Cell biology - The Cell ; Cytoskeleton and cillia Flashcards
defects in keratin and collagen cause which of these conditions ?
a. progeria
b. epidermolysis bullosa
b.epidermolysis bullosa
defects in nuclear lamin cause which of these conditions ?
a. progeria
b. epidermolysis bullosa
a.progeria
what are the 3 types of cytoskeletal filament
intermediate
microtubules
actin microfilaments
what type of filaments provide tensile strength and are made up mostly of keratin, vimentin and lamin?
a. intermediate
b. microtubules
c. actin microfilaments
a. intermediate
the size of intermediate filaments lies between..
a. actin and myosin
b. microtubules and myosin
c. microtubules and actin
a.actin and myosin
which filaments have a key role in tethering cells to other cells eg epithelium?
a. intermediate
b. microtubules
c. actin microfilaments
a. intermediate
how do intermediate filaments strengthen epithelial cell contacts?
a. tight junctions
b. loose junctions
c. desmosomes
c.desmosomes
allow sheet formation and spread of mechanical stretch
what is the second stage of IF formation/
a. monomers bind to form dimers
b. dimers bind to form staggered tetramers
c. tetramers can pack together end to end
d. IF tetramers pack together and form a helical array of 8 fibres in a ropelike formation
a.monomers bind to form dimers
what type of IF is present in epithelia?
a. keratins
b. vimentin
c. neurofilaments
d. lamins
a.keratins
what type of IF is present in CT?
a. keratins
b. vimentin
c. neurofilaments
d. lamins
b.vimentin
what type of IF is present in nerve cells?
a. keratins
b. vimentin
c. neurofilaments
d. lamins
c.neurofilaments
what type of IF is present in nucleus?
a. keratins
b. vimentin
c. neurofilaments
d. lamins
d.lamins
what filaments are affected in EB
a. intermediate
b. microtubules
c. actin microfilaments
a.intermediate
an autoimmunecondition in which the bodies antibodies attack the desmosomes is known as..
a,EB
b. progeria
c. pemphigus
c.pemphigus
in pemphigus what do the bodys antibodies attack
a. keratin
b. nuclear lamina
c. desmosomes
c.desmosomes
IFs on the nuclear lamina line which face of the nuclear envelope to provide attachment sites for DNA binding chromatin
a. outer
b. inner
b.inner
what is the disassembly and reform of the nuclear lamina controlled by
a. ATP
b. phosphorylation of keratin
c. phosphorylation of lamins
c.phosphorylation of lamins
when the lamina is phosphorylated it is…
a. assembled
b. disassembled
b.disassembled
eg dividing cells
a mutation in nuclear lamina A leads to which condition
a,progeria
b. pemphigus
c. epidermolysis bullosa
a,progeria
unstable nuclear envelope lower capacity for tissue repair
what protein are the stiff hollow tubes known as microtubules made up of
a. keratin
b. lamins
c. tubulin
c.tubulin
where are microtubules anchored
a. centriole
b. centrosome
c. histones
b.centrosome
what filaments are involved in cell division, anchoring organelles and intracellular transport
a. intermediate
b. microtubules
c. actin microfilaments
b.microtubules
how many polar protofilaments made up of tubulin dimers combine to make up a microtubule with a positive and negative end
a,8
b. 12
c. 10
d. 13
d.13
which of these filaments grow from an organising centre in the cell
a. intermediate
b. microtubules
b.microtubules
y tubulin rings serve as a nucleation site for the growth of the centrosome .which end of the tubule embeds in the centrosome
a. negative
b. positive
a.negative
growth occurs outwards from plus end
which filaments grow and shrink independently (dynamic instability)
a. intermediate
b. microtubules
c. actin microfilaments
b.microtubules
what type of proteins are tubulin
a. G proteins
b. enzymes
c. hormones
a.G proteins
tubulin GTP forms which microtubule
a. growing
b. shrinking
a.growing
what happens to the microtubule when GTP is hydrolysed on the tubulin
a. grows
b. shrinks
b.shrinks
only GTP on which tubulin subunit is available for hydrolysis
a. beta
b. alpha
a. beta
capping proteins at which end of the microtubule stabilise it, leading to polarisation of the cell
a. negative
b. positive
b.positive
all transport occurs where in relation to the microtubule in neurons
a,inside
b.outside
b.outside
what type of filaments make up cillia and flagella
a. intermediate
b. microtubules
c. actin microfilaments
b.microtubules
the 9+2 model applies to which filament
a. intermediate
b. microtubules
c. actin microfilaments
b.microtubules
in cillia, 9 doublet microtubules around central pair
what motor protein is involved in the bending of cillia
ciliary dynein
what condition is autosomal recessive and leads to infertile males and increased bronchial infections
a. pemphigus
b. EB
c. progeria
d. Kartageners syndrome
d.Kartageners syndrome
what filaments are targetted by cancer drugs
a. intermediate
b. microtubules
c. actin microfilaments
b.microtubules
which of these drugs blocks cell division by inhibiting microtubule assembly
a. vincristine
b. paclitaxel
a. vincristine
which of these drugs blocks cell division by preventing microtubule shrinking
a. vincristine
b. paclitaxel
b.paclitaxel
which fibres are involved in cell movement and shape
a. intermediate
b. microtubules
c. actin microfilaments
c.actin microfilaments
true or false actin filaments are polarised, unstable and can be stabilised by actin binding proteins
a. true
b. false
a.true
which filaments make up the cillia
a. intermediate
b. microtubules
c. actin microfilaments
c.actin microfilaments
which filament is made up of a 2 stranded helix twist repeating every 37nm
a. intermediate
b. microtubules
c. actin microfilaments
c.actin microfilaments
actin chains grow by addition of an actin monomer carrying what
a. GTP
b. ATP
c. ADP
d. pi
b. ATP
hydrolysing it to adp
adp remains trapped until actin monomer dissociates
polymerisation of what causes the leading end of a cell to push the cell forward
a. intermediate
b. microtubules
c. actin microfilaments
d. myosin
c.actin microfilaments
forms a new actin cortex
contraction by myosin 2 at which end of the cell draws the cell forward in cell crawling
a. moving end
b. anchored end
b.anchored end
integrins are molecular hooks that allow cells to attach. what process are they involved in
a. cell crawling
b. microtubule building
c. desmosome formation
a.cell crawling
where is most of the actin found in the cell
a,surrounding the nuclear envelope
b. concentrated under the cell membrane
b. concentrated under the cell membrane
what proteins form the cell cortex meshwork cross linking to proteins eg spectrin and ankyrin
