Describe the basic structure of a cell and list the functions of the major organelles.

Plasma membrane- acts as a barrier preventing free movement of most material into or out of the cell

Cytoplasm- carry out glycolysis and protein synthesis Cytoskeleton

Centrioles- pull the chromosomes apart for cell division

Nucleus- separates the nuclear material from the cytoplasm and contains chromatin

Nucleolus- where ribosomal RNA is synthesized and aggregates with ribosomal proteins to form large and small ribosomal subunits

Ribosomes- organelle that performs protein synthesis

                        i.Free ribosomes- produce cytoplasmic proteins

                        ii.Bound ribosomes- produce proteins that become a part of membranes

Endoplasmic reticulum- manufacturing, transportation and processing network for cell

                          i.Rough- synthesis of membrane proteins, secreted proteins and proteins for some organelles

                           ii.Smooth- synthesis of lipids, Detoxification of drugs, metabolites and toxins

Golgi apparatus- receiving, processing, sorting, shipping

Secretory vesicles- Cell secretions - e.g. hormones, neurotransmitters - are packaged in secretory vesicles at the Golgi apparatus. The secretory vesicles are then transported to the cell surface for release

Mitochondria- produce ATP

Lysosomes- help digest damaged cellular components and material brought into the cell by pinocytosis and digestive enzymes

Peroxisomes - contain oxidative enzymes that degrade fatty acids and other compounds producing hydrogen peroxide

Proteasomes - degrade unneeded or damaged proteins by proteolysis

Where does glycolysis occur?

What is the purpose of the TCA (Krebs) cycle and the electron transport system?  

Why do mitochondria need an inner and outer membrane?

Describe the mechanism of action of the metabolic poisons Na Azide and dinitrophenol.

Þ  DNP uncouples oxidative phosphorylation (inhibits ATP production) by acting as a proton ionophore,  carrying protons across the mitochondrial membrane and decreasing the proton gradient

Þ  Azide is a metabolic poison that inhibits cytochrome oxidase by binding irreversibly to the heme cofactor

Describe the physiological processes involved in protein synthesis.

mRNA is transcribed from a gene, introns are spliced from the mRNA, the mRNA is transported out of the nucleus thru the nuclear pore, ribosomal subunits bind the mRNA, protein chain terminated at stop codon.

What is a gene? What is a transcription factor?

                                         Gene- unit of heredity. It is normally a stretch of DNA that codes for a type of protein or for an RNA chain that has a function in the organism

         Transcription factor- a protein that binds to specific DNA sequences

  What is the function of mRNA? What is the function of tRNA? What is the function of rRNA? What is a codon?

mRNA is the molecule used to read the DNA sequence and transfer the information.

  rRNA holds the mRNA in place for tRNA. 

 tRNA is the reader of the mRNA sequence and transfers the a.a. to the protein sequence. 

 Codon- a series of three adjacent bases in one polynucleotide chain of a DNA or RNA molecule, which codes for a specific amino acid

  a covalent bond that is formed between two molecules when the carboxyl group of one molecule reacts with the amino group of the another

Þ            an amino acid that cannot be synthesized by the organism (usually referring to humans), and therefore must be supplied in the diet.

                                          i.Phenylalanine

                                         ii.Valine

                                        iii.Threonine

                                       iv.Tryptophan

                                        v.Isoleucine

                                       vi.Methionine

                                      vii.Histidine

                                     viii.Arginine

                                       ix.Leucine

                                        x.Lysine

What is an acidic amino acid side chain?

 Describe the three types of proteins of the cytoskeleton.

microtubules: composed of tubulin

form cytoskeletal framework and centrioles, cilia, flagella

Interact with motor proteins (kinesin, dynein)

intermediate filaments: (hair, skin), neurofilament (nerve cells),

microfilaments: actin Interact with motor proteins (myosins)

Which cytoskeletal filaments are formed from actin?  From tubulin?

actin- Microfilaments

tubulin- microtubules

Endocytosis: the internalization of substances includes both phago and pinocytosis and refers to the uptake of material thru the plasma membrane by formation of a vesicle.

 Exocytosis: the membrane of a vesicle fuses with the plasma membrane and the content of the vesicle is expelled from the cell.

Secretion: only occurs in leukocytic, neuronal, exocrine, endocrine cells, etc; occurs in response to specific signals, the products are then stored in vesicles from the golgi, then are transported to the membrane and released

Kinesins bind to secretory vesicles on one end and on the other with microtubules for  transport and uses ATP

Dyneins: proteins connecting adjacent pairs of microtubules.

 Contact inhibition is the natural process of arresting cell growth when two or more cells come into contact with each other. Oncologists use this property to distinguish between normal and cancerous cells.

 What drug inhibits mitotic spindle formation?

Colchicine

Vinchristine (Oncovine)

Vinblastine

It binds tubulin, thereby inhibiting the assembly of microtubules.

During which does the cell mainly produce tissue specific proteins?

 Describe the mechanism of action of 5-flurouracil (5-FU).