Biological Molecules

Question 1

What roles do small molecules do?

Answer 1

• They are the building blocks of macromolecules (a molecules containing a very large number of atoms such as a protein, nucleic acid, or a synthetic molecule).
• They may also have a other specific function in their own right.

Question 2

What are the types of monosaccharides?

Answer 2

• Ketone based (ketose)

- Aldehyde based (aldose)

Question 3

What is the composition of a cell?

Answer 3

• water=70%
• inorganic ions= 1%
• small organic molecules=3%
• macromolecules=26%

Question 4

What are the features of a monosaccharide?

Answer 4

• all have the formula of (CH2O)n
• they have a chiral center
• are enantiomeres
• examples include glucose and hexose

Question 5

How is a disaccharide created?

Answer 5

Through a condensation reaction between two monosaccharides, creating a glycosidic bond between the two molecules as well as removing a water molecule.
Examples include:
-sucrose (a-glucose + fructose)
-lactose (a-glucose + galactose)
-maltose (a-glucose + a-glucose)

Question 6

How is a polysaccharide created?

Answer 6

Through a condensation reaction between three or more monosaccharides/disaccharides, creating a glycosidic bond between the molecules as well as removing water molecules.
Examples include:
-starch
-glycogen
-cellulose

Question 7

What is an oligosaccharide?

Answer 7

It is a form of polysaccharide which contains a small number of monosaccharides.
They can form a different variety of antigens that are found on blood cells (this is what differentiates blood groups).

Question 8

What are the different levels to protein structure?

Answer 8

• Primary structure- covalent bond forming a polymer i.e. the sequence of amino acids
• Secondary structure- regular folded form that is stabilised by hydrogen bonds e.g. helices sheets
• Tertiary structure- overall 3D structure that is stabilised by HID, hydrophobic/hydrophilic and Van der Waals interactions.
• Quaternary structures- organisation of macromolecules into assemblies, often stabled by ionic bonding.

Question 9

How are peptides created?

Answer 9

Peptides can be created through a condensation reaction between amino acids to form peptide bonds as well as removing water.

Question 10

What are nucleotides?

Answer 10

Nucleotides are essential components to our body functions for example ATP, secondary messenger and RNA synthesis.

Question 11

What is cholesterol?

Answer 11

-a steroid
-it’s is able to intercalate into the membrane
*the OH group is able to interact with polar lipid heads
*its steroid scaffold can interact with fatty acids
*decreases fluidity and increase flexibility of
membrane
-reduces permeability for soluble molecules

Question 12

What are body fats?

Answer 12

• body fats act as food reserves and are broken down for energy
• there are three different types
• saturated
• cis-unsaturated
• trans-unsaturated

Question 13

Name a few diseases that can occur in single molecules.

Answer 13

• diabetes- the absence of a protein hormone leads to the failure of regulating blood glucose
• sickel cell disease- one amino acid change in a globi change causes hemoglobin to aggravate into polymers
• cystic fibrosis- absence of CTFR membrane protein leads to altered properties of secretion

Question 14

What is a triglyceride made up of?

Answer 14

Made up of a glycerol molecule and three fatty acid tails via condensation.