BIO 215 EXAM 1 UPDATED ACTUAL
Exam Questions and CORRECT Answers
Identify characteristics of living things that distinguish them from non-living things. -
CORRECT ANSWER - There are 9 characteristics of living things that distinguish them
from non-living things.
1. Organization
2.Evolution of populations
3. DNA
4. Reproduction
5. Response to environment
6. Metabolism
7. Homeostasis
8. Contain one or more cells.
Give a brief overview of the historical events that contributed to modern cell biology. Recall the
associated names and dates involved in the events discussed in class. - CORRECT
ANSWER - Cells were first observed in 1665 by Robert Hooke. He is credited with
coining the term "cell" in Micrographia. After 1665 there were not many discoveries in cell
biology because they were limited by optical instruments (limited resolving power of
microscopes & a lack of detail) and their way of thinking (more observation, less asking 'why').
1830's there was advancement in optics & in 1831, Robert Brown described the nucleus.
1838 : Schleiden & Schwann put forth the 'Cell Theory'.
Cell Theory - Schwann (1839)
1) The cell is the unit of structure, physiology, and organization in living things.
2) The cell retains a dual existence as a distinct entity and a building block in the construction of
organisms. 3) Cells form by free-cell formation, similar to the formation of crystals
,#3 was wrong and revised by Virchow in 1855. Replaced #3 with "All cells arise from only
preexisting cells".
Summarize the currently accepted cell theory. - CORRECT ANSWER - 1) The cell is a
unit of structure, physiology, and organization in living things
2)The cell retains a dual existence as a distinct entity and a building block in the construction of
organisms.
3)All cells arise from only preexisting cells
Describe the 3 domains of life. - CORRECT ANSWER - Bacteria = Prokaryotes
Archaea = Prokaryotes, many extremophiles
Eukarya = Eukaryotes (Protists, plants, fungi, animals)
Who is credited with redrawing the tree of life into 3 domains? - CORRECT ANSWER -
Carle Woese & George Fox.
Describe the evidence used to reclassify organisms into the 3 domains. Why were rRNA gene
sequences used for to analyze phylogenetic relationships? - CORRECT ANSWER - Carle
and Woese and George Fox redrew phylogenetic relationships based on analysis of rRNA gene
sequences.
They used rRNA because
1) all cells require rRNA
2) they change very slowly over time (not much room for variation bc their sequence is so
closely related to its function). Bc of this, any slight changes in sequence reflect an evolutionary
"step." rNA can be used to establish evolutionary relationships between all species.
3) conserved regions enable easy in virto replication
What information did we learn from the analysis of the rRNA gene sequences pioneered by
Woese and Fox? - CORRECT ANSWER - There were two separate prokaryote groups
(Bacteria and Achaean domains) that were actually very different from each other, although
before that they had always been grouped together bc they are prokaryotes.
, Suggested that eukaryotes and archaea are actually more closely related to each other than to
bacteria
Allowed a better understanding of how protists should be organized
Revealed how incorrect it was to classify them all together in one kingdom
Some protists are not even closely related at all
What is a protist? Why is it no longer correct to classify all protists together into one
phylogenetic group? - CORRECT ANSWER - A diverse grouping of eukaryotic
organisms. Many diverse lineages of various eukaryotic organisms. Can be unicellular or
multicellular. They are so diverse that they are not closely related enough to group them into one
group.
Are viruses considered living organisms? Why or why not? Explain. - CORRECT
ANSWER - No, they do not exhibit multiple characteristics of living things. These
characteristics are : growth/development, response to environment, metabolism, homeostasis,
and they do not contain one or more cells.
Describe the fundamental differences between eukaryotic and prokaryotic cells. - CORRECT
ANSWER - Prokaryotes lack the internal complexity seen in Eukaryotes and are on
average much smaller than eukaryotes. They also lack a nucleus but instead have a "nucleoid
region."
Eukaryotic cells have a nucleus and various membrane bound organelles. They are also much
larger than prokaryotes on average.
Describe the structural features shared by all cells. - CORRECT ANSWER - Surrounded
by lipid-based plasma membrane
Metabolic machinery
DNA as hereditary information
Ribosome as protein-synthesizing machinery
Convert between the different SI/metric prefixes. Recall the prefixes appropriate for describing
cells, subcellular structures and molecules. Convert between standard notation and scientific
Exam Questions and CORRECT Answers
Identify characteristics of living things that distinguish them from non-living things. -
CORRECT ANSWER - There are 9 characteristics of living things that distinguish them
from non-living things.
