HW 1-3 Flashcards
During the 4-billion-year history of life on earth, all organisms were microbial during the first:
1)500 million years
2)1 billion years
3)2 billion years
4)3 billion years
5)3.75 billion years
3 billion years
A Winogradsky column provides a favorable growing environment for which of the following types of microorganisms?
1)Photosynthetic aerobes
2)Nitrogen fixing chemolithotrophs
3)Anaerobic microbes that require limited or no light
4)Chemolithoautotrophs
5)All of the above
All of the above
Koch
Development of pure culture techniques
Pasteur
Disproving Spontaneous Generation
Lister
Promoted disinfection of medical environments
van Leeuwenhoek
Producing a microscope to allow observation of bacteria
The organisms that produces most of the oxygen in the atmosphere of the early earth are called ____
Cyanobacteria
What compound is most commonly used to solidify the growth medium in Petri dishes?
Agar
Explain two important reasons why the Cow Pox virus was able to work as an effective vaccine for Small Pox.
One reason was that the cow pox virus, even though it was a mild disease, was very similar to the small pox virus. Another reason was the immune response to cowpox gave protection against smallpox.
The appearance of Gram-negative bacteria after decolorization with the decolorizing agent (alcohol) in the Gram stain is:
1)Purple
2)Red/orange
3)Colorless
4)Brown
Colorless
Fluorescence
Allows localization of specific cell proteins
Phase-contrast
Allows visualization of live cells
Transmission electron
Requires staining with heavy metals
Dark field
Only light diffracted by th especimen is visualized
The total magnification of an image by a microscope is the product of the strength of the _____ and the _____
Objective lens and the Ocular lens
Two types of eukaryotic cell organelles that arose via endosymbiosis are:
Mitochondria and Chloroplasts
Photoautotrophs obtain their energy from _____ and their carbon source from _____
light, carbon dioxide
Describe three reasons that Woese chose rRNA as a molecule on which to base a molecular approach to phylogeny.
rRNA is an ancient molecule that all cells have. rRNA has changed very slowly over evolutionary time. rRNA is easily sequenced.
NAD+ can serve as a carrier of____
1)electrons
2)protons
3)electrons and protons
4)electrons and neutrons
5)iron and sulfer
electrons and protons
Prosthetic group
A chemical reactive structure covalently attached to an enzyme
Cytochrome
A protein that accepts and donates electrons
Coenzyme
A chemical reactive structure that transiently associates with an enzyme
Anabolism
The assembly of new cellular building blocks
When ___ -trophs carry out respiration, they transfer ___ from inorganic compounds to terminal electron acceptors.
chemolitho, electrons
During aerobic respiration, ___ is the terminal electron acceptor, and theis acceptor is converted to the product: ___
oxygen, water
In Oxidative phosphorylation, energy from the ____ is used by the enzyme ____ to produce ATP.
proton gradient, ATP synthase
Describe how fermentation and anaerobic respiration achieve one goal in common for the cell. Then describe why anaerobic respiration might be more beneficial for the cell.
Both fermentation and anaerobic respiration result in recycling/oxidation of reduced coenzymes. Anaerobic respiration produces energy (a proton-motive force and/or ATP) while fermentation does not.
