1.If a cell were entering mito
1.If a cell were entering mitosis, how would you expect the rateof elongation as a function of monomer concentration to change formicrotubules, intermediate filaments, and microfilaments? Pleaseexplain your answer.
2.
- A cell is treated with cytochalasin. What effect would youpredict this would have on the rate of elongation as a function ofmonomer concentration for microtubules, intermediate filaments andmicrofilaments? Please explain your answer.
3.
- Suppose a mutation to the gene coding for actin made the T formmore stable. What would this do microfilaments? Would you expectthe mutation to be harmful? Please explain your answers.
Answer:
1.Polymerization of actin monomers into filaments inconcentration dependent. Below a certain concentration, actinmonomers remain as monomers, but above a certain concentrationmonomers start to polymerize into filaments.actin filaments, likemicrotubules, are polarized with the ends having differentbiochemical properties. The plus end is more stable and is the endat which new monomer are added, so filaments grow from their plusend.Intermediate filaments (IFs) provide tensile strength to cells,as they resist stretching. In contrast to tubulin and actin, IFscomprise a large class of proteins that are expressed in atissue-dependent manner. IFs are not polarized and do not supporttransport by motor proteins.Cell division beginsalong the cell’s equator, between the twochromosomal pole formed duringnuclear division.Microfilaments help the cell laydown new membrane and divide into two daughtercells.Microfilaments are highways for myosinproteins that motor along the length of a strand, using the cell’senergy storage molecule, adenosine triphosphate, or ATP, as fuel.Myosin movement pinches one cell into two.