For the following DNA sequences, create a complementary section: \[ C-G-A \] \[ -L-T-C \]

(B) State TWO ways in which flagellum helps a microorganism survive in an open environment. (2 ma All rights reserved. No part of this publication may be reproduced, stored in a retrieval sys transmitted in any form or by any means, electronic, mechanical, photocopying, reco otherwise, without the prior written permission of the Institute of Technical Education, Singapo Institute of Technical Education has made every effort to trace copyright holders, but if inadvertently overlooked any, we will be pleased to make the necessary arrangements a

23 Which one of the following microorganisms moves using flagellum? (A) Amoeba. (B) Euglena. (C) Paramecium. (D) Plasmodium. Which one of the following is NOT a heterotrophic microorganism? \( \begin{array}{ll}\text { (A) } \quad \text { Diatoms. } \\ \text { (B) } \quad \text { Sarcodines. } \\ \text { (C) } \quad \text { Sporozoans. } \\ \text { (D) }\end{array} \)

21 When conducting the bioluminescence assay, a false positive result is detected if the sample (A) contains a lot of fat. (B) comprises of artificial dye. (C) has high initial microbial load. (D) is contaminated with chemicals. The function of cell wall in bacteria is to (A) store nutrients. (B) protect them against drying. (C) control the reproduction rate. (D) maintain the characteristic shape.

(A) State ONE example of selective media that can be used to isolate [3 marks] EACH of the following microorganisms. (i) Gram positive bacteria. (ii) Staphylococci spp. (iii) Gram negative bacteria.

34 (A) (i) Explain ONE purpose of air monitoring. (ii) Describe TWO factors that will affect air quality.