MCB 100 FULL EXAM 1 (UIUC) 2025
QUESTIONS AND ANSWERS
Key distinction of microorganisms from other organisms - ANS microorganisms do not form
differentiated tissues
1 mm = ? microns - ANS 1000
1 m = ? mm - ANS 1000
1 micron = ? nm - ANS 1000
"little things" small to large - ANS atoms ==> small molecules (amino acids, nucleotides,
sugars) ==> biological macromolecules (proteins, nucleic acids, polysaccharides, lipids) ==>
subcellular structures (viruses, ribosomes, microtubules) ==> Rickettsia, Chlamydia,
Mycoplasma, and Nanobacteria ==> most bacteria and archaea ==> yeasts and flagellated
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,protozoa ==> typical plant and animal cells, amoebae ==> ciliated protozoa ==> zooplankton
(small multicellular animals)
subcellular aggregates of molecules - ANS viruses, viroids, prions
traits of all living cells - ANS 1. Able to grow and reproduce (can convert nonliving nutrients
into living cytoplasm)
2. Genetic material is DNA
3. Metabolism
4. Able to make or acquire ATP
5. Able to synthesize proteins
6. Bound by an active cell membrane
function of ribosomes - ANS read mRNA and synthesize proteins
traits of viruses - ANS 1. Not cellular organisms
2. Consist of some genetic material, either DNA or RNA, surrounded by a coat of protein
(capsid)
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,3. Some animal viruses have a membrane-like envelope of lipids and proteins, but many viruses
lack this feature
4. Lack ribosomes and tRNAs -- cannot synthesize proteins on their own
5. Contain few or no enzymes -- lack metabolic pathways
6. Lack ATP -- no means of generating ATP
7. Obligate intracellular parasites -- must be inside host cell to have life-like functions
sizes of viruses and bacteria small - large - ANS hemoglobin ==> Poliomyelitis ==> Adenovirus
==> HIV ==> Poxvirus ==> Rickettsia ==> Streptococcus ==> E. coli
have cell wall - ANS 1. Most bacteria
2. Archaea
3. Plants
4. Fungi
5. Algae
lack cell wall - ANS 1. Mycoplasma
2. Animals
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, 3. Protozoa
cell membrane - ANS Lipid bilayer with embedded proteins that acts as the diffusion barrier
around the cell. Semipermeable.
cell wall - ANS Net-like bag of polysaccharides that surrounds the cell and causes it to
maintain a specific shape. Protects the cell from osmotic lysis but is not a barrier to the
diffusion of small molecules.
prokaryotes - ANS no nuclear membrane
bacteria
archaea
eukaryotes - ANS have nuclear membrane
protozoa
fungi
algae
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QUESTIONS AND ANSWERS
Key distinction of microorganisms from other organisms - ANS microorganisms do not form
differentiated tissues
1 mm = ? microns - ANS 1000
1 m = ? mm - ANS 1000
1 micron = ? nm - ANS 1000
"little things" small to large - ANS atoms ==> small molecules (amino acids, nucleotides,
sugars) ==> biological macromolecules (proteins, nucleic acids, polysaccharides, lipids) ==>
subcellular structures (viruses, ribosomes, microtubules) ==> Rickettsia, Chlamydia,
Mycoplasma, and Nanobacteria ==> most bacteria and archaea ==> yeasts and flagellated
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,protozoa ==> typical plant and animal cells, amoebae ==> ciliated protozoa ==> zooplankton
(small multicellular animals)
subcellular aggregates of molecules - ANS viruses, viroids, prions
traits of all living cells - ANS 1. Able to grow and reproduce (can convert nonliving nutrients
into living cytoplasm)
2. Genetic material is DNA
3. Metabolism
4. Able to make or acquire ATP
5. Able to synthesize proteins
6. Bound by an active cell membrane
function of ribosomes - ANS read mRNA and synthesize proteins
traits of viruses - ANS 1. Not cellular organisms
2. Consist of some genetic material, either DNA or RNA, surrounded by a coat of protein
(capsid)
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,3. Some animal viruses have a membrane-like envelope of lipids and proteins, but many viruses
lack this feature
4. Lack ribosomes and tRNAs -- cannot synthesize proteins on their own
5. Contain few or no enzymes -- lack metabolic pathways
6. Lack ATP -- no means of generating ATP
7. Obligate intracellular parasites -- must be inside host cell to have life-like functions
sizes of viruses and bacteria small - large - ANS hemoglobin ==> Poliomyelitis ==> Adenovirus
==> HIV ==> Poxvirus ==> Rickettsia ==> Streptococcus ==> E. coli
have cell wall - ANS 1. Most bacteria
2. Archaea
3. Plants
4. Fungi
5. Algae
lack cell wall - ANS 1. Mycoplasma
2. Animals
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, 3. Protozoa
cell membrane - ANS Lipid bilayer with embedded proteins that acts as the diffusion barrier
around the cell. Semipermeable.
cell wall - ANS Net-like bag of polysaccharides that surrounds the cell and causes it to
maintain a specific shape. Protects the cell from osmotic lysis but is not a barrier to the
diffusion of small molecules.
prokaryotes - ANS no nuclear membrane
bacteria
archaea
eukaryotes - ANS have nuclear membrane
protozoa
fungi
algae
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