1. Organization
2.Evolution of populations
3. DNA
4. Reproduction
5. Response to environment
6. Metabolism
7. Homeostasis
8. Contain one or more cells.
Give a brief overview of the historical events that contributed to modern cell biology. Recall the
associated names and dates involved in the events discussed in class. - CORRECT
ANSWER - Cells were first observed in 1665 by Robert Hooke. He is credited with
coining the term "cell" in Micrographia. After 1665 there were not many discoveries in cell
biology because they were limited by optical instruments (limited resolving power of
microscopes & a lack of detail) and their way of thinking (more observation, less asking 'why').
1830's there was advancement in optics & in 1831, Robert Brown described the nucleus.
1838 : Schleiden & Schwann put forth the 'Cell Theory'.
Cell Theory - Schwann (1839)
1) The cell is the unit of structure, physiology, and organization in living things.
2) The cell retains a dual existence as a distinct entity and a building block in the construction of
organisms. 3) Cells form by free-cell formation, similar to the formation of crystals
,#3 was wrong and revised by Virchow in 1855. Replaced #3 with "All cells arise from only
preexisting cells".
Summarize the currently accepted cell theory. - CORRECT ANSWER - 1) The cell is a
unit of structure, physiology, and organization in living things
2)The cell retains a dual existence as a distinct entity and a building block in the construction of
organisms.
3)All cells arise from only preexisting cells
Describe the 3 domains of life. - CORRECT ANSWER - Bacteria = Prokaryotes
Archaea = Prokaryotes, many extremophiles
Eukarya = Eukaryotes (Protists, plants, fungi, animals)
Who is credited with redrawing the tree of life into 3 domains? - CORRECT ANSWER -
Carle Woese & George Fox.
Describe the evidence used to reclassify organisms into the 3 domains. Why were rRNA gene
sequences used for to analyze phylogenetic relationships? - CORRECT ANSWER - Carle
and Woese and George Fox redrew phylogenetic relationships based on analysis of rRNA gene
sequences.
They used rRNA because
1) all cells require rRNA
2) they change very slowly over time (not much room for variation bc their sequence is so
closely related to its function). Bc of this, any slight changes in sequence reflect an evolutionary
"step." rNA can be used to establish evolutionary relationships between all species.
3) conserved regions enable easy in virto replication
What information did we learn from the analysis of the rRNA gene sequences pioneered by
Woese and Fox? - CORRECT ANSWER - There were two separate prokaryote groups
(Bacteria and Achaean domains) that were actually very different from each other, although
before that they had always been grouped together bc they are prokaryotes.
, Suggested that eukaryotes and archaea are actually more closely related to each other than to
bacteria
Allowed a better understanding of how protists should be organized
Revealed how incorrect it was to classify them all together in one kingdom
Some protists are not even closely related at all
What is a protist? Why is it no longer correct to classify all protists together into one
phylogenetic group? - CORRECT ANSWER - A diverse grouping of eukaryotic
organisms. Many diverse lineages of various eukaryotic organisms. Can be unicellular or
multicellular. They are so diverse that they are not closely related enough to group them into one
group.
Are viruses considered living organisms? Why or why not? Explain. - CORRECT
ANSWER - No, they do not exhibit multiple characteristics of living things. These
characteristics are : growth/development, response to environment, metabolism, homeostasis,
and they do not contain one or more cells.
Describe the fundamental differences between eukaryotic and prokaryotic cells. - CORRECT
ANSWER - Prokaryotes lack the internal complexity seen in Eukaryotes and are on
average much smaller than eukaryotes. They also lack a nucleus but instead have a "nucleoid
region."
Eukaryotic cells have a nucleus and various membrane bound organelles. They are also much
larger than prokaryotes on average.
Describe the structural features shared by all cells. - CORRECT ANSWER - Surrounded
by lipid-based plasma membrane
Metabolic machinery
DNA as hereditary information
Ribosome as protein-synthesizing machinery
Convert between the different SI/metric prefixes. Recall the prefixes appropriate for describing
cells, subcellular structures and molecules. Convert between standard notation and scientific
