Cytoskeleton Key terms and questions

Cytoskeleton

Network of protein fibers with several functions

HW: Microfilaments/actin

Muscle contraction and cell movement. Time and stabile cell shape, made from actin monomers, smallest component of cytoskeleton

Actin

monomers that are part of microfilaments

Intermediate filament

Provide mechanical strength and structural support (resist tension, anchor the nucleus)

HW: Microtubules

Move organelles with the cell (via motor proteins) and also form rigid internal skelton for some cells, separates chomores during cell division, made of tubulin dimers

HW: Which is the correct order of cytoskeleton fibers from smallest -> largest?

Actin —> intermediate filaments —> microtubules

HW: Match the cell junction with the correct description:

Adhesion/anchoring junction

Attach cells strongly

HW: Match the cell junction with the correct description:

Tight junction

Form impermeable barriers

HW: Match the cell junction with the correct description:

Gap junction

Join plasma membrane for communication in animals

HW: Match the cell junction with the correct description:

Plasmodesmata

Join plasma membrane for communication in plants

Plasmodesmata

channels that pass between cell walls in plants to connect cytoplasm and allow materials to move from cell to cell (JOIN PLASMA MEMBRANE FOR COMMUNICATION IN PLANTS)

tight junctions

watertight seals between animal cells that prevent materials from leaking between cells (IMPERMEABLE BARRIERS)

Desmosomes

short proteins in the plasma membrane that act as spot wels, and join adjacent cells in tissues that stretch (Ex. heart, lungs, muscles) These are only present in animals.

Gap junctions

Protein lined pores that allow water and small molecules to pass (COMMMUNICATE) between adjacent ANIMAL cells, resemble plasmodesmata in plants.

QUIZ: What is the primary role of microtubules in the cytoskeleton

Form tracks for vesicle and organelle movement

Which of the following is NOT a component of the cytoskeleton

Ribosomes

HW: Which cytoskeleton filament makes up the centriole and is used for mitosis and the formation of cilia/flagella in eukaryotes?

Microtubules