Biology 1002B: UWO Final Exam
Questions with Guaranteed Pass
Solutions 2026 Updated.
Label the Chlamydomonas cell - Answer Chloroplast - Includes chlorophyll that uses light
energy to convert CO2 into sugar.
Eyespot - It uses the eyespot to gather information about its environment.
Flagella -
Is Chlamydomonas haplontic or diplontic - Answer Haplontic - the life cycle is dominated by
n (mitosis and growth occurs in the haploid form).
How Chlamy grows - Answer It grows most during the G1 phase of cell division
- The commitment stage is where chlamy has grown enough to a certain size to be able to
divide.
- Once it reaches the S/M phase, it can divide asexually
Growth dependent vs. Growth independent (in chlamy cells) - Answer Before the
commitment stage is reached, chlamy cells are dependent on growth. Once the threshold is
reached, the cell is committed to divide, but may still grow (growth is independent of the cell).
** Cells are able to get larger after the commitment stage, but it's not required for cell division.
**
Different phases in the Chlamy growth curve - Answer Lag phase - cells are growing very
slowly
Exponential phase - highest growth rate (we use this to calculate the growth rate/doubling time)
Stationary phase - cells stop dividing completely
Phylogeny of Chlamy - Answer -Considered part of the green algae family
-Have chloroplasts (they are photosynthetic)
-Diverged from plants (more closely related to plants rather than humans, even though they are
the only ones that have eukaryotic flagella. This is also supported by an analysis of the proteins
showing that chlamy is 10% related to humans vs. 26% related to plants).
Why are chlamydomonas considered model systems? Also, describe different types of
ciliopathies. - Answer They are able to be used to identify diseases in humans related to
flagella and cilia - called ciliopathies.
,An example of ciliopathies in MOTILE cilia include, defects in sperm caused by flagella not being
able to move, resulting in the sperm not able to fertilize the egg properly (infertility).
An example of ciliopathies in NON-MOTILE ciliopathies include, defects in sensory cilia caused
by sensory proteins not functioning properly (hearing loss).
Types of proteins found in only chlamy and human cells - Answer -Opsin
Types of proteins found in only chlamy and plant cells - Answer -Proteins involved in
biosynthesis of chlorophyll
Types of proteins found in all three, chlamy, plant and human cells - Answer -Hexokinase
-Spliceosome proteins
-Signal peptides
-Ribosomal proteins
What is phototaxis - Answer The cell moving in response to light
-Positive phototaxis is moving towards the light
-Negative phototaxis is moving away from the light
When these cells are mutated causing a loss in phototaxis, they are considered no longer
phototactic.
What is channelrhodopsin - Answer -A photoreceptor that sits on the plasma membrane.
-It's a light-gated ion channel which controls phototaxis (absorption of light causes gate to open
and allow protons to move down the gradient towards the negative inside of the cell). - known
as depolarizing the membrane.
-Made up of protein (opsin) and pigment (retinal).
What colour light does retinal absorb - Answer Absorbs strongly in the blue light.
What colour does chlorophyll absorb - Answer Absorbs blue light (higher excited state) AND
red light (lower excited state).
-Green gets passed through/bounced off giving plants its green colour.
, What is photoisomerization of channelrhodopsin - Answer When the protein changes
conformation in response to retinal absorbing a photon of light.
-Going from trans to cis conformation
What happens to retinal vs photosystems when exposed to light - Answer Retinal undergoes
cis-trans isomerization
Photosystems undergo oxidation
Describe the steps of optogenetics in mice - Answer 1. Add mouse promoter to a gene
encoding chlamydomonas opsin (channelrhodopsin)
2. Insert this construct into a virus
3. Inject the virus into the mouse which affects the mouse brain cells which gets inserted into
the mouse's genome. (Now channelrhodopsin is sitting on the plasma membrane).
4. Insert a fibre-optic cable into the brain
5. Shine BLUE light which opens the ion channels in neurons.
What is LUCA - Answer Stands for the last universal common ancestor and is NOT the first
organism to ever exist, but the most recent one.
What are the 3 stages of prebiotic evolution - Answer 1. Geophysical - composition of Earth
and atmosphere
2. Chemical - building blocks of life being synthesized
3. Biological - building blocks organize into living cells
What is a protein - Answer -Made up of amino acids
-Has a complex tertiary structure
-Variable stability
-Has catalytic ability as an enzyme
What is DNA - Answer -Made up of four 2' deoxy nucleotides (A,T,C,G)
-Has a double helix conformation
-Very stable
-No catalytic ability (stores genomes)
What is RNA - Answer -Four nucleotides (A,U,G,C)
-Has a complex structure due to intramolecular hydrogen bonding)
-Less stable than DNA
Questions with Guaranteed Pass
Solutions 2026 Updated.
