MICR 271 Exam Questions| Already
Answered| GRADED A+
Three domains of life - ANSWER-Bacteria, Archaea, Eukaryota
If a eukaryote has a membrane-enclosed nucleus, a prokaryote has: - ANSWER-a nucleoid, not
membrane enclosed
If a eukaryote has lysosomes/peroxisomes, a prokaryote has: - ANSWER-not present
If a eukaryote has an endoplasmic reticulum/golgi apparatus, a prokaryote has: - ANSWER-not present
If a eukaryote has a mitochondria, a prokaryote has: - ANSWER-not present
Bacteria - ANSWER-Domain of unicellular prokaryotes that have cell walls containing peptidoglycan
Archaea - ANSWER-Domain of unicellular prokaryotes that have cell walls that do not contain
peptidoglycan
Eukaryota - ANSWER-Domain of organisms that contain a nucleus and other membrane enclosed
organelles
endosymbiont hypothesis - ANSWER-eukaryotes evolved from prokaryotes, based on the similarities
found between bacteria and mitochondria
Symbiosis - ANSWER-the living together to close association of two dissimilar organisms, each being
known as a symbiont
Differences between mitchondria+chloroplast and other organelles - ANSWER-contain their own DNA
and have a distinct translation system
,a-proteobacteria - ANSWER-a subgroup of proteobacteria, which are a large group of eubacteria,
primarily Gram-negative, that 16S rRNA sequence comparisons show to be phylogenetically related
Archezoan Scenario - ANSWER-A primitive amitochondrial eukaryote cell phagocytosed as an a-
protobacterium - leading to the evolution of the mitochondrion
symbiogenesis scenario - ANSWER-A single endosymbiotic event involving the uptake of an a-
protobacterium by an archaeal cell led to the generation of the mitochondria, followed by the evolution
of the nucleus and compartmentalization of the eukaryotic cell
Phylogeny - ANSWER-the evolutionary history of a group of organisms
Phylogenetic tree of life - ANSWER-compares the rRNA sequences between organisms
Comparing the domains of life: nucleus - ANSWER-bacteria: no
archaea: no
eukaryota: yes
Comparing the domains of life: RNA polymerase - ANSWER-bacteria: 3-4 subunits
archaea: 8-12 subunits
eukaryota: 12-14 subunits
Comparing the domains of life: Ribosomes - ANSWER-bacteria: 70S
archaea: 70S
eukaryota: 80S
Comparing the domains of life: cell wall - ANSWER-bacteria: murein (peptidoglycan)
archaea: no murein
euakryota: no murein
, Phylogenomic tree of life - ANSWER-Tree of life based on complete genomes of organisms
horizontal gene transfer - ANSWER-the movement of genetic material between organisms other than via
vertical transmission (parent to child)
Obligate intracellular parasite - ANSWER-A parasite that cannot reproduce outside of a host cell; their
reproduction is entirely reliant on intracellular resources
- e.g. viruses
Virion - ANSWER-the form a virus takes when not inside the host - a complete virus particle
Composition of a virion - ANSWER-1. genetic material - DNA or RNA
2. capsid - the protein coat
3. envelope - some viruses have a layer of lipids surrounding the protein coat
Virus-first theory - ANSWER-viruses are ancestral to cells
- viruses evolved from mixtures of macromolecules before the first cells appeared on earth
- viruses existed as self-replicating units in a pre-cellular world
Escape theory - ANSWER-cells came before viruses
- viruses are derived from bits of cellular RNA and/or DNA fragments that leaked from cells
- when these fragments acquire a protein coat they can become independent entities with the ability to
interact with other cells
Reduction theory - ANSWER-cells came before viruses
- viruses come from small primordial cells that lost cellular elements over the course of evolution, but
maintained their genetic material and certain elements needed for replication
Viral genome integration or lysogeny - ANSWER-When a virus is capable of incorporating into the host
genome
Answered| GRADED A+
Three domains of life - ANSWER-Bacteria, Archaea, Eukaryota
If a eukaryote has a membrane-enclosed nucleus, a prokaryote has: - ANSWER-a nucleoid, not
membrane enclosed
If a eukaryote has lysosomes/peroxisomes, a prokaryote has: - ANSWER-not present
If a eukaryote has an endoplasmic reticulum/golgi apparatus, a prokaryote has: - ANSWER-not present
If a eukaryote has a mitochondria, a prokaryote has: - ANSWER-not present
Bacteria - ANSWER-Domain of unicellular prokaryotes that have cell walls containing peptidoglycan
Archaea - ANSWER-Domain of unicellular prokaryotes that have cell walls that do not contain
peptidoglycan
Eukaryota - ANSWER-Domain of organisms that contain a nucleus and other membrane enclosed
organelles
endosymbiont hypothesis - ANSWER-eukaryotes evolved from prokaryotes, based on the similarities
found between bacteria and mitochondria
Symbiosis - ANSWER-the living together to close association of two dissimilar organisms, each being
known as a symbiont
Differences between mitchondria+chloroplast and other organelles - ANSWER-contain their own DNA
and have a distinct translation system
,a-proteobacteria - ANSWER-a subgroup of proteobacteria, which are a large group of eubacteria,
primarily Gram-negative, that 16S rRNA sequence comparisons show to be phylogenetically related
Archezoan Scenario - ANSWER-A primitive amitochondrial eukaryote cell phagocytosed as an a-
protobacterium - leading to the evolution of the mitochondrion
symbiogenesis scenario - ANSWER-A single endosymbiotic event involving the uptake of an a-
protobacterium by an archaeal cell led to the generation of the mitochondria, followed by the evolution
of the nucleus and compartmentalization of the eukaryotic cell
Phylogeny - ANSWER-the evolutionary history of a group of organisms
Phylogenetic tree of life - ANSWER-compares the rRNA sequences between organisms
Comparing the domains of life: nucleus - ANSWER-bacteria: no
archaea: no
eukaryota: yes
Comparing the domains of life: RNA polymerase - ANSWER-bacteria: 3-4 subunits
archaea: 8-12 subunits
eukaryota: 12-14 subunits
Comparing the domains of life: Ribosomes - ANSWER-bacteria: 70S
archaea: 70S
eukaryota: 80S
Comparing the domains of life: cell wall - ANSWER-bacteria: murein (peptidoglycan)
archaea: no murein
euakryota: no murein
, Phylogenomic tree of life - ANSWER-Tree of life based on complete genomes of organisms
horizontal gene transfer - ANSWER-the movement of genetic material between organisms other than via
vertical transmission (parent to child)
Obligate intracellular parasite - ANSWER-A parasite that cannot reproduce outside of a host cell; their
reproduction is entirely reliant on intracellular resources
- e.g. viruses
Virion - ANSWER-the form a virus takes when not inside the host - a complete virus particle
Composition of a virion - ANSWER-1. genetic material - DNA or RNA
2. capsid - the protein coat
3. envelope - some viruses have a layer of lipids surrounding the protein coat
Virus-first theory - ANSWER-viruses are ancestral to cells
- viruses evolved from mixtures of macromolecules before the first cells appeared on earth
- viruses existed as self-replicating units in a pre-cellular world
Escape theory - ANSWER-cells came before viruses
- viruses are derived from bits of cellular RNA and/or DNA fragments that leaked from cells
- when these fragments acquire a protein coat they can become independent entities with the ability to
interact with other cells
Reduction theory - ANSWER-cells came before viruses
- viruses come from small primordial cells that lost cellular elements over the course of evolution, but
maintained their genetic material and certain elements needed for replication
Viral genome integration or lysogeny - ANSWER-When a virus is capable of incorporating into the host
genome
