Module 2/ Microfilaments and intermediate filaments

Question 1

Microfilaments

Answer 1

Thin filament composed of actin proteins acting alone or with myosin to cause cell contraction

-Microfilaments form a network and can be branched

-Double chain of actin subunits

-Resist compression and maintains the shape of the cell

-Can interact with a protein myosin to cause muscle cells contraction

-The sliding of microfilaments onto each other is powered by the myosin.

Question 2

Intermediate filaments

Answer 2

Intermediate filaments are strong flexible filaments of intermediate size (between and microfilaments) that provide mechanical support of the cell against physical stress

-The intermediate filaments are only found in the cells of some animals, including vertebrates.

-Intermediate filaments are more permanent (not disassembled and reassembled as much as microtubules and microfilaments).

-Can bear tension (like microfilaments), maintain the shape of a cell and the nucleus (nuclear lamina) and fix the position of organelles.