EIS Teaching – Learning Strategies / Procedures

Biology Secondary 4, duration 60 min.

Teacher: Mr.Wichai Likitponrak

Look at this Picture!

What is

This?

Carbohydrates

Carbohydrates Contain the Elements:

Carbon

Hydrogen

Oxygen

They Are Split Into Three Groups Known As:

Monosaccharides(Monomers)

Disaccharides(Dimers)

Polsaccharides(Polymers)

Carbohydrates

•Many carbohydrates are soluble in water.

•The usual chemical test for the simpler

carbohydrates is heating with Benedicts solution.

•The formula for a carbohydrate is (CH2O)n

•The n represents the number of times the CH2O

unite is repeated.

Benedicts Test

Monosaccharides(monos) The Most Important Monosaccharide Is

Glucose.

A Monosaccharide is made up of 1 sugar unit.

Monos are reducing sugars.

Fructose and Galactose are all so

Monosaccharides, They all have the same chemical

formula but different structures.

Three Monosaccharides

C6H12O6 Hexose ; n=6

Disaccharide : Glycosidic Bond

This is when two monosaccharides join to form a Disaccharide.

The reaction is similar to condensation.

The reaction involves the water been given off.

There are three types of Disaccharides:

1. Sucrose

2. Lactose

3. Maltose

Glycosidic Bond

Above is the

structures of a

Glycosidic bond.

It forms a

Disaccharide

Dehydration Synthesis

of a Disaccharide

Formation of Disaccharides

Hydrolysis

This is the breaking down of a glycosidic bond.

Instead of water been taken away water is added.

Lysis means splitting.

Hydrolysis of a Disaccharide

Important Polysaccharides: Starch

Consists of glucose subunits Plant energy storage molecule Glycogen is a very similar molecule in animals. Starch and glycogen can be digested by animals.

Starch test

Important Polysaccharides: Cellulose Composed of glucose subunits

Different bond formed than starch

Structural component in plants

Cannot be digested by animals

Review by this VDO!!!

http://www.youtube.com/watch?v=_zm_DyD6FJ0

Your Group Activity.

Your Group Result.

SAMPLE TEST RESULT

Starch Non Starch

Ex. Potato

A

B

C

D

E

Assignment:

Worksheet

1.1

1.2

1.3

Sent me back

in this class !!!

THANK YOU FOR YOU

ATTENTION !!!