Chapter 4 Flashcards
wWhat does the cytoplasm consist of ?
contains sugars, amino acids and proteins
what is the cytoplasm?
is a semifluid matrix
what are ribosomes?
a protein that synthesizes all cellular proteins.
what is the plasma membrane?
it encloses the cell and separates its contents and from the surroundings
Explain protein transport through the endomembrane systems?
proteins synthesized by ribosomes on the RER are translocated into the infernal compartment of the ER. these proteins may be used at a distant location within vesicles that bud off the ERR. These transport vesicles travel to the cis face of the Golgi apparatus. there they can be modified and packaged into vesicles that bud off the trans face of the Golgi Apparatus. Vesicles leaving the trans-face transport proteins to other locations in the cell or fuse with the plasma membrane , releasing their contents to the extracellular environment.
what are lysosomes?
digestive system of the cell.
what are Peroxisomes?
They are microbodies that contain enzymes used to oxidize fatty acids.
what is the function of the mitochondria?
Store or generates ATP
what is the function of the Nucleus?
instructions of protein synthesis can cell reproduction, contains genetic information.
what is the cytoskeleton?
network of protein filaments
what is a chromatin?
the material of which the chromosomes of organisms other than bacteria (i.e., eukaryotes) are composed. It consists of protein, RNA, and DNA.
what does the rough er do?
The rough endoplasmic reticulum has on it ribosomes, which are small, round organelles whose function it is to make those proteins.
what are Actin filaments?
polymers of actin monomers (G-actin). Actin filaments form the core of thin filaments in muscle cells.
explain microtubules.
It is the largest of the cytoskeleton elements, are hollow tubes about 25nm in diameter, each composed of a ring of 13 protein protofilaments.
what is the flagella?
cellular extinction with 9+2 arrangement pairs of microtubules
what is the function of the smooth ER?
It synthesizes lipids, phospholipids as in plasma membranes, and steroids.
what and where is the basal body?
its just situated below the point where the flagellum protrudes from the surface the cell.
what are primary walls?
they laid down when the cell is still growing
what are Middle Lamella?
between the walls of adjacent cells a sticky substance, it glues cells together.
what are secondary walls?
they are deposited inside the primary walls fully expanded cells
what is the function of a surface maker?
identifying cells
what is the structure of a surface maker?
variable integral proteins or glycolipids in plasma membrane
what is the function of an desmosome?
creates strong flexible connections between cells, found in vertebrates.
what is the structure of desmosome?
variant cadherins, bind to intermediate filaments of cytoskeleton.
what is the function for adheres junctions?
connects cells together, oldest form of cell junction, found in all multicellular organisms
what is the structure of adheres junctions?
classical cadherins, bind to microfilaments of cytoskeleton
what is the function of a hemidesmosome/ focal adhesion?
provides attachment to substrate
what is the structure of the hemidesmosome/ focal adhesion?
integrin proteins bind cell to extracellular matrix
what is the function of a gap Junction?
Allows passage of small molecules from cell to cell in a tissue
what is the structure of a gap junction?
6 transmembrane connexon/ pannexin proteins creating a pore that connects cells
what is the function of a plasmodesmata?
communicating junction between plant cells
what is the structure of the plasmodesmata?
cytoplasmic connections between gaps in adjoining plant cell walls.
Explain the cadherin- mediated junction?
The cadherin molecule is anchored to actin in the cytoskeleton and passes through the membrane to interact with the cadherin of an adjoining cell
how does the phospholipid bilayer work?
