Which statement best describes the difference between normal and pathological anxiety? Normal anxiety becomes pathological when a person acknowledges the anxiety. Pathological anxiety is always triggered by external events, whereas normal anxiety is not. Normal anxiety is an appropriate response to real threats, while pathological anxiety may not have an identifiable cause and can be disproportionate to the situation. Normal anxiety lasts for a longer duration compared to pathological anxiety.

(A) (i) Describe TWO disadvantages of using Replicate Organism Detection And Counting (RODAC) plate during a surface swab. (ii) Explain TWO purposes of conducting a hand swab test. 12 m

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.

(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

(B) (i) Explain THREE precaution steps during decontamination of biohazard wastes in bag using an autoclave. (ii) Describe TWO materials that will remain undamaged after autoclaving.

Calculate the cfu/cm \( \mathrm{cm}^{2} \) for a tested surface of 4 cm in length and 3 cm in width if the number of colonies on the agar plate is 96 cfu. (A) \( 8 \mathrm{cfu} / \mathrm{cm}^{2} \) (B) \( 12 \mathrm{cmu} / \mathrm{cm}^{2} \). (C) \( 72 \mathrm{cmu} / \mathrm{cm}^{2} \) (D) \( 128 \mathrm{cmu} / \mathrm{cm}^{2} \)