Biological Molecules

Question 1

Carbohydrates

Answer 1

Long chains of simple sugars
Glucose is a simple sugar ( a monosaccharide)
When 2 glucose molecules join together maltose is formed (a disaccharide)
When lots of glucose molecules join together starch, glycogen or cellulose can form (a polysaccharide)

Question 2

Fats

Answer 2

Most fats (lipids) in the body are made up of triglycerides
Their basic unit is 1 glycerol molecule chemically bonded to 3 fatty acid chains
The fatty acids vary in size and structure
Lipids are divided into fats (solids at room temperature) and oils (liquids at room temperature

Question 3

Proteins

Answer 3

Long chains of amino acids
There are about 20 different amino acids
They all contain the same basic structure but the ‘R’ group is different for each one
When amino acids are joined together a protein is formed
The amino acids can be arranged in any order, resulting in hundreds of thousands of different proteins
Even a small difference in the order of the amino acids results in a different prot

Question 4

Structure of a DNA Molecule

Answer 4

DNA, or deoxyribonucleic acid, is the molecule that contains the instructions for the growth and development of all organisms
It consists of two strands of DNA wound around each other in what is called a double helix
The individual units of DNA are called nucleotides
All nucleotides contain the same phosphate and deoxyribose sugar, but differ from each other in the base attached
There are four different bases, Adenine (A), Cytosine (C), Thymine (T) and Guanine (G)
The bases on each strand pair up with each other, holding the two strands of DNA in the double helix
The bases always pair up in the same way:
Adenine always pairs with Thymine (A-T)
Cytosine always pairs with Guanine (C-G)