Cell Molecules Part 2 - Organic Molecules
Cell Molecules Part 2 - Organic molecules:
Chemical which contains carbon and hydrogen bond are called organic molecules. They are Carbohydrates, lipids, proteins, nucleic acids etc. They are present in protoplasm and combines with O, P, N and S over and above C and H.
Carbohydrates:
Formula – Cn (H2O) m
Types of carbohydrates:
- Monosaccharide:
- Formula – (CH2O)n, value of n lies between 3 to 8
- Simple carbohydrates
- Contains carbonyl group (C=O)
- Sweat in taste and soluble in water
- Helps in energy transformation process
- Enters in cell very easily.
- Example – Glucose, Galactose, Ribose, Deoxyribos
- Disaccharides:
- Formula – Cn(H2O)n-1
- Two monosaccharide joins by glycosidic bond and forms disaccharides.
- Sweat in taste and soluble in water
- Cannot enter in cell directly.
- Example – sucrose, maltose, lactose
- Polysaccharides
- Formula – (C6H10O5)n
- Large number of monosaccharide joins by glycosidic bond and forms a long chain called as polysaccharides.
- Example – starch, glycogen, cellulose
Biological importance of carbohydrates:
- Useful in energy transformation process
- Helps in metabolism of cells and constitution of tissues
- Helps in respiration process.
Lipids:
They are oily and viscous molecules. They are insoluble in water and soluble in organic solvents like benzene, chloroform and ether.
Types of lipids:
· They are made up of alcohol and fatty acids.
· Example – triglycerides – one molecule of alcohol (glycerol) and three molecules of fatty acids
· Each fatty acids contains carbon witch binds with hydroxyl group of alcohol by ester bond and releases water molecules
· Fatty acids are of two types – long chain fatty acids (more than 8 carbon atom) and short chain fatty acids (2 to 8 carbon atom)
· Fatty acids can be either saturated or unsaturated.
· Saturated fatty acids contains single between all carbon atom and cannot accept new hydrogen atoms.
· Unsaturated fatty acids contain double bond between nearby carbon at one or more places and accepts new hydrogen atom.
· Saturated fatty acids are present in solid fats and unsaturated fatty acids are present in liquid oils.
· They are made up of alcohol, fatty acids and additional non-lipid constituent.
· They are named on based of their non-lipid constituent.
· Example – Glycolipids – carbohydrate
Phospholipids – phosphate
Lipoprotein – protein
They are made up of only alcoholic part and called as sterols.
They do not contain fatty acids
Example – cholesterol, testosterol, progesterone
Biological importance of lipids:
- It releases energy which is double than the carbohydrates
- It stores food in form of fat and oils
- It acts as a solvent for fat soluble vitamins like A, D, E, and K.
- It helps in formation of enzymes and hormones
- Phospho-lipids are used in formation of plasma-membrane and membranes of organelles.
- Steroids are the important constituents in plasma-membrane and present in some hormones.
- Lipids form an insulating layer around nerve fibers or under the skin and provide protection.
Self study:
Example-1: Which of the following is the example of carbohydrates?
a) Glucose
b) Sucrose
c) Glycogen
d) All of above
Answer: All of above examples are different types of carbohydrates.
Example-2: Polysaccharide contains …………between large umber of monosaccharide molecules.
a) Glycosidic bond
b) Ester bond
c) Hydrogen bond
d) Alcoholic bond
Answer: Polysaccharide contains glycosidic bond between large umber of monosaccharide molecules.
Example-3: Lipids are soluble in ………………
a) Physiological solvents
b) Inorganic solvents
c) Organic solvents
d) Water
Answer: Lipids are soluble in organic solvents.