Yr 10 - Medical Science: Food Groups

Food is an example of chemical potential energy; energy stored in the bonds

between atoms. Different foods are made of different elements and therefortherefore

contain different nutrients. We need several types of nutrients for our bodies

to work properly.

There are 6 major classes of

nutrients (3 we need to remember)

• Carbohydrates

• Proteins

• Lipids

• Fibre

• Vitamins

• Mineral

Carbohydrates

Most carbs come from plants

Complex carbs

• Made of larger molecules

• Takes longer to break down

• Good energy source for endurance athletes

• e.g. starch (potatoes, pasta, bananas, grains)

Simple carbs

• Made of smaller molecules

• Provides instant energy as they are easily absorbed

• e.g. glucose (lollies and sports drinks), sucrose (table sugar), fructose (fruit)

Proteins make up the main structural part of animal cells, so foods high in protein are usually animal products

Proteins are essential for all organisms - they are used for:

Simple carbs

• Made of smaller molecules

• Provides instant energy as they are easily absorbed

• e.g. glucose (lollies and sports drinks), sucrose (table sugar), fructose (fruit)

Carbohydrates -(Amylase)→ Maltose→Glucose

Proteins

Proteins make up the main structural part of animal cells, so foods high in protein are usually animal products

Proteins are essential for all organisms - they are used for:

• Growth

• Repairing tissue

• Making hormones and enzymes

• Used as a backup energy source

Protein -(Pepsin)→Amino acids

Lipids

Lipids is the collective name for oils (liquid) and fats (solid). Most fats come from

animal sources and most oils come from plant sources.

Lipids are required for:

• energy

• making cell membranes

• insulation and keeping us warm

• protecting our internal organs

Lipids -(Lipase)→ Triglycerides → Glycerol + Fatty Acids