Module 1 Flashcards
The Microbial World
definition: phylogenetic approach to studying evolution
using rRNA sequences
definition: biogeochemistry
transition of chemicals b/w organic and inorganic forms, and oxidized and reduced forms, as part of energy transfer within the ecosystem
microorganisms vs microbes
microbes include viruses
list the macromolecules dry weights in a cell in decreasing orders
polypeptides (50-55), rRNA (15-20), lipids (10), polysaccharides (6-7), DNA (2-5)
who was responsible for the production of oxygen gas at the beginning?
cyanobacteria (~3 billion years ago)
who discovered microorganisms
Robert Hooke (looked at fruiting structure of mold)
who first saw and discovered bacteria
Antonie von Leeuwenhoek
why do we study microorganisms
- fast, inexpensive, and easy to grow
- produce enzymes and other molecules for industrial/medical uses
- fewer genes and single-celled, makes genetic manipulation easier
what are the basic requirements for microbial life
- metabolism
- growth
- reproduction
- genetic variation/evolution
- response/adaption
- homeostasis
who discovered archaea
Carl Woese
which domains contain histones
archaea and eukarya
what RNA polymerase do archaea have
single polymerase, eukaryal-like RNA pol II
what does a reducing atmosphere mean
atmosphere contained many gaseous and dissolved compounds with electrons to donate to redox reactions
what gases would have been present in early Earth conditions
- methane
- carbon monoxide
- carbon dioxide
- cyanide
- hydrogen gas
what is the RNA world hypothesis
RNA could have served to create early life-like “cells”
why is DNA needed when there is RNA
DNA is more stable
what are some features of the earliest microbes
- able to metabolize iron and/or sulfur
- thermophiles
- anaerobic
- able to use light energy
- consume inorganic carbon
what are autotrophs
- primary produces
- fix CO2 into organic molecules
- ingests inorganic carbon, without C-C bonds
what are heterotrophs
- organisms that ingest organic molecules from primary produces
- ingests molecules with C-C bonds
who disproved the theory of spontaneous generation
Louis Pasteur
what are Koch’s postulates
- streak a sample of a diseased animal onto a plate of bacterial growth medium, one organism should be found in diseased animals and not in healthy ones
- obtain pure cultures of the suspected pathogen
- inoculate the healthy animal with the suspected pathogen
- you should be able to identify the suspected pathogen in the newly diseased animal and culture it again
what do Helicobacter pylori cause
stomach ulcers
what does Yersinia pestis cause
bubonic plague
what causes smallpox
the smallpox virus
