F3 - SEM1 - CARBOHYDRATES

Question 1

What elements is Carbohydrates composed of?

Answer 1

Composed of element C, H, O
General formula is Cx(H2O)y
H:O ratio is 2:1

Question 2

What are the functions of Carbohydrates?

Answer 2

Provide immediate energy
Storage of energy

Question 3

What are the sources of Carbohydrates?

Answer 3

Glucose
- grape, fruit

Starch
- rice, noodle

Question 4

What are the 3 groups of Carbohydrates

Answer 4

Monosaccharides (simple sugar)
Disaccharides
Polysaccharides

Question 5

What are the properties of Monosacharides (simple sugar)?

Answer 5

Soluble in water
Sweet
Can crystalline
All have reducing power (for food test) - form brick red precipitate in Benedict test

Question 6

What are the Source of Monosacharides?

Answer 6

Grape
Fruit
Milk

Question 7

What are common example of Monosacharides?

Answer 7

Glucose
Fructose
Galactose

Question 8

What are the functions of simple sugar?

Answer 8

Provide immediate energy - glucose (most important), fructose
Carbohydrates are transported in our blood in this form

Question 9

List example of Disaccharides and provide their source and composed of?

Answer 9

Maltose - glucose + glucose, from germinating barley
Sucrose - glucose + fructose, from cane
Lactose - glucose + galactose, from milk

Question 10

How to combine Monosacharides to become Disaccharides?

Answer 10

Condensation ( -H2O )

Question 11

How to break down Disaccharides to Monosaccharide

Answer 11

Hydrolysis ( +H2O )

Question 12

What are the properties of Disaccharides?

Answer 12

Soluble in water
Sweet
Can Crystalline
Have reducing power except Sucrose

Question 13

What is the function of Disaccharides?

Answer 13

Carbohydrates are transported in plant in this form

Question 14

What is Polysaccharides?

Answer 14

Compose of > 300 simple sugar molecules to form long chain by condensation

Question 15

What are properties of Polysaccharides?

Answer 15

Insoluble in water
Not sweet

Question 16

What are examples of Polysaccharides?

Answer 16

Starch
Glycogen
Cellulose
Lignin

All made of glucose but in different linkage

Question 17

What are the functions and sources of below Polysaccharides?

Starch
Glycogen
Cellulose
Lignin

Answer 17

Starch - food reserve in plants, sources are storage organ, rice, noodle, bread, potatoes
Glycogen - food reserve in animal, sources are liver, skeletal muscle
Cellulose - structural materials in plants, (component of cell wall), sources are cell walls of plant cells
Lignin - structural materials in plants (component of thick cell wall), sources are cell walls of plant cells

Question 18

What happens if lacks of Carbohydrates?

Answer 18

Lack of energy to do activities

Question 19

How to test below Carbohydrates and what are the positive result?

Reducing sugar
Glucose
Starch

Answer 19

Reducing sugar - Benedict’s test, blue to brick red precipitate
Glucose - Glucose test paper, depends
Starch - Iodine test, brown to dark blue

Question 20

What happens if excessive uptake of Carbohydrates?

Answer 20

Store as glycogen in liver and skeletal muscle
If much more, change into Lipin and store in adipose tissue, e.g. under skin (subcutaneous fat), around the organ