Biochem

Front 1

Inhibits ribonucleotide reductase

Back 1

hydroxyurea

Front 2

inhibits de novo purine synthesis

Back 2

6-MP

Front 3

inhibits thymidylate synthase

Back 3

5-FU

Front 4

inhibits tetrahydrofolate reductase

Back 4

MTX (humans)
trimethoprim (bacteria)

Front 5

accumulation of carbamoyl phosphate --> excess orotic acid and hyperammonemia is caused by

Back 5

ornithin transcarbamoylase deficiency (in urea cycle)

Front 6

excess orotic acid without hyperammonemia is caused by

Back 6

orotic aciduria (inability to convert orotic acid to UMP)

Front 7

retardation, self-mutilation, aggression, hyperuricemia, gout, choreoathetosis

Back 7

Lesch-Nyhan syndrome = deficiency of HGPRT

("He's Got Purine Recovery Trouble")

Front 8

inhibit DNA gyrase (DNA topoisomerase)

Back 8

fluoroquinolones

Front 9

Prevent strands of DNA from reannealing during replication

Back 9

single stranded binding proteins

Front 10

In which direction is DNA read?
In which direction is DNA synthesized by DNA pol?

Back 10

3'-->5'
5'-->3'

Front 11

dry skin with melanoma, other cancers; inability to correct thymidine dimers

Back 11

xeroderma pigmentosa =
mutated nucleotide excision repair (endonucleases)

Front 12

glycosylases recognize/remove damaged bases --> AP endonuclease removes empty sugar --> gap is filled (polymerase) and resealed (ligase)

Back 12

base excision repair

Front 13

mutated in hereditary non-polyposis colorectal cancer (HNPCC)

Back 13

mismatch repair (recognition of "new strand" because it's unmethylated) --> removal of mismatched nucleotides on that strand

Front 14

repair of double stranded break?

Back 14

non-homologous end joining

Front 15

Which RNA is most abundant?

Back 15

rRNA

Front 16

Which RNA is largest?

Back 16

mRNA

Front 17

Which RNA is smallest?

Back 17

tRNA

Front 18

In which direction is mRNA read?

Back 18

5'-->3'

Front 19

In which direction is protein synthesized?

Back 19

N -->C

Front 20

Start codon(s)?

Back 20

AUG - methionine/f-met

Front 21

mRNA stop codon(s)?

Back 21

UGA - U Go Away
UAA - U Are Away
UAG - U Are Gone

Front 22

Effect of ingesting alpha-amanitin in death cap mushrooms?

Back 22

Inhibits RNA polymerase II (which makes mRNA) --> liver failure

Front 23

What RNA modifications are completed in the nucleus following transcription?

Back 23

1) 5' cap (7' methylguanosine)
2) 3' polyadenylation
3) intron splicing

Front 24

antibodies to spliceosomal snRNPs are associated with?

Back 24

lupus

Front 25

Where are secretory (exported) proteins found?

Back 25

RER

Front 26

Where does N-linked oligosaccharide addition to proteins take place

Back 26

RER

Front 27

What types of cells are rich in RER?

Back 27

Neurons (Nissl bodies make peptide neurotransmitters and enzymes)
Goblet cells (mucus)
Plasma cells (antibodies)

Front 28

Where are cytosolic and organellar proteins synthesized?

Back 28

Free ribosomes

Front 29

Where are steroids synthesized and drugs/poisons detoxified?

Back 29

smooth ER

Front 30

What cells are rich in smooth ER?

Back 30

hepatocytes
steroid-hormone producing cells of adrenal cortex

Front 31

N-oligosaccharides are modified on which amino acid(s) in the Golgi?

Back 31

asparagine

Front 32

O-oligosaccharides are modified on which amino acid(s) in the Golgi?

Back 32

serine and threonine

Front 33

What is added to lysosomal proteins in the Golgi?

Back 33

mannose-6-phosphate (targets them to the lysosome)

Front 34

What actions regarding proteoglycans take place in the Golgi?

Back 34

Assembly of proteoglycans from core proteins
Sulfation of sugars in proteoglycans

Front 35

Which amino acid on proteins gets sulfated the Golgi?

Back 35

Tyrosine

Front 36

Function of COP I trafficking protein?

Back 36

retrograde trafficking (from Golgi to ER)

Front 37

Function of COP II trafficking protein?

Back 37

anterograde trafficking (from RER to cis-Golgi)

Front 38

Function of clathrin trafficking protein?

Back 38

trans ("distal")-Golgi --> lysosomes, plasma membrane --> endosomes (receptor-mediated endocytosis)

Front 39

coarse facial features, clouded corneas, restricted joint movement, high plasma levels of lysosomal enzymes

Back 39

I cell disease (failure of addition of mannose-6-phosphate --> enzymes are secreted rather than being targeted to lysosome)

Front 40

Direction of movement of cargo relative to microtubule:
Dynein?
Kinesin?