Label the Chlamydomonas cell - Answer Chloroplast - Includes chlorophyll that uses light
energy to convert CO2 into sugar.
Eyespot - It uses the eyespot to gather information about its environment.
Flagella -
Is Chlamydomonas haplontic or diplontic - Answer Haplontic - the life cycle is dominated by
n (mitosis and growth occurs in the haploid form).
How Chlamy grows - Answer It grows most during the G1 phase of cell division
- The commitment stage is where chlamy has grown enough to a certain size to be able to
divide.
- Once it reaches the S/M phase, it can divide asexually
Growth dependent vs. Growth independent (in chlamy cells) - Answer Before the
commitment stage is reached, chlamy cells are dependent on growth. Once the threshold is
reached, the cell is committed to divide, but may still grow (growth is independent of the cell).
** Cells are able to get larger after the commitment stage, but it's not required for cell division.
**
Different phases in the Chlamy growth curve - Answer Lag phase - cells are growing very
slowly
Exponential phase - highest growth rate (we use this to calculate the growth rate/doubling time)
Stationary phase - cells stop dividing completely
Phylogeny of Chlamy - Answer -Considered part of the green algae family
-Have chloroplasts (they are photosynthetic)
-Diverged from plants (more closely related to plants rather than humans, even though they are
the only ones that have eukaryotic flagella. This is also supported by an analysis of the proteins
showing that chlamy is 10% related to humans vs. 26% related to plants).
Why are chlamydomonas considered model systems? Also, describe different types of
ciliopathies. - Answer They are able to be used to identify diseases in humans related to
flagella and cilia - called ciliopathies.
,An example of ciliopathies in MOTILE cilia include, defects in sperm caused by flagella not being
able to move, resulting in the sperm not able to fertilize the egg properly (infertility).
An example of ciliopathies in NON-MOTILE ciliopathies include, defects in sensory cilia caused
by sensory proteins not functioning properly (hearing loss).
Types of proteins found in only chlamy and human cells - Answer -Opsin
Types of proteins found in only chlamy and plant cells - Answer -Proteins involved in
biosynthesis of chlorophyll
Types of proteins found in all three, chlamy, plant and human cells - Answer -Hexokinase
-Spliceosome proteins
-Signal peptides
-Ribosomal proteins
What is phototaxis - Answer The cell moving in response to light
-Positive phototaxis is moving towards the light
-Negative phototaxis is moving away from the light
When these cells are mutated causing a loss in phototaxis, they are considered no longer
phototactic.
What is channelrhodopsin - Answer -A photoreceptor that sits on the plasma membrane.
-It's a light-gated ion channel which controls phototaxis (absorption of light causes gate to open
and allow protons to move down the gradient towards the negative inside of the cell). - known
as depolarizing the membrane.
-Made up of protein (opsin) and pigment (retinal).
What colour light does retinal absorb - Answer Absorbs strongly in the blue light.
What colour does chlorophyll absorb - Answer Absorbs blue light (higher excited state) AND
red light (lower excited state).
-Green gets passed through/bounced off giving plants its green colour.
, What is photoisomerization of channelrhodopsin - Answer When the protein changes
conformation in response to retinal absorbing a photon of light.
-Going from trans to cis conformation
What happens to retinal vs photosystems when exposed to light - Answer Retinal undergoes
cis-trans isomerization
Photosystems undergo oxidation
Describe the steps of optogenetics in mice - Answer 1. Add mouse promoter to a gene
encoding chlamydomonas opsin (channelrhodopsin)
2. Insert this construct into a virus
3. Inject the virus into the mouse which affects the mouse brain cells which gets inserted into
the mouse's genome. (Now channelrhodopsin is sitting on the plasma membrane).
4. Insert a fibre-optic cable into the brain
5. Shine BLUE light which opens the ion channels in neurons.
What is LUCA - Answer Stands for the last universal common ancestor and is NOT the first
organism to ever exist, but the most recent one.
What are the 3 stages of prebiotic evolution - Answer 1. Geophysical - composition of Earth
and atmosphere
2. Chemical - building blocks of life being synthesized
3. Biological - building blocks organize into living cells
What is a protein - Answer -Made up of amino acids
-Has a complex tertiary structure
-Variable stability
-Has catalytic ability as an enzyme
What is DNA - Answer -Made up of four 2' deoxy nucleotides (A,T,C,G)
-Has a double helix conformation
-Very stable
-No catalytic ability (stores genomes)
What is RNA - Answer -Four nucleotides (A,U,G,C)
-Has a complex structure due to intramolecular hydrogen bonding)
-Less stable than DNA
