3. Which of the ff. is a producer? \( \begin{array}{ll}\text { a. fish } \quad \text { b. shrimp } \quad \text { c. algae } \quad \text { d. crab }\end{array} \) \( \begin{array}{l}\text { 4.All the organisms below are decomposers except } \\ \text { a. fungi } \quad \text { c. bacteria } \\ \text { b. sea lion } \quad \text { d. fungi and bacteria } \\ \text { 5. Arrange the feeding relationship of the ff. organisms living in } \\ \text { intertidal zone }\end{array} \) Fish ------seaweeds------shore birds

What one of the following are the CORRECT operating conditions when autoclaving biohazard wastes? (A) \( 10 \mathrm{psi} 121^{\circ} \mathrm{C} \) for 15 minutes. (B) \( 10 \mathrm{psi}, 121^{\circ} \mathrm{C} \) for 30 minutes. (C) \( 15 \mathrm{psi}, 121^{\circ} \mathrm{C} \) for 15 minutes. (D) \( 15 \mathrm{psi}, 121^{\circ} \mathrm{C} \) for 30 minutes. After conducting microbiology experiment, a laboratory technician is required to dispose the remaining culture broths. Which one of the following is the CORRECT disposal method? (A) Incineration. (B) Discard as normal waste. (C) Collection by licensed waste collectors. (D) Autoclave before discarding into the drain.

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.

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) \( 128 \mathrm{cmu} / \mathrm{cm}^{2} \)

(C) State TWO ways in which fermentation process helps to improve [2 marks] quality of food products.

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? \( \begin{array}{ll}\text { (A) } \quad \text { Diatoms. } \\ \text { (B) } \quad \text { Sarcodines. } \\ \text { (C) } \quad \text { Sporozoans. } \\ \text { (D) }\end{array} \)