Card Set Information
made up of a web of protein fibers. It holds the cell together and keeps the cell's membranes from collapsing
fluid surrounding the cytoplasm organelles, internal membranes and cytoskeleton fibers
What is the cytoskeleton composed of?
an intricate network of protein fibers anchored to the inside of the plasma membrane. They link one region of the cell to another like steel beams in a building to add support
3 kinds of cytoskeleton fibers
1. long slender microfilaments made of protein actin
2. Hollow tubes called microtubules made of protein tubulin
3. thick ropes of protein called intermediate fibers.
part of the cytoskeleton that form a network just beneath the cell surface that is anchored to the membrane proteins embedded within the cell membrane
part of the cytoskeleton that acts as a highway system for the transportation of information from the nucleus to different parts of the cell. RNA molecules are transported down by MOTOR PROTEINS
part of the cytoskeleton that provides a frame on which ribosomes and enzymes can be confined to particular regions of the cell.
Are cell membranes like an egg shell or soap bubble?
They are fluid like a soap bubble-
They cause the fluidity of cell membrane. Form a barrier that separates the inside of the cell from the outside of the cell. It allows only certain substances to pass thru or leave the cell.
What is the importance of how phospholipids interact with water?
It has both a polar "head" which is attracted to water and 2 nonpolar "tails" which are repelled by water.
in a cell membrane the phospholipids are arranged in a DOUBLE layer
different types of membrane proteins
1. Marker proteins-attach to a carbohydrate on the cell's surface (liver or heart)
2. Receptor proteins-bind specific substances such as signal molecules outside the cell
3. Enyzmes-embedded in cell membrane and involved in biochemical reactions in the cell
4. transport protein-aid in the movement of substances into and out of the cell
controlls most of the eukaryotic cell's function.
What is the nucleus surrounded by?
a double membrane called the nuclear envelope or the neclear membrane. It is made of 2 lipid bilayers and separates the nucleus from the cytoplasm
scattered over the nuclear envelope--these are small channels that substances move through. RNA moves