Biological Molecules Flashcards
1
Q
State the four major types of polysaccharides.
A
Starch, glycogen, chitin, cellulose
2
Q
Two structural polysaccharides.
A
Chitin & cellulose
3
Q
Name two energy-storing polysaccharides
A
Starch and glycogen
4
Q
Name the energy-storing polysaccharide in animals
A
glycogen
5
Q
Name the polysaccharide found in the cell walls of some fungi.
A
chitin
6
Q
Name the polysaccharide found in the cell wall of plant cells.
A
Cellulose
7
Q
What is a monosaccharide? Give an example.
A
Simple sugar (e.g. glucose, fructose)
8
Q
State two functions of lipids in organisms.
A
- Structural component of cell membranes (phospholipid bi-layer).
- Energy source (fats & oils)
9
Q
What are the four levels of protein structure? Briefly explain each.
A
- Primary – the sequence of amino acids that make up the primary structure is determined by the sequence of bases on mRNA, which in turn is determined by the sequence of bases on DNA.
- Secondary – the coiling or folding of sections of the polypeptide due to hydrogen bonding is determined by the primary structure or sequence of amino acids.
- Tertiary – the 3D shape of a single polypeptide, is determined by both its primary and secondary structures and is due to interactions such as di-sulphide bridges, ionic bonds and hydrogen bonds.
- Quaternary – the 3D shape of two or more polypeptides, due to interactions and chemical bonding between the polypeptides.
10
Q
State three differences between DNA and RNA.
A
- DNA contains the base thymine, whereas RNA contains the base uracil.
- DNA contains the sugar deoxyribose, whereas RNA contains the sugar ribose.
- DNA is double stranded, whereas RNA is generally single stranded.
11
Q
State the base-pairing rules in DNA.
A
- Adenine with thymine
- Guanine with cytosine
