VERIFIED
MCB 150 FINAL EXAM WITH 100%
CORRECT ANSWERS 2023
Structure of Microtubules - Correct Answer-rigid, hollow tubes made of tubulin
What is tubulin - Correct Answer-a dimer of alpha-tubulin (GTP) and beta-tubulin (GDP)
How do tubulin dimers form MTS? - Correct Answer-they polymerize, assemble mt head
to tail so mt has polarity
Which end do polymerization and depolymerization happen on MT? - Correct Answer-
possible at both ends, but usually occurs at plus end bc minus end is anchored into
centrosome
What happens once there is a dimer addition to a microtubule? - Correct Answer-GTP
in b-tubulin is hydrolyzed and turned into GDP, GTP in a-tubulin is not hydrolyzed for
stability
Dynamic instability and GTP cap - Correct Answer-GTP bound tubulin prevents
subunits from peeling away so if polymerization slows down GTP cap is hydrolyzed and
microtubule starts depolymerizing
Tubulin + GTP - Correct Answer-= polymerization
Tubulin + no GTP - Correct Answer-= depolymerization
Does GTP bound tubulin have high or low affinity for tubulin? - Correct Answer-high
Does GDP bound tubulin have high or low affinity for tubulin? - Correct Answer-low
Colchicine and Colcemid affect on microtubules - Correct Answer-Binds tubulin-
>induces depolymerization->non-specifically affects all microtubules
Vincristine and vinblastine affect on microtubules - Correct Answer-Binds tubulin-
>induces depolymerization->targets rapidly dividing cells
Taxol affect on microtubules - Correct Answer-binds microtubules->stabilizes
microtubules->targets rapidly dividing cells
Function of microtubules - Correct Answer-interphase cell (guiding intracellular
transport), dividing cell (segregating chromosomes during mitosis), ciliated cell
(propulsion or sweeping of fluids over membranes)
, Where do new microtubules come from? - Correct Answer-mts originate from the
microtubule organizing center (MTOC)
What is major MTOC in animal cells? - Correct Answer-centrosome (origin and anchor)
What does centrosome contain? - Correct Answer-pair of centrioles, pericentriolar
material
Centrioles - Correct Answer-9 triplet arrangement of microtubules
Pericentriolar material - Correct Answer-amorphous collection of protein from which mts
emanate from
Where do new mts emanate from? - Correct Answer-gamma tubulin
Microtubules associated motor proteins - Correct Answer-kinesin moves toward plus
end, dynein moves toward negative end
Examples of stable microtubules providing polarity to a cell type - Correct Answer-
Neuron- extremely polarized (one side looks way different than the other), MTS in nerve
cells are not oriented the same way
Functions of microtubules AND their associated motor protein - Correct Answer-
intracellular vesicle transport, organelle movement and positioning, color changes,
bending of cilia and flagella, seperation of sister chromatids/ centrosomes during m
phase
Cilia vs. flagella - Correct Answer-cilia are shorter and flagella are longer, flagella whip
Axoneme - Correct Answer-"9+2" arrangement
Basal body - Correct Answer-minus ends of axoneme MTS are anchored into a basal
body, structurally similar to a centriole
Cilium/flagellum movement using axonemal dyneins - Correct Answer-dynein arms walk
along mts doublets on one side of axoneme, ATP causes dynein to walk toward minus
end and pull toward plus end
Cell theory - Correct Answer--cell is fundamental unit of life
-all living organisms are made of one or more cells
-all cells come from pre existing cells
Flemming 1882 - Correct Answer-introduced term mitosis
van Beneden 1883 - Correct Answer-reported a total number or threads in a cell
remains constant during subsequent divisions
MCB 150 FINAL EXAM WITH 100%
CORRECT ANSWERS 2023
Structure of Microtubules - Correct Answer-rigid, hollow tubes made of tubulin
What is tubulin - Correct Answer-a dimer of alpha-tubulin (GTP) and beta-tubulin (GDP)
How do tubulin dimers form MTS? - Correct Answer-they polymerize, assemble mt head
to tail so mt has polarity
Which end do polymerization and depolymerization happen on MT? - Correct Answer-
possible at both ends, but usually occurs at plus end bc minus end is anchored into
centrosome
What happens once there is a dimer addition to a microtubule? - Correct Answer-GTP
in b-tubulin is hydrolyzed and turned into GDP, GTP in a-tubulin is not hydrolyzed for
stability
Dynamic instability and GTP cap - Correct Answer-GTP bound tubulin prevents
subunits from peeling away so if polymerization slows down GTP cap is hydrolyzed and
microtubule starts depolymerizing
Tubulin + GTP - Correct Answer-= polymerization
Tubulin + no GTP - Correct Answer-= depolymerization
Does GTP bound tubulin have high or low affinity for tubulin? - Correct Answer-high
Does GDP bound tubulin have high or low affinity for tubulin? - Correct Answer-low
Colchicine and Colcemid affect on microtubules - Correct Answer-Binds tubulin-
>induces depolymerization->non-specifically affects all microtubules
Vincristine and vinblastine affect on microtubules - Correct Answer-Binds tubulin-
>induces depolymerization->targets rapidly dividing cells
Taxol affect on microtubules - Correct Answer-binds microtubules->stabilizes
microtubules->targets rapidly dividing cells
Function of microtubules - Correct Answer-interphase cell (guiding intracellular
transport), dividing cell (segregating chromosomes during mitosis), ciliated cell
(propulsion or sweeping of fluids over membranes)
, Where do new microtubules come from? - Correct Answer-mts originate from the
microtubule organizing center (MTOC)
What is major MTOC in animal cells? - Correct Answer-centrosome (origin and anchor)
What does centrosome contain? - Correct Answer-pair of centrioles, pericentriolar
material
Centrioles - Correct Answer-9 triplet arrangement of microtubules
Pericentriolar material - Correct Answer-amorphous collection of protein from which mts
emanate from
Where do new mts emanate from? - Correct Answer-gamma tubulin
Microtubules associated motor proteins - Correct Answer-kinesin moves toward plus
end, dynein moves toward negative end
Examples of stable microtubules providing polarity to a cell type - Correct Answer-
Neuron- extremely polarized (one side looks way different than the other), MTS in nerve
cells are not oriented the same way
Functions of microtubules AND their associated motor protein - Correct Answer-
intracellular vesicle transport, organelle movement and positioning, color changes,
bending of cilia and flagella, seperation of sister chromatids/ centrosomes during m
phase
Cilia vs. flagella - Correct Answer-cilia are shorter and flagella are longer, flagella whip
Axoneme - Correct Answer-"9+2" arrangement
Basal body - Correct Answer-minus ends of axoneme MTS are anchored into a basal
body, structurally similar to a centriole
Cilium/flagellum movement using axonemal dyneins - Correct Answer-dynein arms walk
along mts doublets on one side of axoneme, ATP causes dynein to walk toward minus
end and pull toward plus end
Cell theory - Correct Answer--cell is fundamental unit of life
-all living organisms are made of one or more cells
-all cells come from pre existing cells
Flemming 1882 - Correct Answer-introduced term mitosis
van Beneden 1883 - Correct Answer-reported a total number or threads in a cell
remains constant during subsequent divisions
