Which of the following is NOT a major class of cell signaling molecules?
a) Hormones
b) Neurotransmitters
c) Steroids
d) Ribosomes
Answer: d
Cell signaling is essential for:
a) Cell growth and division
b) Development and differentiation
c) Immune response
d) All of the above
Answer: d
The process by which cells communicate with each other is called:
a) Signal transduction
b) Cell signaling
c) Intercellular communication
d) Signal amplification
Answer: c
Which of the following is NOT a mechanism of cell signaling?
a) Autocrine signaling
b) Paracrine signaling
c) Endocrine signaling
d) Exocrine signaling
Answer: d
Receptors for lipid-soluble signaling molecules are typically located in the:
a) Plasma membrane
b) Cytoplasm
c) Nucleus
d) Mitochondria
Answer: c
Which of the following is an example of a direct cell-cell signaling mechanism?
a) Endocrine signaling
b) Paracrine signaling
c) Gap junctions
d) Synaptic signaling
Answer: c
The binding of a signaling molecule to its receptor triggers a series of events known as:
a) Signal amplification
b) Signal transduction
c) Signal termination
d) Signal integration
Answer: b
Which of the following is NOT a type of cell surface receptor?
a) G protein-coupled receptor (GPCR)
b) Receptor tyrosine kinase (RTK)
c) Ion channel receptor
d) Intracellular receptor
Answer: d
Second messengers are small molecules that:
a) Are released by cells to communicate with neighboring cells
b) Amplify the signal received by cell surface receptors
c) Bind directly to DNA to regulate gene expression
d) Are involved in cell adhesion and migration
Answer: b
Which of the following is NOT a second messenger?
a) cAMP (cyclic adenosine monophosphate)
b) IP3 (inositol trisphosphate)
c) cGMP (cyclic guanosine monophosphate)
d) mRNA (messenger RNA)
Answer: d
The process by which a cell responds to a signaling molecule by changing its gene expression is known as:
a) Signal transduction
b) Signal amplification
c) Signal termination
d) Signal integration
Answer: a
Which of the following is a downstream effect of cell signaling?
a) Alteration of enzyme activity
b) Changes in gene expression
c) Cytoskeletal rearrangements
d) All of the above
Answer: d
The binding of a signaling molecule to its receptor can activate which of the following signaling pathways?
a) Protein kinase cascade
b) Second messenger signaling
c) G protein signaling
d) All of the above
Answer: d
Protein phosphorylation is a common mechanism in cell signaling and is catalyzed by:
a) Protein kinases
b) Protein phosphatases
c) G proteins
d) Receptor tyrosine kinases
Answer: a
The process by which a signaling molecule is removed from the extracellular space to terminate signaling is called:
a) Signal transduction
b) Signal amplification
c) Signal termination
d) Signal integration
Answer: c
The cellular response to a signaling molecule can include:
a) Changes in gene expression
b) Alterations in enzyme activity
c) Cytoskeletal rearrangements
d) All of the above
Answer: d
Which of the following is an example of an intracellular signaling pathway?
a) G protein-coupled receptor (GPCR) signaling
b) Receptor tyrosine kinase (RTK) signaling
c) Ion channel signaling
d) Nuclear receptor signaling
Answer: d
The Ras/MAPK pathway is an example of a signaling pathway involved in:
a) Cell proliferation
b) Cell differentiation
c) Apoptosis
d) All of the above
Answer: d
G protein-coupled receptors (GPCRs) transmit signals by activating:
a) Second messengers
b) Protein kinases
c) G proteins
d) Receptor tyrosine kinases
Answer: c
The binding of a signaling molecule to a receptor tyrosine kinase (RTK) leads to:
a) Activation of downstream signaling pathways
b) Phosphorylation of tyrosine residues on the receptor
c) Recruitment of signaling proteins to the receptor
d) All of the above
Answer: d
The PI3K/Akt pathway is involved in regulating:
a) Cell survival and proliferation
b) Cell adhesion and migration
c) Apoptosis
d) All of the above
Answer: d
Which of the following is NOT a characteristic of cancer cells?
