Thursday, January 18, 2001

Midterm Exam #1

Microbiology 509

Name: KEY KEY KEY KEY KEY KEY KEY KEY KEY KEY KEY KEY KEY KEY KEY KEY

Œ   Place your name at the top of each page.

   There are 27 questions

Ž   Each question worth the same amount

   Remember: distinguish compared items by linking descriptions to terms (e.g., the sky isblue).

   Unless requested, do not multiply out expressions (e.g., stop at 2*5003 rather than 2.5x108).

   I encourage you to ask questions during the exam, but do so discretely.

   Remember to use safe, i.e., unambiguous & well-articulated answers whenever possible.

   Above all, avoid jumping to profoundly incorrect conclusions: make sure you actually read a question (all of it) before you answer, and then make sure you are actually answering what it is you are being asked.

 

(1) A bright-field compound microscope cannot see most viruses. Why not?

A: viruses are too small; bright-field compound microscopes cannot adequately magnify most viruses while retaining sufficient resolution (chapter 3)

 

(2) A water solution with an excess of hydroxyl ions is said to be __________.

A: basic (chapter 2)

 

(3) Another name for endoflagella is __________.

A: axial filament (chapter 4)

 

(4) Which taxonimic category (i.e., level)-which is above the level of kingdom-contains just three taxa: Archaea, Bacteria, and Eukarya.

A: domain (chapter 4)

 

(5) Before viewing through a microscope, how does one normally kill the organisms in a smear?

A: by heat fixing the smear (chapter 3)

 

(6) By what criteria is the Gram stain not a simple stain?

A: different organisms are stained different colors (differentially) (chapter 3)

 

(7) Disaccharides are sugars that consist of two _________ linked together. (though a category of sugars, sugar or sugars is not the answer, nor are specific kinds of sugars)

A: monosaccharides (chapter 2)

 

(8) Fermentation pathways (as opposed to, for example, glycolysis) are employed by microorganisms to produce what substance?

A: NAD+ (chapter 5)

 

(9) For which of the following are individual organisms typically largest in size?

(i)                  Bacteria

(ii)                Helminths

(iii)               Protozoa

(iv)              Unicellular algae

(v)                Viruses

(vi)              Yeasts

A: (ii) Helminths (these are multicellular animals, the rests are individual eukaryotic cells, or not even prokarytic or not even cells) (chapter 1)

 

(10) How does one minimize refraction when employing highest magnification in light microscopy?

A: by employing immersion oil between the specific (object) and objective lens (chapter 3)

 

(11) In aerobic respiration, glucose (for example) is broken down entirely into __________ and __________ with some of the energy released from glucose's bonds employed to phosphorylate ADP to produce ATP. (answers are two kinds of molecules)

A: Water and carbon dioxide (chapter 5)

 

(12) Matching: (a) Lister, (b) Semmelweis, (c) Koch, (d) Fleming, (e) Pasteur, (f) Hooke.

(i)                  Antibiotics

(ii)                "Cell"

(iii)               Chemical antimicrobials

(iv)              Puerperal sepsis

(v)                Rabies

(vi)              Tuberculosis

A: (i) (d) Fleming, (ii) (f) Hooke, (iii) (a) Lister, (iv) (b) Semelweis, (v) (e) Pasteur, (vi) (c) Koch (chapter 1)

 

(13) Molecules that consist at one end of a single, unbranched hydrocarbon chain and at the other end consist of a hydrophilic carboxylic acid group are called __________. (looking for a name specific to molecules possessing these structural characteristics)

A: fatty acids, soap (chapter 2)

 

(14) Name 3 things that can adversely affect enzyme activity.

A: Too-high temperatures; too-low temperatures; too-high salt concentrations; too-low salt concentrations; too-high pH; too-low pH; various poisons/toxins/inhibiting substances; etc. (chapter 5)

 

(15) Name a function of bacteria pili.

A: attachment/adherence to other things including tissue that the bacterium is infecting or other bacteria (sex pilus) (chapter 4)

 

(16) Organisms possessing which types of nutritional patterns are most people most familiar with? (choose two)

(i)                  Chemoautotroph

(ii)                Chemoheterotroph

(iii)               Photoautotroph

(iv)              Photoheterotroph

A: (ii) Chemoautotroph; (iv) Photoheterotroph (chapter 5)

 

(17) Peptide bonds are found in __________.

(i)                  Carbohydrates

(ii)                Lipids

(iii)               Nucleic acids

(iv)              Proteins

A: (iv) Proteins (chapter 2)

 

(18) Pure water is always __________ to cells suspended in it.

(a)    Harmless

(b)   Hypertonic

(c)    Hypotonic

(d)   Isotonic

A: Hypotonic (chapter 4)

 

(19) RNA and DNA are examples of

(i)                  Carbohydrates

(ii)                Hydrocarbons

(iii)               Lipids

(iv)              Nucleic acids

(v)                Proteins

(vi)              Steroids

A: (iv) Nucleic acids (chapter 2)

 

(20) The conversion of a vegetative cell into an endospore is called _________ and the conversion of an endospore into a vegetative cell is called __________.

A: sporulation, germination (chapter 4)

 

(21) The production of acid and __________ is used diagnostically as an indication of the occurrence of mixed-acid fermentation by such organisms as Escherichia coli.

A: Gas (chapter 5)

 

(22) The smallest distance between two dots that a microscope is capable of distinguishing is called the _________ of that microscope.

A: resolution (chapter 3)

 

(23) What is NAD+'s primary job in metabolism, e.g., such as it displays in the course of glycolysis.

A: NAD+'s primary job in metabolism is the removal of hydrogen atoms/removal of electrons from substances (chapter 5)

 

(24) Which is the least likely to be found in an aquatic environment

(i)                  Algae

(ii)                Bacteria

(iii)               Fungi

(iv)              Protozoa

(v)                Viruses

A: (iii) Fungi (because they tend to be adapted to terrestrial environments (chapter 1)

 

(25) Which of the following are not mostly possessed by both Gram-negative and Gram-positive bacteria:

(a)    Cell wall

(b)   Murein

(c)    Nucleoid

(d)   Plasma membrane

(e)    Teichoic acid

A: (e) Teichoic acid (which is found only in Gram positives) (chapter 4)

 

(26) Which scientist contributed the least to the development of the germ theory of disease (that is, the development of the idea rather than "simply" its implementation or application)?

(i)                  Fleming

(ii)                Koch

(iii)               Lister

(iv)              Pasteur

(v)                Van Leeuwenhoek

A: (i) Fleming, who contributed to the implementation of the germ theory of disease rather than its development (chapter 1)

 

(27) Why do medical microbiologists care about arthropods?

A: because arthropods serve as vectors of infectious disease (e.g., bacterial or protozoa) (chapter 1)