Cunningham - Tumor Physiology lecture Flashcards
________ carries the genetic code (codons complementary to that of DNA genes) from the nucleus to the cytoplasm for controlling the type of protein formed.
A. Precursor messenger RNA B. Small nuclear RNA C. Messenger RNA D. Transfer RNA E. Ribosomal RNA
C. Messenger RNA
Which of the following is found in higher concentrations inside the cell versus in the extracellular fluid? A. Glucose B. Mg C. Ca D. HCO3
B. Mg
PIP2 is hydrolyzed into 2 second messengers by phospholipase C. Which of these second messengers then mobilizes intracellular Ca2+? A. DAG B. IP3 C. cAMP D. cGMP E. Calmodulin
Correct answer: B.
Ref: Cunningham, pg. 29
In the MAP Kinase pathway, Ras in its GTP-bound form sends a stimulatory signal to \_\_\_, which is a MAP kinase, kinase, kinase. A. Raf B. Mek C. Erk D. Fak E. Src
Correct answer: A.
Ref: Cunningham, p 41-42
Which of the following plays the most significant regulatory role in the restriction point decision of the cell cycle?
a) Cyclin A or B
b) Cyclin dependent kinase 2
c) P53
d) Retinoblastoma
Correct Answer: D
Ref: Cunningham, p 44
Explanation: CDK4/6 and cyclin D phosphorylates RB which releases it from the E2F transcription factor
What is the role of Bcl-2 in the cell?
a) Inhibits Bax in the intrinsic apoptosis pathway
b) Inhibits p53 in the extrinsic apoptosis pathway
c) Activates caspases in the extrinsic apoptosis pathway
d) Activates RB in the intrinsic pathway
Correct Answer: A
Ref: Cunningham, p 47
Explanation: p53 signals cell stress and activates the intrinsic pathway. Bcl-2 is not involved in the extrinsic pathway. RB is not involved in apoptosis.
Which cellular receptor does not utilize a second messenger?
A. G Protein Coupled Receptors
B. Tyrosine Kinase Receptors
C. All cellular receptor families utilize second messenger systems
D. Nuclear receptors
Correct answer: B
Ref: Cunningham p 23, 31, 39
What is the function of Calmodulin?
A. Facilitates release of Ca2+ from the sarcoplasmic reticulum
B. Binds Ca2+ in the cytosol
C. Serves as a second messenger for the GPCR
D. Serves as a second messenger for the Tyrosine Kinase Receptor
Correct answer: B
Ref: Cunningham p 25
Which one of the following enzymes hydrolyzes 3’,5’-adenosine monophosphate (cAMP) to 5’AMP?
a. Phosphodiesterase
b. Protein kinase A
c. Adenylyl cyclase
d. Myosin kinase
Correct answer: A
Ref: Cunningham p 27
Phosphatidylinositol 4,5-bisphosphate (PIP2) is hydrolyzed to which combination of the following second messengers?
a. Calcium and 3’,5’-adenosine monophosphate (cAMP)
b. Diacylglycerol (DAG) and inositol 1,4,5-triphosphate (IP3)
c. Inositol 1,4,5-triphosphate (IP3) and calcium
d. Diacylglycerol (DAG) and 3’,5’-adenosine monophosphate (cAMP)
Correct answer: B
Ref: Cunningham p 24
Which ion is an essential component of the DNA-binding domain of nuclear receptors?
a. magnesium
b. zinc
c. copper
d. iron
Answer: B
Reference: Cunningham, p 30
Phosphorylation reactions in cell receptors of cell growth pathways primarily involve which amino acid residue?
a. threonine
b. serine
c. cysteine
d. tyrosine
Answer: D
Reference: Cunningham, p. 39
Which 3 kinases are mitogen activated protein kinases or MAP kinases? A. Raf, Mek and Erk B. GDP, Mek and Erk C. Ras, Raf and Erk D. p53, Ras Raf
Correct Answer: A
Ref: Cunningham p. 41
What phase of the cell cycle is driven by Cyclin D/CDK4, 6? A. M B. S C. G1 D. G0
Correct answer: C
Ref. Cunningham p 38
What protein binds cytoplasmic Ca2+ to activate cellular processes?
a. Cyclic AMP
b. Phosphatidylinositol
c. Calmodulin
d. Cyclin
Correct answer: C
Ref: Cunningham 25