Worksheets4.3-4.4 signal Transduction Pathways & Changes to STP's
Total questions: 50
Worksheet time: 28mins
Receptor proteins can be found in the
nucleus
cytosol
cell membrane
all of the above
Which molecule will most likely diffuse across plasma membrane?
glucose
carbon dioxide
sodium ion
DNA
In eukaryotic cells, which is a second messenger that is produced as a response to an external signal such as a hormone?
cyclic AMP
glycogen
glucose
epinephrine
The source of the phosphate for a phosphorylation cascade is...
cAMP
protein kinase
ATP
GTP
An example of LOCAL cell communication is:
White blood cells bumping into each other sharing antigen info
Neurons communicating across a synapse
Hormones traveling through the blood stream to target tissues
(2) examples of second messengers are...
Ca 2+
protein kinase
cAMP
G-protein coupled receptor
Select all that are true about cAMP.
it is used to activate protein kinases in the signal transduction pathway
it is broken down by phosphodiesterase
it is a g-protein coupled receptor
it is formed by adenylyl cyclase
Why do different target cells respond differently to the same signaling molecule (multiple choice).
There are different response molecules in the cell
There are different signal transduction pathways
There are different receptors in plasma membrane
What are the two types of hormones and where are their receptors typically located?
lipid soluble, binds to receptors in plasma membrane
lipid soluble, bind to receptors in cytoplasm or nucleus
water soluble, binds to receptors in plasma membrane
water soluble, bind to receptors in cytoplasm or nucleus
If phosphorylation (of ATP or GTP) did not occur, what would happen?
The ligand would bind, and the signaling pathway would proceed through transduction to cellular response.
The ligand would bind, but the signaling pathway would not proceed through the transduction step.
The ligand would bind and the signaling pathway would proceed through the transduction step, but would not produce a cellular response.
Choose all correct answer choices regarding the calcium ion.
Acts as a second messenger in the signal transduction pathway
Is found in low concentrations outside the cell
Is released from the mitochondria and endoplasmic reticulum when a cell signaling molecule binds to a cell-surface receptor
Is found in low concentrations in the cytoplasm
Which statement is false?
Cells are bombarded with numerous signals, but they respond to only a few.
A cell’s receptors determine whether or not the cell will respond to a signal.
Receptor proteins are very specific.
Protein kinase receptors are a type of cytoplasmic receptor.
A benefit of the many steps involved in a protein kinase cascade is that they allow for
activation or inhibition of many enzymes.
amplification of the signal.
distribution of the signal throughout the inside of the cell. d
variation in the response.
all the answer choices are correct
Epinephrine is a protein hormone found in many animals. Epinephrine stimulates a signaling pathway that results in the breakdown of glycogen to glucose in the liver cells. Which of the following describes the initial steps in the process whereby epinephrine stimulates glycogen breakdown?
Epinephrine binds to a cell-surface receptor; the activated receptor stimulates production of the second messenger, cAMP
Epinephrine binds to a cell-surface receptor; the activated receptor catalyzes the conversion of glycogen to glucose
Epinephrine diffuses through the plasma membrane; the hormone dimerizes in the cytosol
Epinephrine is taken into the cell by endocytosis; glycogen is converted to glucose in the endocytotic vesicle
Which of the following is correct about signal transduction pathways?
Signal transduction pathways are found only in the cells of the most complex animals
Signal transduction pathways have evolved recently along the development of enlarged brain size in mammals
In the signal transduction pathways, a single molecule can stimulate the release of thoundsands of molecules of product within a cell
Signal transduction pathways are unique in that receptors that stimulate the pathway are located only on the surface of a plasma membrane
In general, all cell signaling causes
increased expression of genes.
an influx of ions.
protein kinase activity.
a change in receptor conformation
A molecule that binds to the particular three-dimensional structure of another molecule’s receptor site is known as a(n)
responder.
receptor.
ligand
To respond to a signal, a cell must have a(n) molecule that can detect the signal.
receptor
ligand
responder
Describe the impact of a mutation in any domain of the protein components of the transduction signaling pathway.
receptor unable to bind to ligand
no changes in transduction due to initial signal transduction from ligand
alters response of the cell
amplification of signaling pathway to bind more ligands
If phosphorylation (of ATP or GTP) did not occur, what would happen?
