Flashcards in Biochem Ch 1-3 Deck (177)
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1
chemo drugs that act in S phase
- methotrexate, 5-flurouracil, hydroxyurea
- interfere with thiamine (only in DNA) synthesis
2
chemo drugs that act in G2 phase
bleomycin
3
chemo drugs that act in M phase
paclitaxel, vincristine, vinblastine
4
non cell-cycle specific chemo drugs
cyclophosphamide, cisplatin
5
Nucleoside
base + 5C sugar
6
Pyrimidines
- Cytosine, uracil, thymine
- "CUT the Py"
- if you deaminate C, you get U
- Uracil is only in RNA
- difference between U and T = T has a methyl group
- Thymine is only in DNA
- Cytosine is in both DNA/RNA
- structure is 1 ring
- "More complex name, more simple structure"
7
Nucleoside of Adenine and Guanine
Adenosine (deoxyadenosine), Guanosine (deoxyguanosine)
8
Nucleotide
base + 5C sugar + phosphate
9
Nucleoside of cytosine
cytidine (deoxycytidine)
10
nucleoside of uracil
uridine (deoxyuridine)
11
nucleoside of thymine
deoxythymidine (BC only in DNA)
12
MOA for daunorubicin and doxorubicin
- Anti tumor drugs used to treat leukemias
- intercalating between the bases of DNA, thereby interfering with the activity of topoisomerase II and preventing proper replication of the DNA
13
Purines
- Adenine and Guanine
- if you deaminate A you get G
- Purines have 2 ringed structures
- "PURe As Gold"
14
MOA of cisplatin and use
- antitumor drug used to treat bladder and lung tumors
- bind tingtly to the DNA, causing structural distortion and malfunction
15
negative vs positive supercoiling
negative superoiling = DNA is wound MORE LOOSELY than watson-crick DNA
positive supercoiling = DNA is wound MORE TIGHTLY than watson-crick DNA
16
How to topoisomerases work? and example
They change the amount of supercoiling in DNA molecules by making transient breaks in DNA strands by alternately breaking and resealing the sugar-phosphate backbone.
ie E. Coli DNA gyrase (DNA Topoisomerase II) can introduce negative supercoiling in DNA
17
nucleosome
DNA wrapped 2x around 8 histones: (2 H2A, 2 H2B, 2 H3, 2 H4 = a histone octamer)
H1 = associated w the linker DNA found between the nucleosomes to help package them into a solenoid-like structure (a thick 30 nm fiber)
18
what amino acids predominate in histones?
lysine and arginine. both have a + charge and confer a positive charge on the proteins
19
Why does DNA have a negative charge?
because between every 5C sugar there is a phosphate with a negative charge
20
euchromatin
- light staining
- transcripturally active genes
- apoptois
- more opened and available for gene expression
- ie insulin gene in pancreas
21
heterochromatin
- dark staining
- transcripturally inactive genes
- highest order packaging
- condensed and associated with areas of chromosomes that are NOT expressed
- ie insulin gene in muscle
- MITOTIC DNA = MOST CONDENSED DNA to allow separation of the sister chromatids= no gene expression.
22
anything ending in "-in"
protein!
23
Double stranded DNA associates together via
hydrogen bonding
24
nucleotide
phosphate group is attached to the 5' C of a nucleoside
25
characteristic features of eukaryotic cell death (in nucleus) by apoptosis
endonuclease activation and chromatin fragmentation
26
circular DNA double helices
- bacterial chromosome
- bacterial plasmid
- mitochondrial chromosome
27
most viral genomes are
SSDNA
- an example of an exception = parvovirus
28
mitochondrial DNA is found in the
cytoplasm (like in bacteria)
29
RNA is made in the (location)
nucleus and is moved to the cytoplasm
30