WEEK 10: Proteins and enzymes - tumour markers

Question 1

cover up to slide 5

Question 2

what are proteins?

Answer 2

amino acid polymers

Question 3

describe the structure of proteins

Answer 3

the amino group from one amino acid combines with the carboxyl group of another amino acid to form a peptide bond

Question 4

describe the differences between primary, secondary, tertiary and quaternary structures.

Question 5

describe the differences between primary, secondary, tertiary and quaternary structures.

Question 6

what does it mean if a protein has amphoteric proterties?

Answer 6

can act as both acid and a base

Question 7

what happens in the biuret method?

Answer 7

peptide bonds react with copper in alkaline solution to give coloured chelate.
The colour is dependent on the number of peptide bonds.

Question 8

what happens in the Folin-Lowry method?
give a pro and con.

Answer 8

protein estimation where phosphomolybdic acid is reduced by tryptophan.
Sensitive but expensive.

Question 9

recap kjeldahl, direct absorbance, refractometer and methods on 16

Question 10

what methods are used for albumin estimation?

Answer 10

react with anionic dyes:
BCG - bromocresol green
BCP - bromocresol purple

Question 11

what happens when CSF total protein increases?

Answer 11

Increased permeability of blood-brain barrier

Brain tumour or inflammation due to bacterial or viral meningitis

Question 12

what is troponin?

Answer 12

protein marker - cardiac markers

Question 13

where are proteins synthesized?

Answer 13

in the liver - all except hormones and immunoglobins

Question 14

how do proteins pass into plasma

Answer 14

by active transport and passive diffusion