Essential Cell Biology, 5th Edition, by Bruce
Alberts, Exam 4 Latest Update With Multiple,
Correctly Answered Questions |Single &
Multiple choice and essays|
What organelles are part of the endomembrane system? ✔- Golgi,
ER, lysosomes, endosomes, chloroplasts, peroxisomes
T/F: Mitochondria is part of the endomembrane system ✔- False.
Where are proteins in chloroplast synthesized? ✔- Cytosol and
chloroplast
What transports the components of the endomembrane system ✔-
Vesicles
*What percent of a eukaryotic cell is comprised of cytosol? ✔-
50%, half
Muscular dystrophy ✔- nuclear lamin
Intermediate filaments #7 on Review 17 ✔- Mutation in their
keratin. through Desmosomes. Vimentin
Where are organelle proteins made ✔- Cytosol
,What guides proteins to the correct organelle? ✔- Signal sequences
What proteins do not have signal sequences? ✔- Proteins that
function in the cytosol
Proteins translated in cytosol and lack sorting signal go where? ✔-
Cytosol
Signal sequences that direct proteins to correct compartment are
✔- Encoded in the amino acid
Where does photosynthesis occur? ✔- Chloroplast
**Where does transcription occur? ✔- Inside the nucleus
**Where does oxidative phosphorylation occur? ✔- Inner
mitochondrial membrane
**Where does the modification of secreted proteins occur? ✔-
Golgi and rough ER
**Where does steroid hormone synthesis occur? ✔- Smooth ER
Hormones cross the membrane and bind ✔- Nuclear receptors.
Steroid and thyroid hormones. Hydrophobic molecules
Nitric oxide ✔- Triggers smooth muscle relaxation in blood vessel.
Rapid diffusion across plasma membrane
**Hormones stimulate what ✔- membrane bound G protein.
stimulate adenylate cyclase to produce cAMP
,**Where does degradation of organelles occur? ✔- lysosome
**Where is new membrane synthesized? ✔- New membrane lipids
are synthesized on the smooth ER and inserted into the smooth ER
membrane.
**Where does the breakdown of lipids and toxic molecules happen?
✔- Peroxisome
**GAP ✔- turns switch protein off by promoting GTP hydrolysis
What determines whether a cell will respond to a signaling molecule?
✔- Presence of receptors inside or outside the cell
What is the best signal to send a signal to most cells? ✔- Hormone.
Endocrine signal ✔- Hormone signal. Similar to broadcast on radio.
Long range
Paracrine/ Autofind signal ✔- Nearby cells. Similar to posting a flyer
on a board in a neighborhood
Neuronal signalling ✔- Neurotransmitter delivered @ synapse.
Similar to a phone call/text/email
Direct contact signaling ✔- Cells are in physical contact. Similar to
face to face conversation
What signaling travels the largest distance? ✔- Endocrine
, What type of signaling is local and secretes to neighboring cells? ✔-
Paracrine
Where would a hydrophilic molecule interact with a receptor? ✔-
On the cell surface
Where would you expect a steroid to interact with a receptor? ✔-
Inside the nucleus of the cell
Foreign substances (methanol, morphine) exert initial effects by ✔-
interacting with cell-surface receptors and causing signal to be
inappropriately transduced in absence of normal stimulus.
****How many transmembrane domains do GPCRs have ✔- 7.
GPCRs membrane domains are pharmacologically important (****1/3
drugs today use GPCR)
**Why are GPCRs important ✔- 1/3 of all drugs today work
through GPCR. Also allows for amplification like rods in vision
***2 main types of GTP binding proteins ✔- Large trimeric GTP
proteins and momomeric GTP binding proteins
What type of protein is GPCRs best friend* ✔- Trimeric GTP binding
protein. G proteins.