a) Increased cell proliferation
b) Loss of response to cell signaling
c) Disruption of cell adhesion
d) Reduced DNA repair capacity
Answer: b
The Wnt signaling pathway plays a critical role in:
a) Embryonic development
b) Tissue homeostasis
c) Stem cell maintenance
d) All of the above
Answer: d
The JAK/STAT pathway is involved in:
a) Immune response
b) Cell growth and differentiation
c) Inflammation
d) All of the above
Answer: d
Which of the following is an example of ligand-gated ion channel signaling?
a) Acetylcholine signaling at neuromuscular junctions
b) Insulin signaling in target cells
c) Epinephrine signaling in response to stress
d) Growth factor signaling in cell proliferation
Answer: a
The Hedgehog signaling pathway is involved in:
a) Embryonic development
b) Tissue regeneration
c) Cell fate determination
d) All of the above
Answer: d
Which of the following is NOT a component of the Notch signaling pathway?
a) Notch receptor
b) Delta ligand
c) G protein
d) CSL transcription factor
Answer: c
Calcium ions are important signaling molecules and can regulate:
a) Muscle contraction
b) Neuronal signaling
c) Enzyme activity
d) All of the above
Answer: d
Nitric oxide (NO) acts as a signaling molecule in various physiological processes, including:
a) Vasodilation
b) Neurotransmission
c) Immune response
d) All of the above
Answer: d
The cAMP/PKA pathway is involved in regulating:
a) Hormone production and secretion
b) Metabolism
c) Gene expression
d) All of the above
Answer: d
The Hedgehog signaling pathway is dysregulated in which type of cancer?
a) Skin cancer
b) Lung cancer
c) Breast cancer
d) Pancreatic cancer
Answer: a
Which of the following is NOT a component of the TGF-beta signaling pathway?
a) TGF-beta receptor
b) Smad proteins
c) G protein
d) TGF-beta ligand
Answer: c
The Jak-Stat pathway is activated by which class of cell signaling molecules?
a) Growth factors
b) Cytokines
c) Hormones
d) Neurotransmitters
Answer: b
Which of the following is NOT a function of the Wnt signaling pathway?
a) Cell proliferation
b) Cell differentiation
c) Cell migration
d) Apoptosis
Answer: d
The Notch signaling pathway is involved in:
a) Cell fate determination
b) Tissue regeneration
c) Immune response
d) All of the above
Answer: d
Which of the following is NOT a component of the MAPK signaling pathway?
a) MAPK kinase (MEK)
b) MAPK kinase kinase (MAP3K)
c) MAPK phosphatase (MKP)
d) MAPK inhibitor (MKI)
Answer: d
The Jak-Stat signaling pathway is dysregulated in which type of cancer?
a) Leukemia
b) Breast cancer
c) Colon cancer
d) Lung cancer
Answer: a
Which of the following is an example of a hormone involved in cell signaling?
a) Insulin
b) Serotonin
c) Epinephrine
d) All of the above
Answer: d
Which of the following is an example of autocrine signaling?
a) Nerve cell communication
b) Immune cell communication
c) Cancer cell growth
d) Hormone secretion
Answer: c
The PI3K/Akt pathway is dysregulated in which type of cancer?
a) Breast cancer
b) Prostate cancer
c) Pancreatic cancer
d) All of the above
Answer: d
Which of the following is NOT a component of the Hedgehog signaling pathway?
a) Sonic Hedgehog (Shh) ligand
b) Patched (Ptch) receptor
c) Smoothened (Smo) receptor
d) G protein
Answer: d
The Wnt signaling pathway is dysregulated in which type of cancer?
a) Colorectal cancer
b) Liver cancer
c) Brain cancer
d) All of the above
Answer: d
Which of the following is NOT a component of the cAMP/PKA signaling pathway?
a) Adenylyl cyclase
b) cAMP phosphodiesterase
c) Protein kinase A (PKA)
d) G protein
Answer: d
The PI3K/Akt pathway is activated by which class of cell signaling molecules?
a) Growth factors
b) Cytokines
c) Hormones
d) Neurotransmitters
Answer: a
The cGMP pathway is involved in regulating:
a) Smooth muscle relaxation
b) Cell proliferation
c) Gene expression
d) All of the above
Answer: d
The Wnt signaling pathway is activated by which class of cell signaling molecules?
a) Growth factors
b) Cytokines
c) Hormones
d) Wnt ligands
Answer: d
The Hippo signaling pathway is involved in regulating:
a) Cell growth and proliferation
b) Tissue regeneration
c) Organ size control
d) All of the above
Answer: d
Which of the following is NOT a component of the Hippo signaling pathway?
