MCB 104 Exam 2#1 Questions with correct answers
key distinction of microorganisms from other organisms - ✔✔microorganisms do
not form differentiated tissues
1 mm = ? microns - ✔✔1000
1 m = ? mm - ✔✔1000
1 micron = ? nm - ✔✔1000
"little things" small to large - ✔✔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 protozoa ==> typical plant
and animal cells, amoebae ==> ciliated protozoa ==> zooplankton (small
multicellular animals)
subcellular aggregates of molecules - ✔✔viruses, viroids, prions
traits of all living cells - ✔✔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 - ✔✔read mRNA and synthesize proteins
traits of viruses - ✔✔1. Not cellular organisms
2. Consist of some genetic material, either DNA or RNA, surrounded by a coat of
protein (capsid)
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 - ✔✔hemoglobin ==> Poliomyelitis ==>
Adenovirus ==> HIV ==> Poxvirus ==> Rickettsia ==> Streptococcus ==> E. coli
have cell wall - ✔✔1. Most bacteria
2. Archaea
3. Plants
4. Fungi
5. Algae
lack cell wall - ✔✔1. Mycoplasma
,2. Animals
3. Protozoa
cell membrane - ✔✔Lipid bilayer with embedded proteins that acts as the
diffusion barrier around the cell. Semipermeable.
cell wall - ✔✔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 - ✔✔no nuclear membrane
bacteria
archaea
eukaryotes - ✔✔have nuclear membrane
protozoa
fungi
algae
eukaryote ribosome size - ✔✔80S
prokaryote ribosome size - ✔✔70S
, structures not found in prokaryotes - ✔✔nuclear membrane, endoplasmic
reticulum, mitochondria, chloroplasts, membrane-bound organelles,
cytoskeleton, phagolysosomes, snRNPs
chromosome number and shape - eukaryotes - ✔✔plural
linear
chromosome number and shape - prokaryotes - ✔✔single
circular
size - eukaryotes - ✔✔mostly 4-20mm
size - prokaryotes - ✔✔mostly 0.5-3mm
fungi - ✔✔Eukaryotic
Cell wall - chitin
Not photosynthetic
Nutrient molecules absorbed by osmosis
Both sexual and asexual reproduction
Most have mitochondria
Most prefer aerobic conditions
protozoa - ✔✔Eukaryotic
No cell wall
key distinction of microorganisms from other organisms - ✔✔microorganisms do
not form differentiated tissues
1 mm = ? microns - ✔✔1000
1 m = ? mm - ✔✔1000
1 micron = ? nm - ✔✔1000
"little things" small to large - ✔✔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 protozoa ==> typical plant
and animal cells, amoebae ==> ciliated protozoa ==> zooplankton (small
multicellular animals)
subcellular aggregates of molecules - ✔✔viruses, viroids, prions
traits of all living cells - ✔✔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 - ✔✔read mRNA and synthesize proteins
traits of viruses - ✔✔1. Not cellular organisms
2. Consist of some genetic material, either DNA or RNA, surrounded by a coat of
protein (capsid)
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 - ✔✔hemoglobin ==> Poliomyelitis ==>
Adenovirus ==> HIV ==> Poxvirus ==> Rickettsia ==> Streptococcus ==> E. coli
have cell wall - ✔✔1. Most bacteria
2. Archaea
3. Plants
4. Fungi
5. Algae
lack cell wall - ✔✔1. Mycoplasma
,2. Animals
3. Protozoa
cell membrane - ✔✔Lipid bilayer with embedded proteins that acts as the
diffusion barrier around the cell. Semipermeable.
cell wall - ✔✔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 - ✔✔no nuclear membrane
bacteria
archaea
eukaryotes - ✔✔have nuclear membrane
protozoa
fungi
algae
eukaryote ribosome size - ✔✔80S
prokaryote ribosome size - ✔✔70S
, structures not found in prokaryotes - ✔✔nuclear membrane, endoplasmic
reticulum, mitochondria, chloroplasts, membrane-bound organelles,
cytoskeleton, phagolysosomes, snRNPs
chromosome number and shape - eukaryotes - ✔✔plural
linear
chromosome number and shape - prokaryotes - ✔✔single
circular
size - eukaryotes - ✔✔mostly 4-20mm
size - prokaryotes - ✔✔mostly 0.5-3mm
fungi - ✔✔Eukaryotic
Cell wall - chitin
Not photosynthetic
Nutrient molecules absorbed by osmosis
Both sexual and asexual reproduction
Most have mitochondria
Most prefer aerobic conditions
protozoa - ✔✔Eukaryotic
No cell wall
