Using Key Terms 1. Identify the bacterial STD that causes ulcers or chancres. \( \begin{array}{ll}\text { 2. Classify each of the the following STDs as bacterial } \\ \text { or viral. } \\ \begin{array}{ll}\text { a. gonorrhea } & \text { c. chlamydia } \\ \text { b. HPV } & \text { d. syphilis } \\ \text { 3. Identify the possible symptom caused by HPV. } \\ \begin{array}{ll}\text { a. fever } & \text { c. jaundice } \\ \text { b. genital warts } & \text { d. blisters }\end{array} \\ \text { Understanding Key Ideas } \\ \text { 4. List three ways in which sexually transmitted } \\ \text { diseases can be spread. }\end{array}\end{array} \).

23 Which of the following statements is TRUE about the methylene blue reduction test (MBRT) conducted for pasteurised milk samples? \( \begin{array}{ll}\text { (A) } \quad \text { Microbial load of milk samples can be determined quantitatively. } \\ \text { (B) } \quad \text { Decolourization of methylene blue is caused by the loss of electrons. } \\ \text { (C) A UV-Vis spectrophotometer is required to monitor the colour change. } \\ \text { (D) } \quad \text { Milk sample with longer reduction time is of better quality than sample with } \\ \text { shorter reduction time. }\end{array} \) CC)

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

An unknown microbial specimen measures 18 millimetres under a total magnification of 400 x , when examined under the microscope. What is the actual size of the unknown specimen? \( \begin{array}{ll}\text { (A) } 45 \text { micrometres. Total magnification }=400 x \\ \text { (B) } 4.5 \text { micrometres. } \quad \frac{18}{400 x}=0.045 \mathrm{~mm} \\ \text { (C) } 0.45 \text { micrometres. } \\ \text { (D) } 0.045 \text { micrometres. } & \text { micrometers }=0.045 \times 1000=45 \text { micrometers }\end{array} \)

Suppose there are 30 bacteria in a Petri dish at start time. Seven hours later, there are 360 bacteria in the dish. 1.) Express the number of bacteria, P, as a function of \( t \) hours passed. Note: Round the growth rate to 4 dec. places. \( P(t)= \) 2.) Use the model from part a to determine the number of bacteria, rounded to a whole number, in the dish after 20 hours:

Which of the following anterior teeth have a cingulum that is located off-center toward the distal? a) Maxillary lateral incisorb) Maxillary caninec) Mandibular central incisord) Maxillary central incisor