MIBO 2500 exam 1 with 100% correct
answers 2024
Microbes - ANSWER-Microbes are organisms and acellular (things that cannot
reproduce on their own) agents too small to be seen by the unaided eye
Antonie van Leeuwenhoek (1632-1723) - ANSWER-- Built single-lens magnifiers,
complete with sample holder and focus adjustment
- First to observe single-celled microbes
- He called them "small animals" (animalcules)
- Most likely observing fungus and large bacterial cells
Francesco Redi (1626-1697) - ANSWER--discredited spontaneous generation by
observing 3 containers of meat
John Needham (1713-1781) - ANSWER-- Nutrient rich Broth boiled, then
cooled at room temp → sealed → cloudy broth
- Evidence animalcules were growing in broth
- Stated this proved spontaneous generation to be true
- Concerns with conclusion= animalcules could come from air, seal, flask, etc... did not
have technology to completely sterilize
Lazarro Spallanzani (1729-1799) - ANSWER-- Broth boiled, then cooled at
room temp (not capped)→ wait→ cloudy
- Broth boiled, then cooked at room temp capped immediately→wait →clear
- Stated this disproved spontaneous generation
Louis Pasteur (1822-1895) - ANSWER-- Credited with disproving spontaneous
generation
- Proved biogenesis
- Microbes came from the air but not created by the air itself
- Broth heated in swan neck flask → waited → clear
- Broth heated in swan neck flask → wait → broke neck of flask→ cloudy
- Swan neck allows air to enter flask, but keeps microbes from entering
, Robert Koch (1800s) - ANSWER--noted animolecules in tissue of sick animals and
patients, thought they may be causing disease
Koch's postulates - ANSWER-1. In order to know if a microbe is causing an illness, it
must be present in every case, and absent from healthy hosts
2. Grow in pure culture (should be able to separate it from sick tissue and grow it by
itself)
3. Introduce to new host=same disease (should be able to give pure culture to healthy
host, and host get sick)
4. Must be able to isolate from 2nd host
Bacteria - ANSWER-- Prokaryotic
-Unicellular
- No membrane bound organelles
- Ribosomal RNA sequences unique to the group
- Peptidoglycan in cell wall
- Typical size range= 0.3-2 micromenters
Archaea - ANSWER-- Prokaryotic
- Unicellular
- No membrane bound organelles
- Ribosomal RNA sequences unique to the group
- No Peptidoglycan in cell wall
- Typical size range= 0.3-2 micromenters
Eukarya - ANSWER-- Eukaryotic
- Unicellular or multicellular
- Membrane bound organelles
- Ribosomal RNA sequences unique to the group
- No peptidoglycan in cell wall
- Typical size range= 5-50micromenters
Resolution - ANSWER-the ability to distinguish small objects close together
Magnification - ANSWER-an enlarged image of an object
Contrast - ANSWER-the difference in color intensity between an object and its
background
answers 2024
Microbes - ANSWER-Microbes are organisms and acellular (things that cannot
reproduce on their own) agents too small to be seen by the unaided eye
Antonie van Leeuwenhoek (1632-1723) - ANSWER-- Built single-lens magnifiers,
complete with sample holder and focus adjustment
- First to observe single-celled microbes
- He called them "small animals" (animalcules)
- Most likely observing fungus and large bacterial cells
Francesco Redi (1626-1697) - ANSWER--discredited spontaneous generation by
observing 3 containers of meat
John Needham (1713-1781) - ANSWER-- Nutrient rich Broth boiled, then
cooled at room temp → sealed → cloudy broth
- Evidence animalcules were growing in broth
- Stated this proved spontaneous generation to be true
- Concerns with conclusion= animalcules could come from air, seal, flask, etc... did not
have technology to completely sterilize
Lazarro Spallanzani (1729-1799) - ANSWER-- Broth boiled, then cooled at
room temp (not capped)→ wait→ cloudy
- Broth boiled, then cooked at room temp capped immediately→wait →clear
- Stated this disproved spontaneous generation
Louis Pasteur (1822-1895) - ANSWER-- Credited with disproving spontaneous
generation
- Proved biogenesis
- Microbes came from the air but not created by the air itself
- Broth heated in swan neck flask → waited → clear
- Broth heated in swan neck flask → wait → broke neck of flask→ cloudy
- Swan neck allows air to enter flask, but keeps microbes from entering
, Robert Koch (1800s) - ANSWER--noted animolecules in tissue of sick animals and
patients, thought they may be causing disease
Koch's postulates - ANSWER-1. In order to know if a microbe is causing an illness, it
must be present in every case, and absent from healthy hosts
2. Grow in pure culture (should be able to separate it from sick tissue and grow it by
itself)
3. Introduce to new host=same disease (should be able to give pure culture to healthy
host, and host get sick)
4. Must be able to isolate from 2nd host
Bacteria - ANSWER-- Prokaryotic
-Unicellular
- No membrane bound organelles
- Ribosomal RNA sequences unique to the group
- Peptidoglycan in cell wall
- Typical size range= 0.3-2 micromenters
Archaea - ANSWER-- Prokaryotic
- Unicellular
- No membrane bound organelles
- Ribosomal RNA sequences unique to the group
- No Peptidoglycan in cell wall
- Typical size range= 0.3-2 micromenters
Eukarya - ANSWER-- Eukaryotic
- Unicellular or multicellular
- Membrane bound organelles
- Ribosomal RNA sequences unique to the group
- No peptidoglycan in cell wall
- Typical size range= 5-50micromenters
Resolution - ANSWER-the ability to distinguish small objects close together
Magnification - ANSWER-an enlarged image of an object
Contrast - ANSWER-the difference in color intensity between an object and its
background
