Bio 272 Exam 1 with Verified Answers
characteristics associated with living things - Correct Answers -- utilize and transform
energy and matter
- generate and maintain ordered structures
- regulation/homeostasis
- stimulus response
- reproduction
- grow and develop
development of the cell theory - Correct Answers -- hooke: light microscopes/cork
- Leeuwenhoek: protozoa
- Schwann and Schleiden: animals and plants ( division and nucleus structure)
- virchow: cell from cell
signal sequence hypothesis - Correct Answers -protein targeting information is
contained within short polypeptide sequences and these are necessary and sufficient to
confer protein targeting to distance cellular organelles (e.g. ER, mitochondria,
chloroplast, peroxisome, nucleus)
signal sequence - Correct Answers -amino-terminal stretch of 15-20 amino acids that
form a hydrophobic alpha-helix targets proteins to the ER
presequence - Correct Answers -amino-terminal stretch of 18-36 amino acids that form
an amphiphilic alpha-helix targets proteins to mitochondria
- pasteur: disproved spontaneous generation
unifying characteristics of all cells - Correct Answers -- central dogma
- all living organism utilize DNA to encode their "genetic information"
- replication of DNA allows propagation of this "genetic information" to ensuing
generations
- DNA-encoded"information" is transcribed into RNA, which is then translated into
functional protein enzymes
prokaryotes - Correct Answers -- types: bacteria, archaea, cyanobacteria
(photosynthetic)
- sizes: typically 1-10 um
- organelles: few or none
- genome: circular DNA, in cytoplasm
,- RNA and protein: both in cytoplasm
- cytoplasm: simple cytoskeleton: no endocytosis/exocytosis
- cell division: simple binary fission
- organization: mainly unicellular
eukaryotes - Correct Answers -- types: protists, fungi, plants, animals
- size: typically 10-100 um
- organelles: many
- genome: linear DNA, in nucleus
- RNA and protein: RNA synthesized in nucleus , translated in cytoplasm
- cytoplasm: complex cytoskeleton ( intermediate, microtubules, actin filaments)
- cell division: ,mitosis and meiosis
- organization: unicellular and multicellular
prokaryote cell types - Correct Answers -typically spherical, rodlike, or spiral shaped
- often surrounded by tough protective coat (cell wall and capsule)
- most live as unicellular organisms, but some join together to form chains, clusters, or
other organized communities
- extremely diverse cellular metabolisms which can exploit diverse range of habitats
( extremophiles, aerobic anaerobic, etc. )
evolution of prokaryotes - Correct Answers --evolved to catabolize almost anything from
wood to plastics and petroleum
- some can generate organic compounds from inorganic CO2 (photosynthesis) and
inorganic N2
- ancient internalization of prokaryotes are thought to have given rise to mitochondria in
eukaryotes, and chloroplasts in plants
- some plant species, such as legumes, internalize N2-fixing bacteria in specialized '
peribacteriod' structures- perhaps reflecting the current evolution of a third
'endosymbiotic' organelle
eukaryote cell types - Correct Answers -characterized by the presence of a "prominent"
cellular organelle, the nucleus
- generally bigger (10x size and 1000x volume) than prokaryotic cells "cellular
mansions"
- some are unicellular, others organize into elaborate assemblies and organisms
- cytoplasm is complex, with elaborate cytoskeletal arrays, and membrane-bound
cellular compartments
- enlargement and increased complexity of cytoplasm is accompanied by more
specialization of cell division e vents ) not just mitosis, but also meiosis)
where eukaryotes came from - Correct Answers -- prorkaryotes and eukaryotes
diverged early in evolutionary terms
- mitochondria and plastids are not uniformly distributed, suggesting that they may have
been acquired independently
, multicellularity - Correct Answers -eukaryotic cells also organize into multicellular
organism
- cells in these organisms differentiate to perform specialized functions
- these specialized functions often are associated with distinct changes in shape and/or
metabolic activity
cell differentiation - Correct Answers -the process by which embryonic stem cells, which
have the capacity to form all tissues and organs assume a specific developmental fate
in which their morphology and function is fixed
- differentiated cells have the same DNA, but different gens are selectively turned on or
off
totipotent stem cells - Correct Answers -Stem cells that can differentiate into any type of
specialized cells found in organisms of that species.
pluripotent stem cells - Correct Answers -Stem cells that can become almost all types of
tissues and cells in the body.
