Which one of the following statements about the aging male is TRUE? It takes less time for an older male to achieve an erection. Orgasmic contractions are more intense in the older male. Less direct physical stimulation is need for sexual arousal. Testosterone production decreases as men age.

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:

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

Can a star-nosed mole be tamed as a house pet?