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2025 Exam Questions With Correct Answers
/ // // // // //
Why //is //myelin //important //in //the //nervous //system?
A. /
/It /
/allows /
/signals /
/to //travel //faster //along //axons //because //depolarization //occurs //only //at //myelinated //locations.
B. /
/It /
/allows /
/signals /
/to /
/travel /
/faster //along //axons //because //depolarization //occurs //only //at //nonmyelinated //locations.
C. //It //bundles //the //dendrites //of //adjacent //neurons //together.
D. /
/It /
/increases /
/capacitance /
/across //the //cell //membrane, //which //helps //electrical //signals //to //leave //the //axons.
E. /
/It /
/traps /
/neurotransmitters, /
/increasing //their //concentrations //in //the //synaptic //cleft. //- //verified //answer(s)-✔✔B
,Which /
/type //of //cytoskeletal //fiber //is //the //primary //building //block //of //eukaryotic //cilia //and //flagella?
A. //Actin //microfilaments.
B. //Intermediate //filaments.
C. //Keratin.
D. //Microtubules.
E. //RNA. //- //verified //answer(s)-✔✔D. //Microtubules.
Which /
/of /
/the /
/following //human //cell //types //contains //the //LEAST //amount //of //RNA //involved //in //splicing?
A. //Lymphocytes
B. //Lymphoblasts
C. //Erythrocytes
D. //Erythroblasts
E. //Hepatocytes //- //verified //answer(s)-✔✔C. //Erythrocytes
Antimicrobial /
/drugs, /
/also /
/known /
/as /
/antibiotics, /
/inhibit /
/the /
/growth /
,/of /
/bacteria /
/by /
/targeting /
/cellular /
/components /
/present /
/in /
/bacteria. /
/Which //of //the //following //cellular //components //is //NOT //a //valid //antimicrobial //drug //target?
A. //Centrosome.
B. //Ribosome.
C. //Cell //wall.
D. //RNA //polymerase.
E. //DNA //polymerase //- //verified //answer(s)-✔✔A. //Centrosome.
Which //of //the //following //statements //concerning //the //nature //of //post-
transcriptional //processing //of //mRNA //is //INCORRECT?
A. //The //presence //of //introns //is //a //derived //trait //of //eukaryotes.
B. /
/Mitochondrial //mRNA //lacks //a //5′ //cap //because //capping //is //a //strictly //intranuclear //process.
C. /
/Recognition /
/of /
/splice /
/sites /
/by /
/the /
/spliceosome /
/is /
, /based /
/on /
/the /
/physical //conformation //of //the //mRNA //strand, //not //on //any //specific //consensus //sequence.
D. //In //some //genes, //poly-
A/
/tails //can //generate //genetic //diversity //by //being //added //at //one //of //multiple //possible //sites //on
//the //mRNA //transcript.
E. //Both //5′ //caps //and //poly-
A/
/tails //inhibit //the //degradation //of //the //mRNA //molecule //in //the //cytosol. //- //verified //answer(s)-
✔✔C. /
/Recognition /
/of /
/splice /
/sites /
/by /
/the /
/spliceosome /
/is /
/based /
/on /
/the /
/physical //conformation //of //the //mRNA //strand, //not //on //any //specific //consensus //sequence.
Cellular /
/metabolism /
/is /
/bidirectional /
/and /
/complex. /
/Indicate /
/whether /
/the /
/following /
Open
/ /
Exam
/ /
2025 Exam Questions With Correct Answers
/ // // // // //
Why //is //myelin //important //in //the //nervous //system?
A. /
/It /
/allows /
/signals /
/to //travel //faster //along //axons //because //depolarization //occurs //only //at //myelinated //locations.
B. /
/It /
/allows /
/signals /
/to /
/travel /
/faster //along //axons //because //depolarization //occurs //only //at //nonmyelinated //locations.
C. //It //bundles //the //dendrites //of //adjacent //neurons //together.
D. /
/It /
/increases /
/capacitance /
/across //the //cell //membrane, //which //helps //electrical //signals //to //leave //the //axons.
E. /
/It /
/traps /
/neurotransmitters, /
/increasing //their //concentrations //in //the //synaptic //cleft. //- //verified //answer(s)-✔✔B
,Which /
/type //of //cytoskeletal //fiber //is //the //primary //building //block //of //eukaryotic //cilia //and //flagella?
A. //Actin //microfilaments.
B. //Intermediate //filaments.
C. //Keratin.
D. //Microtubules.
E. //RNA. //- //verified //answer(s)-✔✔D. //Microtubules.
Which /
/of /
/the /
/following //human //cell //types //contains //the //LEAST //amount //of //RNA //involved //in //splicing?
A. //Lymphocytes
B. //Lymphoblasts
C. //Erythrocytes
D. //Erythroblasts
E. //Hepatocytes //- //verified //answer(s)-✔✔C. //Erythrocytes
Antimicrobial /
/drugs, /
/also /
/known /
/as /
/antibiotics, /
/inhibit /
/the /
/growth /
,/of /
/bacteria /
/by /
/targeting /
/cellular /
/components /
/present /
/in /
/bacteria. /
/Which //of //the //following //cellular //components //is //NOT //a //valid //antimicrobial //drug //target?
A. //Centrosome.
B. //Ribosome.
C. //Cell //wall.
D. //RNA //polymerase.
E. //DNA //polymerase //- //verified //answer(s)-✔✔A. //Centrosome.
Which //of //the //following //statements //concerning //the //nature //of //post-
transcriptional //processing //of //mRNA //is //INCORRECT?
A. //The //presence //of //introns //is //a //derived //trait //of //eukaryotes.
B. /
/Mitochondrial //mRNA //lacks //a //5′ //cap //because //capping //is //a //strictly //intranuclear //process.
C. /
/Recognition /
/of /
/splice /
/sites /
/by /
/the /
/spliceosome /
/is /
, /based /
/on /
/the /
/physical //conformation //of //the //mRNA //strand, //not //on //any //specific //consensus //sequence.
D. //In //some //genes, //poly-
A/
/tails //can //generate //genetic //diversity //by //being //added //at //one //of //multiple //possible //sites //on
//the //mRNA //transcript.
E. //Both //5′ //caps //and //poly-
A/
/tails //inhibit //the //degradation //of //the //mRNA //molecule //in //the //cytosol. //- //verified //answer(s)-
✔✔C. /
/Recognition /
/of /
/splice /
/sites /
/by /
/the /
/spliceosome /
/is /
/based /
/on /
/the /
/physical //conformation //of //the //mRNA //strand, //not //on //any //specific //consensus //sequence.
Cellular /
/metabolism /
/is /
/bidirectional /
/and /
/complex. /
/Indicate /
/whether /
/the /
/following /
