Biology Forum Microbiology microb problems

last updated by kabuto 18 years ago
3 voices
4 replies
  • Author
    Posts
    • #4469
      kabuto
      Participant

      1. Which of the following has no cell wall?

      a. Chlamydia
      b. Myxoplasma
      c. Clostridium
      d. Nosardia

      My answer: d

      2. Actinomycetes are different from fungi because it

      a. chemoheterotroph
      b. doesn’t have membrane-bounded nucleus
      c. need light
      d. causes disease

      My answer: d

      3. You are given 3 flasks (A<B and C) which are inoculated with E coli. A contain glucose, B contain glucose and lactose while C contains lactose. After 24 hours, which flask would contain beta_galactosidase?

      a. A
      b. B
      c. C
      d. A and B
      e. B and C

      My answer: e because lactose can be degraded to galactosidase.

      4. Viroid contain

      a. only RNA
      b. only DNA
      c. only protein
      d. RNA and DNA

      My answer: d
      I read that viroid consist only of nucleic acid, not sure if it means DNA, RNA or both of them,

      5. All the following are heavy metal used as antimicrobial agent except

      a. iodine
      b. merthiolate
      c. selenium sulphate
      d. copper sulphate

      My answer: c.
      I know b and d is correct. A is used as anti microbial agent but not sure if it is considered as heavy metal

    • #46330
      sdekivit
      Participant

      in the last question: iodine is not a metal –> it’s a halogen and is used as a desinfectant.

    • #46380
      kabuto
      Participant
      quote sdekivit:

      in the last question: iodine is not a metal –> it’s a halogen and is used as a desinfectant.

      ok, thanx. how about the rest of the questions?

    • #46388
      shmolex
      Participant

      For #3, I’m not entirely sure about this, but I think it should be C. I think it depends on how fast the E. Coli uses up the glucose. E. Coli should use up the glucose before using lactose as an energy source. If the glucose is used up before 24 hours, then E.coli should move on to lactose, allowing for the production of B-galactosidase. If not, then it shouldn’t have B-galactosidase.

      My guess is that the question should be testing for the understanding that glucose is used as an energy source before anything else, so I would think the answer is C.

      As for the other questions, those are pretty much fact based and I’m too lazy to bother looking them up.

    • #46399
      kabuto
      Participant

      💡 uhm, thanks a lot!!

You must be logged in to reply to this topic.

Members