Membrane that controls movement of substances into and out of the cell; site of cell signaling.
Site of modification, sorting, and secretion of lipids and proteins.
Packages materials into SECRETORY vesicle.
Site of ATP synthesis.
Involved in the synthesis, modificiation and breakdown of several types of cell brown fat cells. Generate heat known as brown fat cells which serve as "heating pads" that help to revive hibernating animals and protects us.
PROKARYOTES, Outer glatinous covering. Traps water andhelps protect bacteria form drying out.
PROKARYOTES, A thick, gelatinous glycocalyx that helps them avoid being destroyed by the animal's immune system or aid in the attachment to cell surfaces.
Includes Nuclear envelope, endoplasmic reticulum, Golgi Apparatus, Lysosomes, vacuoles, plasma membrane and peroxisomes
The internal structure shared by flagella and cilia. Contains microtubules, the motor protein dynein, and linking proteins. Microtubules form an arrangement called a 9+2 array.
Tow parts: the nuclear lamina (intermediate filaments that line the inner nuclear membrane) and the internal nuclear matrix.
Serves to organize the chromosomes within the nucleus
A network of membranes that form the form flattened, fluid-filled tubules of the Endoplasmic Reticulum.
Entire route where Proteins destined for secretion are synthesized into the ER, travel to the Golgi, and then are transported by vesicles.
Mitochondria and chloroplasts. They can grow and divide to reproduce themselves, but they are not completely autonomous because they depend on other parts of the cell for their internal components.
A third system of membranes, forms many flattened fluid-filled tubules that enclose a single convoluted compartment within a chloroplast.
The compartment of the chloroplast that is enclosed by the inner membrane but outside the thykaloid membrane.
Chromoplasts: synthesize and store the yellow, orange and red pigments known as carotenoids. Give fall leaves their color.
Leucoplasts: Lack pigment
Amyloplast: A leucoplast that synthesizes and stores starch. Common in roots and tubers.
When the synthesis of a protein is halted until the ribosome is bound to the ER membrane. Sorting process begins while translation is occuring.
Cotranslational Sorting of Protein @ER
1. Polypeptide contains an ER signal sequence
2. ER signal sequence recognized by a protein called signal recognition particle (SRP.)
3. SRP pauses translation, binds to a recepton in ER and docks ribosome over a channel protein.
4.SRP leaves and polypeptide threaded through channel to cross ER membrane; ER signal sequence removed by signal peptidase.
Vesicle Formation of Proteins
1. Vesicle formation facilitated by coat proteins.
2.When vesicle buds from membrane, v-snares incorporated into the vesicle membrane.
3. Vesicle released, coat is shed, v-snares in membrane are recognized by t-snares in target membrane.
4. Vesicle fuses with membrane containing the t-snares.
Post-translational protein sorting to nucleus, peroxisome, mitochondria and chloroplasts
1.Chaperone proteins keep protein unfolded.
2. Matrix-targeting sequence binds to receptor.
3. Chaperones are released as protein is transferred to a channel in the outer membrane.
4.Protein is transfered to a channel in the inner membrane.
5.Chaperones bind to protein as it enters the matrix.
6.Matrix-targeting sequence cleaved by enzyme.
7.Protein is completely threaded into the matrix
8. Chaperones are released, and protein folds into its 3-D shape.
4 Interacting parts of a Eukaryotic Cell
the interior of the nucleus
the endomembrane system
the semi-autonomous organelles
Occurs in Archaea
Carbohydrate attached to the amino acid asparagine in polypeptide chain
1.Group of 14 sugar molecules built onto a lipid called dolichol
2. Carb. tree transferred to asparagine, peptide synthesized into ER lumen through a channel protein.
3. An ER enzyme, oligosaccharide transferase, recognizes sequence and transfers carb tree form dolichol to asparagine
Occurs in the Golgi apparatus
Involves the addition of a string of sugars to oxygen atom of serine or threonine
Important for production of proteoglycans (highly glycosylated proteins that are secreted from cells and help to organize the extracellular matrix)
Degradation of mRNA:
1. Tail removed
2. 5'cap removed
3. Removes nucleotides starting at the 5' end and moving toward the 3' end.
Break Down Protein in Proteasome
1.String of ubiquitns attached to a target protein.
2.Protein w/ubiquitin directed to the proteasome.
3.Protein is unfolded by enzymes in the cap and injected into the core proteasome. Ubiquitin released back into the cytosol.
4.Protein is degraded to small peptides and amino acids.
5.Small peptides and amino acids are recycled back to the cytosol.
Cytoplasm v.s. Cytosol
Cytoplasm=region enclosed by the plasma membrane, includes they cytosol and organelles
Cytosol=region of cell outside membrane-bound organelles but inside the plasma membrane
Smooth ER Liver Cells
Enzymes in smoother ER of liver detoxify evil molecules, convert hydrophobic toxic molecules into hydrophilic molecules, excreted from body
Provides surface area for enzymes in metabolic roles (liver cells)
Accumulation of Ca2+ ions
Synthesis of phospholipids and lipids (like cholesterol, which makes testosterone and estrogen)
Inserts proteins into the ER
Attaches carbs to proteins and lipids (Glycosylation)
Found in animal cells, lyse macromolecules
Contain acid hydrolases that break down carbs, proteins, lipids and nucleic acids
Break down stuff from endocytosis
Breakdown molecules by removing H or adding O
makes hydrogen peroxide H2O2<-- use catalase enzym to break down to H20 and O2