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Flashcards in Week 5 Deck (211)
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1

Pyrimidine pathway begins with what?

glutamine, CO2, 2 ATP

2

Describe what occurs in Complex III

contains cavern, electrons picked up by cytochrome C and taken to IV, pumps 4 protons to intermembrane space

3

Cytochromes contain _____ cofactors that can be reduced or oxidized

heme

4

How is the X chromosome inactivated?

packaged into transcriptionally inactive heterochromatin. Heterochromatin coats inactive X DNA and prevents its transcriptional expression --> forms Barr body. Xist gene encodes RNA responsible for mediating this silencing.

5

When non-equal concentrations are known, which equation should be used for delta G?

Delta G = Delta G naught + RTln[y]/[x]

6

Purine biosynthesis starts with what molecule?

ribose-5-P

7

Describe the enrgy required to convert oxaloacetate to citrate

-9 kcal/mol

8

In sperm, all imprints are erased and rewritten with _______ pattern; in eggs, rewritten with _______ pattern; even in genes that come from opposite sex parent

paternal, maternal

9

Describe how acetylcholine promotes the synthesis of NO

Acetylcholine binds to GPCR on endothelial cell --> IP3 generated --> increases Ca++ --> activates NO synthase --> NO produced from arginine

10

Isocitrate to alpha-ketoglutarate to succinyl coA - both steps are promoted by this cofactor

Calcium

11

What is the wobble base on tRNA?

3rd position in codon not totally required to match by all tRNAs (sometimes you get an I matching)

12

In Huntington's Disease, there is greater expansion in _______ parent transmission than in ______

male, female (gametogenesis)

13

_________ genes are susceptibility targets for numerous human pathologies such as Angelman and Prader WIlli Syndrome

imprinted genes

14

A positive feedback mechanism that results in ______________ would be an NZ that is activated by a signaling molecule but is then further stimulated by products that bind back to the NZ/signal complex and further stimulate it.

switchlike behavior

15

Nucleoside monophosphate kinases convert ATP and NDP to

ADP and NDP

16

What are the three tissues most dependent on oxidative phosphorylation?

heart, skeletal muscle, central nervous system

17

TCA cycle enzymes are found in what part of the mitochondria?

Matrix

18

Describe how the COX2 pathway can result in neoplasia (4 factors)

promotes tumor angiogenesis, induces tumor cell growth, inhibits apoptosis, dec immunosurveillance

19

Describe the four step process of tRNA binding

1) aminoacyl tRNA binds to vacant "A" site
2) a new peptide bond is formed at "P" site
3) mRNA moves 3 nucleotide positions through ribosomal subunit to E site
4) spent tRNA is ejected and the ribosome is reset

20

When a hormone secreted from a cell travels through the blood stream and binds to receptor on target cell, what signaling system is occurring? (encounter lots of cells during travel)

endocrine

21

Describe the age and conflict of the child in the oral stage.

birth-1 yr, primary conflict - weaning, fixation can lead to excess reliance and vulnerability to overconsumption of food or alcohol. Frustrations can lead to pessimism, envy and aggression.

22

__________ is usually the first AUG from 5' cap site

kozak sequence

23

During pyrimidine synthesis, _____ is added halfway through the cycle to produce orotidine (OMP)

PRPP, catalyzed by orotic acid transferase

24

DNA methyltransferases can be indirectly repressed by _________

mir-29b

25

Modified ________ ensure that a differentiated cell stays differentiated

histones

26

Describe how NO causes rapid relaxation of smooth muscle cell

NO binds to guanylyl cyclase and converts GTP to cyclic GMP which causes rapid relaxation

27

How do ROCK and PKC activation inhibit MLCP activity?

ROCK phosphorylates MYPt1 inhibitory protein and PKC phosphorylates CPI-17 inhibitory protein, which leads to inactivation of MLCP

28

How do macrolides (such as erythromycin) inhibit protein synthesis?

prevent the Movement of ribosomes(translocation)

29

Non-specific NSAIDS also block the inducible COX2 pathway. Normally, the COX2 pathway can lead to ________ and _______ via PGE2. Why are these dangerous?

inflammation, neoplasia
causes ulcers

30

How is phosphate transported to the matrix to provide substrate for ATP synthase?

Through the phosphate translocase (symporter), moves protons and phosphate in