Microbes, Aseptic Techniques, Microscopes Flashcards
microbes
any organism that can’t be seen with the naked eye
difference between a prokaryote and eukaryote cell
prokaryotes lack a nucleus (DNA floating in cytoplasm)
“first” cell type
prokaryote
characteristics of prokaryotes
low life expectancy, mutates fast, hard to control, lacks most organelles
organelles that prokaryotes do have
ribosomes, cell membrane, cell wall
what can be used to identify types of bacteria
cell wall
characteristics of eukaryotes
more developed cell with a nucleus and specialized organelles
two domains of prokaryotes
Bacteria and Archaea
archaea
live in hostile environments, anaerobic
anaerobic
does not require oxygen
how long has bacteria been around
3.7 billion years, they’ve adapted to almost every niche
what do microbes do
cause disease, help their host, maintain ecosystems, alter climate
disease causing bacteria are called
pathogens
types of pathogens
Bacteria, viruses, protozoa, fungi, helminths
how do microbes help their hosts
aid in digestion, make vitamins, detoxify chemicals, develop the immune system, fight off invaders
how do bacteria maintain ecosystems
cycle nutrients, cycle metals, decompose, fix O2 CO2 and N2, food source, bioremediation
how do bacteria alter climate
seed clouds, produce O2, sequester CO2
why study microorganisms
they are the most abundant, diverse, ancient, and fastest evolving organisms on Earth, there is still much to learn, an opportunity to study processes common to all life, prepares us to fight disease, microbial enzymes are useful, used in genetic engineering research
microbial enzymes help us make
biofuels, foods, meds, and industrial products
What is an aseptic technique?
a method followed to prevent contamination
three ways to reduce contamination
sterilization, disinfect, antiseptic
sterilization
kill off all bacteria
main method of sterilization
heat
what must be sterilized
anything that touches bacteria
disinfect
harsh chemicals that are harmful to cells
what are disinfectants used on
inanimate objects
antiseptics
chemicals safe to use on living cells
common antiseptic
ethyl alcohol
what does ethyl alcohol do
dehydrates bacteria
what do disinfectants and antiseptics have in common
they DO NOT kill all bacteria, only reduces risk of contamination
agar
medium used to grow bacterial cultures
what is agar composed of
nutrients and water
colony characteristics
color, size, form, elevation, apperance
inoculate
transfer bacteria from one medium to another
general rule for using a compound microscope
multiply objective magnification by eyepiece magnification
