26 April 2015

F4, chapter 4: pt 2;Chemical composition of the cell

CARBOHYDRATES

Contains Carbon, Hydrogen, and Oxygen
The ratio of hydrogen atom and oxygen atom is 2:1






F4, chapter 4: pt 1;Chemical composition of the cell

CHEMICAL COMPOUND OF THE CELL:

A) ORGANIC
-Carbohydrates
-Proteins
-Lipids
-Nucleic Acid

B) INORGANIC
-Water


THE IMPORTANCE OF ORGANIC COMPOUNDS

I) proteins
 -made up elements C, H, O, N, P
-build new cells
- required in th synthesis of enzymes( tertiary), antibodies.

II) carbohydrates
- elements C, H, O
-starch is main energy store of carbohydrate in plant
- glycogen is main energy in human and animal tissues
- cellulose forms the cell walls of plant cell

III) lipids
- C, H, O
-eg: fats, oils, waxes, phospholipids, steroids.
-fats slouble vitamins: Vitamins A, D,E ,K
-waxes prevent water loss in plants

IV) Nucleic acids

structure of nucleotide:


 







Two types of nucleic acid:
A) deoxyribonucleic acid (DNA)
 - found in nucleus, chloroplast, mitochondrion
-contains genetic information

B) ribonucleic acid (RNA)
-found in cytoplasm, ribosomes, and nucleus
-copies information carried by DNA