the cell Flashcards
what is the cytoskeleton
-Interior framework of the cell
-Supports the shape of the cell
-Anchors organelles (Ex: Mitochondria) to fixed locations
name the 3 different types of protein fibres
1) Long slender microfilaments (actin)
2) Hollowed tubes called microtubles (tubulin)
3) Thick ropes called fibrous sub units or intermediate filaments
what are cilia and flagella
1) Cilia - The humorous appendages that propel single celled protists
-Some cells of multicellular organisms have cilia or flagella as well
2) Flagella - Other protists may move using flagella
-They are longer than cilia
-Usually limited to one or a few per cell
basal body what is it
-The microtubule assembly extends into an anchoring structure called a basal body
-Basal body consists of a ring of 9 microtubule triplets
what does the nucleus do
-Cells control center
-Directs all of the cell’s activities
-The genetic library in where the hereditary info is stores
-Contains most of cell’s DNA (Chromosomes =DNA associated with many proteins)
-Controls cells activities by directing protein synthesis (makes RNA)
what does the nuclear envelope do
-A double membrane
-Porous to allow material to flow in/out
-Attach to cell membranes of endoplasmic reticulum
what do ribosomes do
-Uses nucleus instructions to synthesize proteins
-Cells that make a lot of proteins (large # of ribosomes)
(EX: A human pancreas all producing digestive enzymes may contain a few million ribosomes)
endomembrane system what does it do
-Some membranes are related by the transfer of membrane segments by tiny vesicles
-Vesicles = Sacs made of membrane
what does the ER do
-Endoplasmic = within the cytoplasm
-Reticulum = little net
-Weaves in sheets through the interior of the cell, creating a series of channels and interconnections
SURFACE OF THE ER:
-Where the cell manufactures many carbohydrates and lipids
-Also where cell makes proteins intended for export