a) Yes-associated protein (YAP)
b) Transcriptional coactivator with PDZ-binding motif (TAZ)
c) Wnt ligand
d) Salvador/Warts/Hippo (SWH) kinase complex
Answer: c
The Hedgehog signaling pathway is activated by which class of cell signaling molecules?
a) Growth factors
b) Cytokines
c) Hormones
d) Hedgehog ligands
Answer: d
The Smad signaling pathway is involved in:
a) TGF-beta signaling
b) BMP signaling
c) Activin signaling
d) All of the above
Answer: d
Which of the following is NOT a component of the Smad signaling pathway?
a) TGF-beta receptor
b) Smad proteins
c) G protein
d) Smad-binding element (SBE)
Answer: c
The Notch signaling pathway is dysregulated in which type of cancer?
a) Breast cancer
b) Lung cancer
c) Leukemia
d) All of the above
Answer: d
Which of the following is an example of paracrine signaling?
a) Hormone secretion into the bloodstream
b) Nerve cell communication
c) Immune cell communication
d) Growth factor signaling in cell proliferation
Answer: d
The Jak-Stat signaling pathway is activated by which class of cell signaling molecules?
a) Growth factors
b) Cytokines
c) Hormones
d) Jak-Stat ligands
Answer: b
The Smad signaling pathway is dysregulated in which type of cancer?
a) Lung cancer
b) Colon cancer
c) Breast cancer
d) All of the above
Answer: d
The Notch signaling pathway is activated by which class of cell signaling molecules?
a) Growth factors
b) Cytokines
c) Hormones
d) Notch ligands
Answer: d
Which of the following is NOT a component of the PI3K/Akt signaling pathway?
a) Phosphatidylinositol 3-kinase (PI3K)
b) Akt (protein kinase B)
c) G protein
d) mTOR (mammalian target of rapamycin)
Answer: c
The Hippo signaling pathway is dysregulated in which type of cancer?
a) Liver cancer
b) Breast cancer
c) Pancreatic cancer
d) All of the above
Answer: d
Which of the following is NOT a component of the cGMP signaling pathway?
a) Guanylyl cyclase
b) cGMP phosphodiesterase
c) Protein kinase G (PKG)
d) G protein
Answer: d
The Hippo signaling pathway is activated by which class of cell signaling molecules?
a) Growth factors
b) Cytokines
c) Hormones
d) Hippo ligands
Answer: b
The Jak-Stat signaling pathway is involved in regulating:
a) Immune response
b) Cell growth and differentiation
c) Inflammation
d) All of the above
Answer: d
The Wnt signaling pathway is an example of a(n) __________ signaling pathway.
a) Canonical
b) Non-canonical
c) Autocrine
d) Paracrine
Answer: a
The Notch signaling pathway is activated by direct cell-cell interactions mediated by:
a) Ligand-receptor binding
b) G protein activation
c) Cytokine secretion
d) Membrane fusion
Answer: a
The cAMP/PKA signaling pathway is dysregulated in which type of cancer?
a) Breast cancer
b) Ovarian cancer
c) Pancreatic cancer
d) All of the above
Answer: d
The Hedgehog signaling pathway is involved in:
a) Cell proliferation
b) Cell differentiation
c) Tissue patterning
d) All of the above
Answer: d
The Smad signaling pathway is dysregulated in which type of cancer?
a) Breast cancer
b) Prostate cancer
c) Pancreatic cancer
d) All of the above
Answer: d
Which of the following is an example of endocrine signaling?
a) Hormone secretion into the bloodstream
b) Nerve cell communication
c) Immune cell communication
d) Growth factor signaling in cell proliferation
Answer: a
The PI3K/Akt pathway is involved in regulating:
a) Cell survival and proliferation
b) Cell adhesion and migration
c) Metabolism
d) All of the above
Answer: d
The cGMP pathway is dysregulated in which type of cancer?
a) Colorectal cancer
b) Lung cancer
c) Pancreatic cancer
d) All of the above
Answer: d
The Hippo signaling pathway is activated by direct cell-cell interactions mediated by:
a) Ligand-receptor binding
b) G protein activation
c) Cell polarity cues
d) Membrane fusion
Answer: c