The ligand would bind, and the signaling pathway would proceed through transduction to cellular response.
The ligand would bind, but the signaling pathway would not proceed through the transduction step.
The ligand would bind and the signaling pathway would proceed through the transduction step, but would not produce a cellular response.
Choose all correct answer choices regarding the calcium ion.
Acts as a second messenger in the signal transduction pathway
Is found in low concentrations outside the cell
Is released from the mitochondria and endoplasmic reticulum when a cell signaling molecule binds to a cell-surface receptor
Is found in low concentrations in the cytoplasm
Which of the following statements is correct?
Cells communicates with one another in multicellular organisms using extracellular signalling molecules or hormones.
Cells communicates with one another in unicellular organisms using extracellular signalling antigens and antibodies.
Cells communicates with one another in multicellular organisms using intracellular signalling molecules only.
Cells communicates with one another in unicellular organisms using intracellular signalling antigens and antibodies.
What could happen to target cells in an animal that lack receptor for local regulators?
They could compensate by receiving nutrients via an α factor.
They could develop normally in response to neurotransmitters instead.
They could divide but never reach full size.
They would not be able to multiply in response to growth factors from nearby cells.
This is an example of
paracrine signalling
endocrine signalling
autocrine signalling
juxtacrine signalling
This is an example of
paracrine signalling
endocrine signalling
autocrine signalling
juxtacrine signalling
This is an example of
paracrine signalling
endocrine signalling
autocrine signalling
juxtacrine signalling
Give the correct sequence of apoptosis:
- Nucleus begins to break
- Nucleus condensation and formation of bleb
- Phagocytosis of apoptotic bodies
1,2,3
2,3,1
3,2,1
2,1,3
Each of the following numbered processes are involved in signal transduction pathways:
i Response
ii Amplification
iii Reception
iv Transduction
Which of the following represents the sequence of events in a typical signal transduction pathway?
i, ii, iii, iv
iii, i, iv, ii
ii, iv, i, iii
iii, iv, ii, i
Which step would be the final step in a signal transduction pathway?
phophorylation of proteins
activation of protein
change in gene expression
binding a ligand to a receptor
What is the role of protein kinase in a signal transduction pathway?
activates a molecule by adding a phosphate to the target molecule
deactivate a molecule by removing a phosphate from the target molecule
activates a molecule by removing a phosphate from the target molecule
deactivate a molecule by adding a phosphate to the target molecule
All mammals have a similar signaling pathway for the uptake of glucose by cells from the blood. What does this suggest about the evolutionary relatedness
Species that use the same signal pathway are probably closely related by evolution.
Species that use the same signal pathway are probably not closely related by evolution
Species that use the same signal pathway will look the same anatomically
Species that use the same signal pathway would not be in the same kingdom.
What class of enzymes removes phosphate from proteins to deactivate them?
catalases
phosphatases
kinases
amplifases
What action describes a response to internal stimuli?
Catching a ball at a baseball game
Drinking when you are thirsty
Running at the sight of a wild lion
Writing a thank you note
When a molecule can occupy the same active site as the substrate, a situation called __________________ can result
Competitive lnhibition
Allosteric Regulation
Non-Competitive Inhibition
Feedback Inhibition
“They are cells specialized in picking up stimulus, whether they are internal or external, and send them to the brain through the nervous system”. This is the definition of...
Stimulus
Receptor
Sense
Taste
Why might you feel something touching you on your head quicker than on your foot.
The message from the head travels farther to the brain
the message from the foot travels farther to the brain
The head is less sensitive than the foot
The foot doesn't send messages to the brain
_______ plays a key role in Reward Pathways and is implicated in addictive disorders
Acetylcholine
Serotonin
Dopamine
GABA
What is the hormone that allows us to feel bliss, pleasure, euphoria and motivation.
Oxytocin
Dopamine
Endorphins
Serotonin
