Must mention high concentration. Ignore reference to other factors if reasoning is appropriate. 2 (b) (i) O || C N – | H; 1 (ii) 10; 1 (c) Action of vanilomycin depends on fluidity of membrane; Fluidity reduced / not fluid at low temperatures; Pore formed by gramicidin A remains in place / permanent; 3 (d) Pore between sterol molecules lined with polyene antibiotic; Hydrophobic region next to sterol; 2 [9] M3. (a) (i) Molecule/protein/glycoprotein; Stimulates immune response; (That causes) production of antibodies; 2 max (ii) Antigens on HIV are different (shape); So, antibody will not complementary (to antigen); ‘fit’/not Receptor sites on antibody specific to one antigen; 2 max (iii) (Has site with) same shape as salmonella antigen so binds to anti-gal antibodies; (Has site with) same shape as receptor molecule so that HIV will bind; Binds to both molecules; 2 max
Must mention high concentration. Ignore reference to other factors if reasoning is appropriate. 2 (b) (i) O || C – N | H; 1 (ii) 10; 1 (c) Action of vanilomycin depends on fluidity of membrane; Fluidity reduced / not fluid at low temperatures; Pore formed by gramicidin A remains in place / permanent; 3 (d) Pore between sterol molecules lined with polyene antibiotic; Hydrophobic region next to sterol; 2 [9] M3. (a) (i) Molecule/protein/glycoprotein; Stimulates immune response; (That causes) production of antibodies; 2 max (ii) Antigens on HIV are different (shape); So, antibody will not ‘fit’/not complementary (to antigen); Receptor sites on antibody specific to one antigen; 2 max (iii) (Has site with) same shape as salmonella antigen so binds to anti-gal antibodies; (Has site with) same shape as receptor molecule so that HIV will bind; Binds to both molecules; 2 max
Year1Comprehension.docx