cytoskeleton Flashcards
What is the cytoskeleton?
microtubules + filaments
helps cells maintain shape and organisation
provides mechanical support
What are the 3 protein polymers
actin (microfilaments)
intermediate filaments
microtubules
The actin filament is a ……… ……… …………
The asymmetric shape of an actin monomer gives ….. to the ……
polarised double helix
polarity
filament
Actin filament requires ….. to be bound to the actin ……
Once incorporated into the filament, the …… is hydrolysed to …..
ATP
monomer
ATP
ADP
3 major functions of actin and example
- mechanical support e.g stereo cilia of cochlea bend
- changing/maintaining shape e.g biconcave RBC
- cell motility e.g muscle cells use to contract
Cytoplasmic intermediate filaments form a ………. typically most dense around the ……. and extending into the periphery. Functions are mainly ……..
network
nucleus
mechanical
Microtubules: There are .. polymer rods seen in a cross section of a microtuble
13
Microtubule: ….. one side and ….. the other, means that one end of polymer rod ends with ….. (+) subunit and other with a ….. (-). GTP being converted to ……
alpha beta alpha beta GDP
Microtubules are highly ……..
dynamic
Intermediate filaments form a …… around the ……. to anchor its position
meshwork
nucleus
Filopodia extend from the cell and are full of ……. …….
polymerising actin
Actin filaments bundles provide ………..
e.g. ………. to detect ………
support
stereo cilia
vibration
Microtubules stabilise …….. axons and involved ………. as the brain develops
mature
growth
Intermediate filaments stabilise ……. …….. ……… such as axons of …….. ………
long cell processes
nerve cells
The actin filaments are pulled upon by …… to drag the cell ……… The ……… used in a non muscle is a ……… which is a class of ……… proteins
Myosin forward myosin myosin-2 motor