light microscope - Correct Answers -how we can see cells
- by using visible light we are constrained to imaging objects down to ~200 nm (0.2 um)
resolution due to the physical property of light's wavelength
- commonly used in a wide variety of laboratory application as the standard microscope'
produces an image on a bright background
major difference between light and fluorescence - Correct Answers -the light's path
- light microscopy: light passes directly through the specimen
- fluorescence microscopy: light is absorbed by the specimens and re-emitted at a
different wavelength
generating contrast with microscopes - Correct Answers -many organisms you will
observe under the microscope have a high water content (cells are roughly 70% water
while the remaining 30% are macromolecules)
- phase-contrast optics
- fluorescent probes
- sample fixation
- DIC
phase- contrast optics - Correct Answers -uses refraction and interference caused by
structures in specimen to create high-contrast, high-resolution images without
staining:make it useful for viewing live specimens, and structure such as endospores
and organelles
differential interference contrast (DIC) - Correct Answers -generating contrast using light
microscopes, uses interference patterns to enhance contrast between different feature
of a specimen to produce high-contrast images of living organisms with a 3D
appearance
characteristics associated with living things - Correct Answers -- utilize and transform
energy and matter
- generate and maintain ordered structures
- regulation/homeostasis
- stimulus response
- reproduction
- grow and develop
development of the cell theory - Correct Answers -- hooke: light microscopes/cork
- Leeuwenhoek: protozoa
- Schwann and Schleiden: animals and plants ( division and nucleus structure)
- virchow: cell from cell
signal sequence hypothesis - Correct Answers -protein targeting information is
contained within short polypeptide sequences and these are necessary and sufficient to
confer protein targeting to distance cellular organelles (e.g. ER, mitochondria,
chloroplast, peroxisome, nucleus)
signal sequence - Correct Answers -amino-terminal stretch of 15-20 amino acids that
form a hydrophobic alpha-helix targets proteins to the ER
presequence - Correct Answers -amino-terminal stretch of 18-36 amino acids that form
an amphiphilic alpha-helix targets proteins to mitochondria
- pasteur: disproved spontaneous generation
unifying characteristics of all cells - Correct Answers -- central dogma
- all living organism utilize DNA to encode their "genetic information"
- replication of DNA allows propagation of this "genetic information" to ensuing
generations
- DNA-encoded"information" is transcribed into RNA, which is then translated into
functional protein enzymes
prokaryotes - Correct Answers -- types: bacteria, archaea, cyanobacteria
(photosynthetic)
- sizes: typically 1-10 um
- organelles: few or none
- genome: circular DNA, in cytoplasm
,- RNA and protein: both in cytoplasm
- cytoplasm: simple cytoskeleton: no endocytosis/exocytosis
- cell division: simple binary fission
- organization: mainly unicellular
eukaryotes - Correct Answers -- types: protists, fungi, plants, animals
- size: typically 10-100 um
- organelles: many
- genome: linear DNA, in nucleus
- RNA and protein: RNA synthesized in nucleus , translated in cytoplasm
- cytoplasm: complex cytoskeleton ( intermediate, microtubules, actin filaments)
- cell division: ,mitosis and meiosis
- organization: unicellular and multicellular
prokaryote cell types - Correct Answers -typically spherical, rodlike, or spiral shaped
- often surrounded by tough protective coat (cell wall and capsule)
- most live as unicellular organisms, but some join together to form chains, clusters, or
other organized communities
- extremely diverse cellular metabolisms which can exploit diverse range of habitats
( extremophiles, aerobic anaerobic, etc. )
evolution of prokaryotes - Correct Answers --evolved to catabolize almost anything from
wood to plastics and petroleum
- some can generate organic compounds from inorganic CO2 (photosynthesis) and
inorganic N2
- ancient internalization of prokaryotes are thought to have given rise to mitochondria in
eukaryotes, and chloroplasts in plants
- some plant species, such as legumes, internalize N2-fixing bacteria in specialized '
peribacteriod' structures- perhaps reflecting the current evolution of a third
'endosymbiotic' organelle
eukaryote cell types - Correct Answers -characterized by the presence of a "prominent"
cellular organelle, the nucleus
- generally bigger (10x size and 1000x volume) than prokaryotic cells "cellular
mansions"
- some are unicellular, others organize into elaborate assemblies and organisms
- cytoplasm is complex, with elaborate cytoskeletal arrays, and membrane-bound
cellular compartments
- enlargement and increased complexity of cytoplasm is accompanied by more
specialization of cell division e vents ) not just mitosis, but also meiosis)
where eukaryotes came from - Correct Answers -- prorkaryotes and eukaryotes
diverged early in evolutionary terms
- mitochondria and plastids are not uniformly distributed, suggesting that they may have
been acquired independently
, multicellularity - Correct Answers -eukaryotic cells also organize into multicellular
organism
- cells in these organisms differentiate to perform specialized functions
- these specialized functions often are associated with distinct changes in shape and/or
metabolic activity
cell differentiation - Correct Answers -the process by which embryonic stem cells, which
have the capacity to form all tissues and organs assume a specific developmental fate
in which their morphology and function is fixed
- differentiated cells have the same DNA, but different gens are selectively turned on or
off
totipotent stem cells - Correct Answers -Stem cells that can differentiate into any type of
specialized cells found in organisms of that species.
pluripotent stem cells - Correct Answers -Stem cells that can become almost all types of
tissues and cells in the body.
light microscope - Correct Answers -how we can see cells
- by using visible light we are constrained to imaging objects down to ~200 nm (0.2 um)
resolution due to the physical property of light's wavelength
- commonly used in a wide variety of laboratory application as the standard microscope'
produces an image on a bright background
major difference between light and fluorescence - Correct Answers -the light's path
- light microscopy: light passes directly through the specimen
- fluorescence microscopy: light is absorbed by the specimens and re-emitted at a
different wavelength
generating contrast with microscopes - Correct Answers -many organisms you will
observe under the microscope have a high water content (cells are roughly 70% water
while the remaining 30% are macromolecules)
- phase-contrast optics
- fluorescent probes
- sample fixation
- DIC
phase- contrast optics - Correct Answers -uses refraction and interference caused by
structures in specimen to create high-contrast, high-resolution images without
staining:make it useful for viewing live specimens, and structure such as endospores
and organelles
differential interference contrast (DIC) - Correct Answers -generating contrast using light
microscopes, uses interference patterns to enhance contrast between different feature
of a specimen to produce high-contrast images of living organisms with a 3D
appearance