What contains nuclear localization signals (NLS) that direct transport
✔- Folded nuclear proteins
What is role of nuclear localization ✔- import receptors and cargo
across nuclear envelope. bound by cytoplasmic proteins
Alberts, Exam 4 Latest Update With Multiple,
Correctly Answered Questions |Single &
Multiple choice and essays|
What organelles are part of the endomembrane system? ✔- Golgi,
ER, lysosomes, endosomes, chloroplasts, peroxisomes
T/F: Mitochondria is part of the endomembrane system ✔- False.
Where are proteins in chloroplast synthesized? ✔- Cytosol and
chloroplast
What transports the components of the endomembrane system ✔-
Vesicles
*What percent of a eukaryotic cell is comprised of cytosol? ✔-
50%, half
Muscular dystrophy ✔- nuclear lamin
Intermediate filaments #7 on Review 17 ✔- Mutation in their
keratin. through Desmosomes. Vimentin
Where are organelle proteins made ✔- Cytosol
,What guides proteins to the correct organelle? ✔- Signal sequences
What proteins do not have signal sequences? ✔- Proteins that
function in the cytosol
Proteins translated in cytosol and lack sorting signal go where? ✔-
Cytosol
Signal sequences that direct proteins to correct compartment are
✔- Encoded in the amino acid
Where does photosynthesis occur? ✔- Chloroplast
**Where does transcription occur? ✔- Inside the nucleus
**Where does oxidative phosphorylation occur? ✔- Inner
mitochondrial membrane
**Where does the modification of secreted proteins occur? ✔-
Golgi and rough ER
**Where does steroid hormone synthesis occur? ✔- Smooth ER
Hormones cross the membrane and bind ✔- Nuclear receptors.
Steroid and thyroid hormones. Hydrophobic molecules
Nitric oxide ✔- Triggers smooth muscle relaxation in blood vessel.
Rapid diffusion across plasma membrane
**Hormones stimulate what ✔- membrane bound G protein.
stimulate adenylate cyclase to produce cAMP
,**Where does degradation of organelles occur? ✔- lysosome
**Where is new membrane synthesized? ✔- New membrane lipids
are synthesized on the smooth ER and inserted into the smooth ER
membrane.
**Where does the breakdown of lipids and toxic molecules happen?
✔- Peroxisome
**GAP ✔- turns switch protein off by promoting GTP hydrolysis
What determines whether a cell will respond to a signaling molecule?
✔- Presence of receptors inside or outside the cell
What is the best signal to send a signal to most cells? ✔- Hormone.
Endocrine signal ✔- Hormone signal. Similar to broadcast on radio.
Long range
Paracrine/ Autofind signal ✔- Nearby cells. Similar to posting a flyer
on a board in a neighborhood
Neuronal signalling ✔- Neurotransmitter delivered @ synapse.
Similar to a phone call/text/email
Direct contact signaling ✔- Cells are in physical contact. Similar to
face to face conversation
What signaling travels the largest distance? ✔- Endocrine
, What type of signaling is local and secretes to neighboring cells? ✔-
Paracrine
Where would a hydrophilic molecule interact with a receptor? ✔-
On the cell surface
Where would you expect a steroid to interact with a receptor? ✔-
Inside the nucleus of the cell
Foreign substances (methanol, morphine) exert initial effects by ✔-
interacting with cell-surface receptors and causing signal to be
inappropriately transduced in absence of normal stimulus.
****How many transmembrane domains do GPCRs have ✔- 7.
GPCRs membrane domains are pharmacologically important (****1/3
drugs today use GPCR)
**Why are GPCRs important ✔- 1/3 of all drugs today work
through GPCR. Also allows for amplification like rods in vision
***2 main types of GTP binding proteins ✔- Large trimeric GTP
proteins and momomeric GTP binding proteins
What type of protein is GPCRs best friend* ✔- Trimeric GTP binding
protein. G proteins.
What contains nuclear localization signals (NLS) that direct transport
✔- Folded nuclear proteins
What is role of nuclear localization ✔- import receptors and cargo
across nuclear envelope. bound by cytoplasmic proteins
