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Exam I

Chcm I53A. Winter 2010

1.    (3) Roughly how many protcins can lit insidc a human celi?

a.    1.000

b.    100.000

c.    I million (10⁶)

d.    I billion (10^V)

c. A googol (I0^1UO)

2.    (2) Givcn that the boiling point of water is I00°C and of mcthanol is 65°C:

Truć or false? Water bas a higher boiling point than mcthanol bccausc its hydrogen bonds arc slrongcr.

3.    (3) In the cquation for the diclcctric constant. K is the forcc of intcraction bctwccn:

a.    Two ions

b.    Two water moleeules

c.    Solvcnt and solutc

d.    Nonę of the abovc

4.    (3) Which of the following is most important in stabilizing the structurc of integral membrano protcins?

a.    hydrogen bonds

b.    the hydrophobic cffcct

c.    van der Waals contacts

d.    ion pairs

e.    disulftde bonds

5.    (4) Which of the following arc rcasons why mass spcctromctry is a uscful tool in protein scqucncing? (Choosc all that apply.)

a.    Scqucncc idcntification can be automated

b.    It is possiblc to identify modifleations to amino acids

c.    A pcptidc's scqucncc can be unambiguously determined

d.    Mass spcctromctric sequcncing is faster than Edman scqucncing c. The masses of all amino acids arc uniquc

6.    (3) Complctc the sentence to dcfinc ‘osmosis* as it relates to biochcmistry; add 15 words or fcwcr.

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