Back 40

Dynein - retrograde (+ to -)
Kinesin - anterograde (- to +)

Front 41

Name the drugs in each of the following groups that act on microtubules:
- antihelminthic
- anti breast cancer
- anti cancer
- antifungal
- anti-gout

Back 41

- antihelminthic: Mebendazole
- anti breast cancer: Paclitaxel
- anti cancer: vincristine/vinblastine
- antifungal: griseofulvin
- anti-grout: colchicine

Front 42

Recurrent pyogenic infections, partial albinism, peripheral neuropathy

Back 42

Chediak-Higashi syndrome (microtuble polymerization defect --> decreased phagocytosis)

Front 43

infertility, bronchiectasis, recurrent sinusitis, situs inversus

Back 43

Kartagener's syndrome (dynein arm defect --> cilia immotility)

Front 44

What cytoskeletal element(s) comprise:
microvilli

Back 44

actin and myosin

Front 45

What cytoskeletal element(s) comprise:
muscle contraction

Back 45

actin and myosin

Front 46

What cytoskeletal element(s) comprise:
cytokinesis

Back 46

actin and myosin

Front 47

What cytoskeletal element(s) comprise:
adherens junctions

Back 47

actin and myosin

Front 48

What cytoskeletal element(s) comprise:
cilia

Back 48

microtubules

Front 49

What cytoskeletal element(s) comprise:
flagella

Back 49

microtubules

Front 50

What cytoskeletal element(s) comprise:
mitotic spindle

Back 50

microtubules

Front 51

What cytoskeletal element(s) comprise:
neurons

Back 51

microtubules

Front 52

What cytoskeletal element(s) comprise:
centrioles

Back 52

microtubules

Front 53

What cytoskeletal element(s) comprise:
vimentin

Back 53

intermediate filaments

Front 54

What cytoskeletal element(s) comprise:
desmin

Back 54

intermediate filaments

Front 55

What cytoskeletal element(s) comprise:
cytokeratin

Back 55

intermediate filaments

Front 56

What cytoskeletal element(s) comprise:
glial fibrillary acid proteins (GFAP)

Back 56

intermediate filaments

Front 57

What cytoskeletal element(s) comprise:
neurofilaments

Back 57

intermediate filaments

Front 58

What cell type is stained for with the following:
vimentin
desmin
cytokeratin
GFAP
neurofilaments

Back 58

vimentin - connective tissue
desmin - muscle
cytokeratin - epithelial cells
GFAP - neuroglia
neurofilaments - neurons

Front 59

What type of collagen is most abundant?

Back 59

Type I

Front 60

What type of collagen comprises dentin, fascia, cornea, and late wound repair?

Back 60

Type I

Front 61

What type of collage comprises bone and tendon?

Back 61

Type I

Front 62

What type of collagen comprises cartilage?

Back 62

Type II

Front 63

What type of collagen comprises vitreous body and nucleus pulposus

Back 63

Type II

Front 64

What type of collagen is also known as reticulin?

Back 64

Type III

Front 65

What type of collagen is found in blood vessels?

Back 65

Type III (reticulin)

Front 66

What type of collagen is found the uterus and in fetal tissue?

Back 66

Type III (reticulin)

Front 67

What type of collagen is found in granulation tissue?

Back 67

Type III (reticulin)

Front 68

What type of collagen comprises basement membranes/basal lamina?

Back 68

Type IV

Front 69

Which step of collagen synthesis requires vitamin C?

Back 69

Hydroxylation (of specific proline and lysine residues on pre-procollagen)

Front 70

Which step of collagen synthesis is impaired in osteogenesis imperfecta?

Back 70

Glycosylation of lysine residues to form procollagen triple helix

Front 71

Which step of collagen synthesis is impaired in Ehlers-Danlos syndrome?

Back 71

cross-linkage of tropocollagen to make collagen fibrils

Front 72

hyperextensible skin, tendency to bleed/easy bruising, hypermobile joints

Back 72

Ehlers-Danlos syndrome (usually Type III collagen)

Front 73

multiple fractures with minimal trauma, blue sclerae, hearing loss, dental imperfections

Back 73

osteogenesis imperfecta (usually Type I collagen)

Front 74

progressive nephritis and deafness
abnormal Type IV collagen

Back 74

Alport syndrome

Front 75

alpha-1-antitrypsin deficiency -->

Back 75

emphysema
(doesn't inhibit elastase --> breaks down elastin in lungs)

Front 76

defect in fibrillin -->

Back 76

Marfan's syndrome
(fibrillin scaffoling + tropoelastin = elastin)

Front 77

What are the 3 steps of PCR?

Back 77

1) Denaturation
2) Annealing
3) Elongation

Front 78

DNA probe binds to DNA sample

Back 78

Southern blot

Front 79

DNA probe binds to RNA sample

Back 79

Northern blot

Front 80

Labeled antibody binds to sample protein

Back 80

Western blot

Front 81

Used to profile gene expression levels or detect SNPs

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microarray

Front 82

nature and severity of phenotype vary between individuals

Back 82

variable expression

Front 83

not all individuals with mutant genotype have mutant phenotype

Back 83

variable penetrance

Front 84

1 gene > 1 effect

Back 84

pleiotropy

Front 85

A heterozygote produces a nonfunctional altered protein that prevents the normal gene product from functioning

Back 85

dominant negative mutation (e.g. Tx factor)

Front 86

Tendency for certain alleles at 2 linked loci to occur together more often than expected by chance. Measured in a population

Back 86

linkage disequilibrium

Front 87

Mutations at different loci produce the same phenotype

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locus heterogeneity
(e.g. Marfan's, MEN2B, homocysteinuria
albinism)

Front 88

Variable expression of mitochondrial disease due to presence of both normal and mutated mtDNA

Back 88

heteroplasmy

Front 89

Degeneration of retinal ganglion cells and axons --> loss of central vision
Mitochondrial inheritance

Back 89

Leber's hereditary optic neuropathy

Front 90

Phosphate wasting in proximal tubule
X-linked dominant inheritance

Back 90

Hypophosphatemic rickets