Microbio exam 2

What site on an enzyme is where the substrate binds?

·       Active site

What organic molecule binds to enzyme?

·       Coenzymes

What is a catabolic pathway?

·       Chemical reactions that break down complex molecules into simple molecules releasing ATP

Is nitrogen fixed to ammonia by cyanobacteria?

·       Yes cyanobacteria can turn nitrogen into ammonia

What are light reactions of photosynthesis?

·       Energy from sunlight is transferred into NADPH and ATP

Can E. coli ferment lactose?

·       Yes

Can micro bacterium degrade cholesterol?

·       Yea certain species are capable

Is oxygen necessary for the electron transport chain?

·       Yes oxygen is necessary

In batch culture how does the log phase of the bacterial growth curve appear?

·       Linear on a plotted semi-log scale

Know how to describe enzyme of extreme alkaphiles?

·       pH is extremely high ranging from pH 8-pH 10.5

Know the correct order of the correct phases of the growth phase?

·       lag phase, log (exponential) phase, stationary phase, and death (decline) phase. 

Know how to describe the cell membrane of microbes that thrive at low temperatures

·       Has a high portion of unsaturated fatty acids

Differential and Selective Media: know the difference

·       Differential media contains specific ingredients or chemicals to distinguish species growing on a plate. Selective media inhibits growth. Of certain microbes so only specific microbes can grow

Know that fungi vs bacteria which one survives in a dry environment

·       Fungi is better equipped to survive in dry environments

Halo Bacteria: know if it grows in a low or high salt concentration

·       High salt concentration

Halo tolerant microbes (know which one cause food poisoning?

·       Staphylococcus aureus

·       Bacillus cereus

·       Listeria monocytogenes

Who identified nucleotide bases in DNA and RNA?

·       Albrecht kossel

Where did Mendel publish his work?

Who worked on chromosomal inheritance?

·       Walter Sutton and Theodor Boveri

One gene or one enzyme theory hypothesis: Who worked on that?

·       George Beadle and Edward Tatum

Evidence that DNA was a genetic material rather than a protein? Which scientists

·       Alfred Hershey andMartha Chase

Who first demonstrated horizontal transmission of information?

·       Fredrick. Griffith

There is a relationship between adenine and guanine and the other two who rule is it?

·       Chargaff’s Rules

·       Adenine and guanine

·       Cytosine and thymine

Who suggested that dna molecule has 3 strands?

·       James Watson and Francis Crick

What is located at the end of a 5 end dna strands?

·       A phosphate group

Stop codons are also known as what?

·       Termination codons

·       Nonsense codons

What amino acid are also attactached to tRNA?

·       Uracil?

·       Aminoacyl-tRNA synthetase enzyme

Where is uracil found?

·       RNA

What is another name for a template strand?

·       Antisense strand

What occurs during transcription? Polymerase binds to what

·       RNA polymerase on the promoter region

Ducarotic undergo slicing?

Prokaryotes have a single origin of replication or not?

·       Prokaryotes only have one origin of replication in their dna

Eukaryotes may have multiple or not?

·       Multiple origins or replication on each chromosome

What are the milk borne pathogens?

·       Bacteria, protozoa and viruses

·       Listeria, e.coli, salmonella (bacteria)

·       Cowpox, Hep A (viruses)

Does commercial sterilization kill microbes?

·       Yes; sterilization kills microbes

Can pasteurized foods spoil?

·       Yes; milk

What do autoclaves use to sterilize materials?

·       Pressurized steam

Does sonication causes capitation in cells?

·       Yes, cavitation will result from sonication

What do hepafilters filter?

·       Airborne particles, mostly microbes to control microbial growth

Know X-rays and gamma rays? Are ionizing radiation and do they cause thymine dimmers?

·       X rays are emitted from the electron cloud surrounding an atom. Gamma rays originate from inside the nucleus

·       Thy are ionizing radiation but do not directly cause thymine dimmers

·       Thymine dimmers are caused by UV rays

Are soaps with no added ingredients bacterialicidal?

·       No they are not bactericidal

Know what method of biomedical control does not rely on a d nature in protein

·       Lyophilization

Phenolic compounds are found naturally in what organisms?

·       Vascular plants

What is a fomite?

·       Inanimate object that can be contaminated with infectious microorganisms and serve as vehicle for transmitting disease to a new host

·       Example, a toy a snot nose kid sneezed on then I pick it up

Hepafilters are required for which biosafety level?

·       Biosafety level 2 and up

Aseptic technique carries out what?

·       Prevents spread of infection by avoiding contamination.

·       Example: Field must be kept sterile, sterile gloves and work space

Why are extracellular polymeric substances important?

·       Act as a protective matrix providing adhesion to surfaces, structural stability, nutrient exchange,  and protection from pH changes, desiccation, and antimicrobial agents.

What media is commonly used to determine oxygen requirement of a bacterial species?

·       Thioglycolate broth

How would a microaerophile grow in a thyoglycolic tube?

·       Just below the surface of the tube

What microbes live in a salt lake?

·       Halophiles

What microbes can survive the ocean?

·       Thermophiles

·       Barophiles

Where in the DNA structure do dna binding proteins bind?

·       The major groove

What is a phenotype?

·       An observable trait told by sight of the person

Know log phase and lag phase

·       Lag phase Is the first few seconds to minutes where there is no growth of bacterial cells

·       Log phase is rapid growth of bacterial cells

·       Stationary phase is when the number in death and growth are equal; constant/ plateau

·       Death or decline is when the death rate has now taken over the process

Thermophile and mesophile

·       Thermophiles live in deep sea ocean vents. Can with stand temps from 50 degrees Celsius to 80 degrees Celsius

·       Mesophile are in the middle surviving temps from 20 degrees Celsius to 45 degrees Celsius. Most human pathogens are mesophiles

The different anaerobes know them

·       Obligate anaerobes need oxygen in order to survive and prosper

·       Obligate anaerobes will die in the presence of oxygen

·       Facultative anaerobes can succeed with oxygen however rely on fermentation and anaerobic respiration

·       Aerotolerant anaerobes do not require oxygen but will also not die in the presence of oxygen

·       Microaerophiles require a very little amount of oxygen to survive