Food and Digestion 1

Balanced diet

a diet consisting of right type of foods in the correct amount

Five food groups

carbohydrates, fats/lipids, proteins, minerals, vitamins

Carbohydrates are made from

carbon, hydrogen, oxygen

Carbohydrates function

supply cells with energy

How does glucose supply the body with energy

Glucose is broken down by respiration into carbon dioxide and water and energy is stored as ATP

Monosaccharides

Galactose, fructose, glucose

Galactose

6C, found in milk, soluble

Fructose

6C, found in fruits, soluble

Glucose

6C, found in starchy foods, soluble

Hexoses

monosaccharides that have 6 carbon atoms in each molecule

deoxyribose

5C, found in DNA nucleic acids, soluble

Ribose

5C, found in RNA nucleic acids, soluble

Pentoses

monosaccharides that have 5 carbon atoms in each molecule

Disaccharides

Maltose, Lactose, Sucrose

Maltose

glucose + glucose, found in digestion of starch, insoluble

Lactose

glucose + galactose, found in milk, insoluble

Sucrose

glucose + fructose, found in fruits, insoluble

Polysaccharides

Starch, cellulose, glycogen

Starch

glucose, carbohydrates stored in plants, insoluble

Cellulose

glucose, cells walls, insoluble

Glycogen

glucose, glycogen, carbohydrates stored in animals and fungi, insoluble

Fibre functions

absorbs water, helps muscle in the gut push food, bacteria feed of fibre to produce vitamins

Why couldn’t we digest fibre

we lack its enzyme cellulase

Lipids are made from

Carbon, hydrogen, oxygen

what is the structure of lipids

3 fatty acids and one glycerol

Saturated fats

solid, increase levels of bad cholesterol, found in animal fat, have no bonds

Unsaturated fats

liquid, increase levels of good cholesterol, found in vegetable oil, have double bonds

how make liquid fats into solid

break the double bonds using hydrogen

Lipids function

storage of energy, acts as a heat insulator, protection of organs

Proteins are made from

carbon, hydrogen, oxygen, nitrogen

proteins function

needed for growth and repair of the body

Structural proteins

insoluble, used for structure, ex. collagens, elastins

Functional proteins

soluble, carry out activities, ex. enzymes, haemoglobin

Primary proteins

form polypeptide chains

Secondary proteins

use H-bonds, characteristic structures that occur in many proteins

Tertiary proteins

use H-bonds and ionic bonds, three dimensional structures

Quaternary structures

use more than 2 chains, three dimensional structures of proteins composed of multiple subunits