Test 28- BC

Question 1

negative G

Answer 1

Free energy of products is LOWER than that of substrates

favors PRODUCT formation

Question 2

positive G

Answer 2

free energy of products is HIGHER than substrates

favors SUBSTRATE formation

Question 3

Deletion/insertion of a number of base pairs (nucleotides) that are NOT multiples of three (126> 124 bp)

Answer 3

FRAME SHIFT MUTATION

alter reading of genetic code> non functional proteins

Question 4

MC CFTR mutation

Answer 4

codon deletion of phenylalanine at position 508

**also possible to get frameshift mutation caused by 2 bp deletion in the CFTR protein

Question 5

codon deletion

Answer 5

deletion of one or more entire codon (genetic triplet code)

Question 6

amatoxin

Answer 6

found in poisonous mushroom

Inhibits RNA pol II halting mRNA synthesis

(RNA pol II makes mRNA, largest> MASSIVE)

Question 7

pathology that occurs secondary to x linked mutation affecting the PRPP synthetase gene leading to an INCREASED substrate concentration

Answer 7

Gout

occurs in pts w/ activating mutations involving PRPP synthetase>
increased production/degradation of purines

Question 8

first line therapy for treating acute gouty arthritis

Answer 8

NSAIDS

Question 9

right knee pain and swellling caused by gout should be treated w/ a drug that targets what type of cells

Answer 9

NSAIDS> inhibit COX> exert braod anti-inflammatory effect> inhibits neutorphils

Question 10

acute gout drug taht inhibits neutrophil chemotaxisa nd phagocytosis by preventing microtuble formation

Answer 10

colchicine

Question 11

def of neutral aa trasnporters in proximal renal tubular cells and on enterocytes

Answer 11

Hartnup Disease (specifically TRYPTOPHAN)

Question 12

niacin def

Answer 12

loss of dietary tryptophan (Hartnups disease)

Question 13

ataxia
episodic erythematous and pruritis skin lesions
loose stools

Answer 13

niacin def

Question 14

inhibits initiation of protein synthesis by binding to and distoring structure of prokaryotic 30S ribosome

Answer 14

Streptomycin–STOPS initiation complex formation and causes misreading of MRNA by binding to the 30S subunit

gentamicin
neomycin
amikacin
tobramycin
streptomycin

Question 15

interfere w/ binding of aminoacyl tRNA to A site

Answer 15

Tetracyclines (tRNA site)

Question 16

elastin’s plasticity and ability to recoil is d/t

Answer 16

interchain crosslinking involving lysine

Question 17

contains unusual nucleosides like pseudouridine and thymidine

Answer 17

tRNA

Question 18

what sequence is at the 3’ end of tRNA and is used as a recognition sequence by proteins?

Answer 18

CCA

3’ hydroxyl group of the CCA tail is used as a binding site for the AA

Question 19

TATA box

Answer 19

upstream promoter region (TFs bind here to initate unwinding and separating of DNA)

Question 20

maturation process of precursor mRNA

Answer 20

addition of poly A tail at 3’ end
methylguanosine cap at 5’ end
removal of introns

Question 21

what happens if a tRNA is mischarged w/ the incorrect AA

Answer 21

incorporates WRONG AA into growing polypeptide chain (no proof reading during protein translation)

Question 22

maple syrup urine disease is caused by a def in what enzyme

Answer 22

alpha ketoacid DH

Question 23

what coenzymes does alpha ketoacid DH require?

Answer 23

Tender loving care for nancy

Thiamine (B1)
Lipoate
Coenzyme A
Fad
NAD

Question 24

what treatment can improve sxs of a pt w/ maple syrup urine disease

Answer 24

high dose thiamine

Question 25

folate def inhibits formation of dTMP, limiting DNA synthesis, promoting megaloblastosis and erythroid precursor cell apoptosis. what type of supplementation can REDUCE erythroid precursor cell apoptosis

Answer 25

thymidine increases dTMP levels

Question 26

rate limiting enzyme in the urea cycle

Answer 26

carbamoyl phosphate

Question 27

what actiavtes carbamoyl phosphate

Answer 27

NAG

Question 28

where do nitrogen atoms in the urea molecule come form?

Answer 28

NH3 | aspartate

Question 29

enz def in homocystinuria

Answer 29

cystathione synthase

Question 30

ectopia lentis (dislocated lens) intellectual disability marfanoid habitus High risk for tromboembolic episodes

Answer 30

Homocystinuria

Question 31

tx for cystathione synthase def

Answer 31

50% of pts respond to high doses of B6 if issue is w/ decreased affinity of CS for B6

Question 32

how is splenic hypertrophy related to pyruvate kinase def

Answer 32

PK def causes hemolytic anemia d/t failed glycolysis (not enough ATP to maintain RBC)> spleen must work harder to remove erythrocytes from circulation

Question 33

newborn w/ lethargy, vomiting, hypotonia Metabolic acidosis + hypoglycemia Increased concentration of propionic acid in urine

Answer 33

Proprionic acidimia caused by def in priopionyl CoA carboxylase Priopionyl Coa is derived from AA (val, ile, met, Thr), odd numbered FA and cholesterol side chains

Question 34

Lynche syndrome

Answer 34

AD abnormal nucleotide MMR (MSH2, MLH1)

Question 35

location of PPP

Answer 35

cytoplasm

Question 36

b oxidation, ketogenesis, citric acid cycle, parts of urea cycle, pyruvate carboxylation LCOATION?

Answer 36

mitochondria

Question 37

transketolase

Answer 37

enzyme of PPP that uses B1 as a cofactor

Question 38

pyruvate carboxylase

Answer 38

initial step in gluconeogenesis | converts pyruvate to OAA

Question 39

Ornithine transcarbamoylase

Answer 39

Ornithine and CP are combined to form citruline

Question 40

succinate dehydrogenase

Answer 40

enzyme of TCA converts succinate to fumarate

Question 41

HMG CoA lyase

Answer 41

mitochondrial enzyme responsible for ketogenesis from HMG CoA

Question 42

homeobox genes

Answer 42

DNA binding TF that play important role in morphogenesis

Question 43

hypoglycemia after prolonged fasting w/ LOW levels of ketone bodies

Answer 43

MCAD acyl CoA DH

Question 44

Hepatomegaly, cardiomegaly, macroglossia, hypotonia and mental retardation Polysaccharide accumulation in lysosomes

Answer 44

POMPE Disease alpha glucosidase def leads to glycogen accumulation in lysosomal vesicles responsible for breaking down small mats of glycogen

Question 45

severe neurologcial abnormalities d/t high blood and tissue ammonia levels + increased orotic acid excretion (d/t accumulated carbamoyl phosphate)

Answer 45

OTC def

Question 46

female w/ recurrent abdominal pain and anxiety that improves after IV heme preparation

Answer 46

increased gamma-ALA (causes sxs) and porphogiilinogen d/t over activation of ALA synthase ( usually inhibited by heme)