes Hydrochloric Acid to kill germs.

The Liver makes Bile. Bile is stored in the Gall Bladder. Bile breaks down fat into small droplets. This is EMULSIFICATION. Liver Gall Bladder

Fat Bile Lipase enzyme can now digest fat easier

The Pancreas makes enzymes for the digestion of Carbohydrates, Proteins and Fats. It also helps control blood/sugar levels. Liver Stomach Gall Bladder & Bile Duct Small Intestine Pancreas

Digestion is completed in the Small intestine. Small and soluble food particles pass into the blood by absorption. The Small intestine has a very large surface area due to Villi. Villus Small Intestine Blood capillary

Large food molecules broken down by enzymes Small soluble food molecules pass into the blood.

Mostly undigested food and Fibre passes into the Large Intestine. Water and Minerals are absorbed into the blood here.

This is the breakdown of large insoluble molecules into small soluble molecules. Digestion allows food to be absorbed by the blood. Large Insoluble Food Molecule Small Soluble Food Molecules

If the name ends in –ase, its an enzyme

Starch is broken down into Sugar (Glucose). Amylase is a Carbohydrase enzyme. Starch Amylase Simple Glucose can now be absorbed into the bloodstream Amylase breaks bonds between Sugar molecules

Proteins are broken down into Amino Acids. Pepsin from the Stomach is a Protease enzyme. Pepsin Pepsin breaks down the long proteins into shorter proteins Other Protease enzymes break down short protein chains into Amino Acids. Amino Acids are absorbed into the blood

Lipase digests Fat. Fat is broken down into Glycerol and Fatty Acids. Fatty Acids Glycerol Lipase enzyme Fatty Acids and Glycerol absorbed separately into bloodstream A Fat Molecule

This is the process which your cells use to make energy.

Larynx (voice box) Trachea (windpipe) Bronchi Bronchioles Diaphragm muscle Rib Rib muscleAlveoli or air sacs are found at the ends of the Bronchioles

Deoxygenated blood from heart Oxygenated blood back to heart Film of moisture Capillary

Diaphragm contracts and moves downwards. Rib muscles contract and ribcage moves upwards and outwards. Volume in chest increases. Pressure in chest decreases. Air is Inhaled. Diaphragm relaxes and moves upwards. Rib muscles relax and ribcage moves downwards and inwards. Volume in chest decreases. Pressure in chest increases. Air is Exhaled.

Inhaled air is 78% Nitrogen, 20% Oxygen, 1% Carbon Dioxide and 1% Rare gases. Exhaled air contains less Oxygen (16%) and more Carbon Dioxide (5%). Nitrogen (78%) Nitrogen (78%) Oxygen (20%) Oxygen (16%) Carbon Dioxide Rare Gases

Normal AirExhaled Air In Exhaled air, the candle goes out sooner because there is less Oxygen in it. 0 seconds2 seconds4 seconds6 seconds8 seconds10 seconds

Exhaled Air Carbon Dioxide gas turns Limewater cloudy Limewater

Water turns blue Cobalt chloride paper pink Cobalt Chloride paper

The cilia beat and move mucus containing dirt and germs up to the back of the throat Cilia

Mucus Trapped dirt and germs are moved towards the mouth