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Flashcards in Basic Concepts Deck (46):
1

True or false?
water is dipole

true

2

Describe how water has a partial positive and negative charge

oxygen (an electronegative atom) pulls the electrons from H, resulting in a partial positive charge

oxygen's unpaired electrons result in a partial negative charge

3

the dipole characteristic of water allows ___ bonds to form

hydrogen

4

True or false?
Hydrogen bonding in water imparts its relatively low viscosity, surface tension, and boiling point

false; high

5

Hydrogen bonding between water and polar groups of bio-molecules allows water to be an excellent ___

solvent

6

Hydrogen bonding also occurs between various ___ groups of bio-molecules

polar

7

1 dl = ___ ml

100

8

50 g/L = ___ g/dl

5

9

Equivalent units are used for ions and are based on what?

available charges of the ion

10

For singly charged ions, one mole = ___ equivalent

one

11

For doubly charged ions, one mole = ___ equivalents

two ex: [Mg+2]

12

True or false?
pH can affect enzyme activity

true

13

Define osmolarity

the total number of solute particles in a solution

14

1M NaCL solution is ___ Osmolar

2

15

True or false?
Osmolality is the number of osmoles/kg solution

true

16

Osmotic pressure causes movement of H2O from ___ solution to ___ solution

dilute; concentration

17

True or false?
Cell membranes are impermeable to H2O

false; permeable

18

Define tonicity

relationship between two solutions separated by permeable membrane

19

Two solutions with equal osmolarities are considered ___

isotonic

20

A solution (A) with a greater osmolarity than another (B) is ___ with respect to B

hypertonic

21

H2O will move from a ___ solution to a ___ solution

hypotonic; hypertonic

22

What happens to cells bathed in a hypotonic solution?

they swell

hint: O in hypotonic looks like swollen cell

23

What happens to cells bathed in a hypertonic solution?

they shrink, as they become dehydrated

24

Hypertonic serum may also cause cellular dehydration which is thought to play a role in the CNS problems associated with what?

DKA

note: ions are too concentrated in the cell; the cells need water

25

A bronsted-lowry acid does what?

can donate an H+

26

A bronsted-lowry base does what?

can accept an H+

27

True or false?
strong acids only partially dissociate

false; completely dissociate

28

What is the normal blood pH range?

7.35-7.45

29

What does a large Ka mean in regards to dissociation

Larger Ka means more dissociation

30

Ka is a measure of the ___ of the weak acid

"strength"

31

A larger Ka is a ___ acid

stronger

32

A smaller Ka is a ___ acid

weaker

33

HA -> H+ A-
adding OH- will do what to this rxn?

decrease the [H+], driving net rxn to the right

34

Define a buffer system

a system that will resist large changes in pH from strong acids or bases

35

HA -> H+ A-
A- is the ____ ___ of HA

conjugate base

36

a buffer system has its best buffering capacity when pH = ?

pKa

37

At the greatest buffering capacity, relatively large amounts of base are required for relatively small changes in pH. true or false?

true

38

A buffering region on a titration curve, gives you a clue about the AA. Alanine has 2 buffering regions, therefore, has ___ titratable weak acid groups

2

39

CO2 + H2O -> H2CO3 -> HCO3- + H+
what enzyme reverses this reaction?

carbonic anhydrase

40

Bicarbonate is transported in the ___ to the ____

blood; lungs

41

CO2 + H2O -> H2CO3 -> HCO3- + H+
Carbon dioxide is expelled from the lungs, shifting the net reaction to the ___

left

42

What is the henderson hasselbach equation?

pH = pKa + log {A-}/{HA}

43

Keq = Ka = ?

[H+][A-}/[HA]

44

pH = ?

-log[H+]

45

DKA results in an excess of organic acids called ___ ___

ketone bodies

46

The "___" respirations are an attempt to decrease the [CO2] in the patient

kussmaul