Biochemistry

Question 1

What are the ‘building blocks’ for protein macromolecules?

Answer 1

Amino acids

Question 2

What are the ‘building blocks’ for polysaccharides?

Answer 2

Carbon, hydrogen and oxygen

Question 3

What are the ‘building blocks’ for nucleic acids?

Answer 3

Nucleotides / Codons

Question 4

What are the ‘building blocks’ for lipid aggregates?

Answer 4

Triglycerides and 3 fatty acids

- Carboxyl group and hydrocarbon chain

Question 5

What macromolecule/s can be made up of branched chains?

Answer 5

polysaccharides / carbohydrates

Question 6

How many standard amino acids are there?

Answer 6

20

Question 7

What is the general structure of an amino acid? (diagram is ok)

Answer 7

Alpha carbon
Carboxyl group
Amino Group
“R” Group

Question 8

How do standard amino acids differ from one another?

Answer 8

The side chain or R group differs between amino acids

Question 9

Amino acids can be classified using their R group. Why might it be useful to use this classification?

Answer 9

Amino acids with similar properties will allow us to understand why the protein fold is a certain way and whether a particular amino acid can be replaced with another without drastically changing the proteins structure.

Question 10

What is a peptide bond?

Answer 10

A peptide bond is a chemical bond formed between two molecules when the carboxyl group of one molecule reacts with the amino group of the other molecule, releasing a molecule of water (H2O).

Question 11

Explain why amino acids are so important

Answer 11

Source of energy
Precursors to other biomolecules
They are the building blocs of the body

Question 12

What is a Protein primary structure?

Answer 12

Primary structure is the linear order of amino acids in a protein

Question 13

What is a protein secondary structure?

Answer 13

Secondary structure is the regular geometric structure the amino acids fold into based on their favourable interaction which is determined by their properties.

Question 14

What is a protein tertiary structure?

Answer 14

Tertiary structure is the native form which the secondary structures fold into based on the properties of the amino acid chains.

Question 15

What is a protein quaternary structure?

Answer 15

Quaternary structure is when two or more polypeptide structures form together to create a protein.

Question 16

List two examples of terms that describe different secondary structures that can be found in proteins.

Answer 16

Helix

Sheets

Question 17

List four of the major roles of protein

Answer 17

Transport
Storage
Motion (of limbs)
Structural support

Question 18

Lipids should not be considered a true macromolecule because of their structure. Briefly explain.

Answer 18

They are not held together by covalent bonds

Question 19

Name three major functions of lipids

Answer 19

Fuel
Insulation
Protection

Question 20

List some examples of lipid aggregates

Answer 20

Micelles
Liposomes
Membranes
Lipoproteins

Question 21

Give one example of an important monosaccharide

Answer 21

D- Glucose
D- Fructose
D- Ribose

Question 22

Give one example if important Disaccharides

Answer 22

Sucrose
Lactose
Maltose

Question 23

List four major functions of carbohydrates in a cell.

Answer 23

Energy source
cell to cell communication
Cell recognition
Cell adhesion

Question 24

Can two sugar molecules have different configurations despite having the same molecular formula. Briefly explain

Answer 24

Yes, depending on the environment they are in and the surrounding chemicals, the molecules will configure themselves appropriately.

Yes, Glucose mutarotation will change the configuration as well as stereoisomers.

Question 25

Explain the term Diabetes melitus

Answer 25

The bodies state of hyperglycaemia. Your bodies insulin production is inhibited and glucose is removed through the urine.

Question 26

Discuss the statement “The diagnosis and management of Diabetes mellitus is only of concern to a very small portion of the healthcare industry”. (Hint, you should first decide if this statement is true or false, then BRIEFLY explain why it is true or false.)

Answer 26

Diabetes is a growing non-communicable disease around the world and should be taken seriously as such. Type 1 diabetes is particularly uncommon, however, type 2 is more prevalent due to its correlation with diet and exercise. Currently the disease may only affect a small portion of the industry, however, it has the possibility to grow and therefore should be of concern to more than a small portion.

Question 27

How is Diabetes mellitus diagnosed?

Answer 27

Glycosuria (urine test) is suggestive.

Blood glucose test is diagnostic.

Question 28

Spectrophotometers can be used to measure the absorbance of light of a particular wavelength by a certain material. BRIEFLY explain what is meant by the term absorbance.

Answer 28

The light is either absorbed, scattered or reflected by a material which lowers the amount that is transmitted through the material itself. This is absorbance.

Question 29

What is Beer’s Law?

Answer 29

Beers law states that there is a directly proportional relationship between absorbance and concentration.

Concentration increases –> Absorbance increase

Question 30

What is Lambert’s Law?

Answer 30

As pathlength increases, absorbance increases

Question 31

What is the combined Lambert-Beer Law?

Answer 31

Absorbance is related to both pathlength and concentration.

Question 32

Is it more convenient to use Absorbance or Transmittance to determine the concentration of a substance?

Answer 32

The absorbance is more convenient

Question 33

Why is the selection of optimal analytical wavelength important for spectrophotometry measurement? (Hint, material to be discussed in the Biochemistry Practical may assist you to answer this.)

Answer 33

In order to find the correct concentration you have use the optimal wavelength that the solution or material will absorb. If you know the light will be absorbed you can measure the remaining light that isnt absorbed to determine the transmission or absorbance of the material.

Question 34

Why is the selection and use of an appropriate Blank important for spectrophotometry measurement? (Hint, material to be discussed in the Biochemistry Practical may assist you to answer this.)

Answer 34

You are calibrating the machine to know what the base line is for no colour, like taring the scales before you use them.