General Flashcards
What proceesing do zymogens undergo to become mature peptides
removal of N or C terminal propeptides
which part of trna binds to the amino acid
5’ CCA 3’ acceptor stem
what does p 53 induce and what does it modulate
p21 which inhibits CDKs (inhibit G1 to s progression)
Rb is what when phophorylated
inactive, it allows progression from G1 to S (remember the cop getting bribed)
WHich cell types remain in G0
permenant cells, regenrate from stem cells; neurons skeletal and cardiac muscle and RBC
Which cell type never goes to g0
labile- divide rapidly with short g1 and are most affected by chemotherapy
bone marrow, gut, skin, hair, germ cells
Where is g0 phase
between m and S allternate path before g1
What are nissel bodies
rer in neurons
WHich cells are rich in RER
mucus secreting goblet cells of smal intestine and antibody scereting plasma cells
Which type of proteins are mainly made in RER
secretory exported proteins
What Type of proteins are mainly made in the ser/other roles
steroids
also the site of detoxification of drugs and poisons
Which cells have a lot of SER
liver hepatocytes and steroid homroon producing cells of the adrenal cortex and gonads
The golgi modifies what 3 amino acids and how
asparagine: modifies n oligosaccharides
Serine: adds o oligosaccharides
threonine: adds o oligosaccharides
What are SRPs if they are absent what happens
signal recognition particles which traffic proteins from ribosome to rer
if absent proteins accumulate in the cytosol
Which vesicular protein goes from golgi –> golgi and cis golgi to ER
COP1 (retrograde
Which vesicular protein goes from ER –> cis golgi
COP2 (anterograde)
WHich vessicular protein goes from trans golgi –> lysosomes and plasma membrane –> endosomes
Clathrin (clathrin coated pits for endocytosis)
What disorder have proteasomes been implicated in
Parkinsons defect in ubiquitin proteasome system in some cases
MEsechymal tissue/ tumors (eg sarcoma), endometrial carcinoma, renal cell carinoma, meningioma stain with what immunohistochemical stain
vimentin
Muscel tumors like rhabdomyosarcoma stain with what immunohistochemical stain
Desmin
Epithelial tumors like Squamous cell carcinoma stain with what immunohistochemical stain
Cytokeratin
Neuroglia tumors like astrocytoma and glioblastoma stain with what immunohistochemical stain
GFAP
Neurons/neuronal tumors like neuroblastoma stain with what immunohistochemical stain
Neurofilament
what does ouabain inhibit and how
sodium ppotassium pump by binding to the k site
WHich drugs act on microtubules (6)
Mebendazole Griseofulvin Colchicine Vincristine Vinblastine Paclitaxel
methylation of what represses transcription
CpG islands in dna
acetylation of histones does what
relaxews dna coiling allowing for transcription
Which amino acids are necessary for purine synthesis
Glycine, Aspartate, glutamine
Which 2 amino acids are histones rich in
lysine and arginine
Complete the blanks: Deamination of \_\_ makes \_\_ Methylation of \_\_ makes \_\_ Deamination of \_\_ makes \_\_ (with regards to purines and pyrimidines
1: Cytosine; uracil
2: Uracil; Thymine
3: adenine: guanine
dWhat drug disrups both purine and pyrimidine syhtesis and how
hydroxyurea by inhibiting ribonucleotide reductase
Which drug inhibits dihydroorotate dehydrogenase and what cycle does it disrupt
Leflunomide
Disrupt pyrimidine synthesis
What drugs (3) inhibit dihydrofolate reductase and what cycle do they disrupt
Methotrexate (humans)
Trimethoprim (bacteria)
Pyrimethamine (protozoa)
Disrupt pyrimidine synthesis
Which drug inhibits thymidylate synthase and what cycle does it disrupt
5-FU
Disrupt Pyrmidine synthesis
Which drugs (2) inhibit inosine monophosphate dehydrogenase and what cycle does it disrupt
Mycophenolate
Ribavirin
Disrupt purine synthesis
fluoroquinolones inhibit what prokaryotic enzymes
topoisomerase II (dna gyrase) and topoisomerase IV
Which orgainisms have multiple origins of replication
Eukaryotes (pro have 1)
which organisms have multiple open reading frames in rna
prkaryotes
drugs blocking DNA replication often have a modified what
3’OH
which polymerase has 5’ 3’ exonuclease activity and what is its role
DNA polymerasse 1 ( only in prokaryotes)
degrades RNA primer and replaces it with DNA
(also has the 3’5’ exonuclease activity like pol III)
Which organisms yhave telomerase and what type of enzyme is it
Only eukaryotes
RNA dependent DNA polymerase (adds dna to 3’ ends of chromosomes)
dfifferentiate transition and transversion
transition is purine to purine for example
transverison is purine to pyrimidine for example
what are 2 examples of diseases with a frameshift mutation
duchennes and tay sachs
what are some disorders with ssplice site mutations
rare cause of cancers, dementia, epilepsy and some types of Beta thal
In the following scenarios describe the protein binding and expression of genes occuring in the lac operon
1: low glucose, lactose present
2: high glucose, lactose unavailable
3: low glucose, lactose unavailable
4: high glucose, lactose available
1: CAP (catabolite activator protein) bound; repressor not bound; genes expressed strongly
2: CAP not bound; repressor bound; no gene expression
3: CAP bound; repressor bound; no gene expression
4: CAP not bound; repressor not bound; low level of gene expression
Pressence of lactose/allolactose removes repressor
Presence of cAMP activates CAP and binds it (glucose suppresses adenylate cyclase= glucose high low camp)
During which phase of the cell cycle do these single strand repair mechanisms function
1: Nucleotide excision repair
2: base excision repair
3: Mismatch repair
1: G1 phase of cell cycle
2: Throughout cell cycle
3: Predominantly in G2 phase of cell cycle
