cell biology Flashcards
(97 cards)
1
Q
ionic bonds are also known as
A
electrostatic interactions
2
Q
because they depend on _____ on the R group, changes in ______ can disrupt ionic bonds
A
charge
pH
3
Q
redox aka
A
reduction-oxidation
4
Q
in redox reactions, what happens?
A
oxidation states of atoms are changed
5
Q
redox reactions are characterised by the actual or formal transfer of _______ between chemical species
A
electrons
6
Q
the reducing agent undergoes
A
oxidation
7
Q
the oxidising agent undergoes
A
reduction
8
Q
undergoing oxidation =
A
losing electrons
9
Q
undergoing reduction =
A
gaining electrons
10
Q
the reducing agent _______ electrons
A
loses
11
Q
the oxidising agent ________ electrons
A
gains
12
Q
the ______ agent loses electrons
A
reducing
13
Q
the _____ agent gains electrons
A
oxidising
14
Q
the chemical species from which the electron is removed is said to have been _______
A
oxidised
15
Q
the chemical species to which the electron is added is said to have been ______
A
reduced
16
Q
oxidation is the _____ of electrons or an _____ in oxidation state of an atom, ion, or certain atoms in a molecule
A
loss
increase
17
Q
reduction is the _____ of electrons or a ______ in oxidation state of an atom, ion, or certain atoms in a molecule
A
gain
decrease
a reduction in oxidation state
18
Q
compounds containing hydrogen which can be ionised to produce hydrogen ions (H+) when dissolved in water are named as ____ when_______
A
acids
when they are dissolved in water
19
Q
acids are
A
(aqueous-state) compounds which ionise in water to produce H+
20
Q
addition of x electrons
A
reduction
21
Q
[proteins’] primary structure
give basis of structure
A
AA sequence
22
Q
[proteins’] secondary structure
give basis of structure
A
folding into alpha helices, beta pleated sheets, or random coils
23
Q
[proteins’] tertiary structure
give basis of structure
A
3D folding
single polypeptide chain
24
Q
[proteins’] quaternary structure
give basis of structure
A
basis: association of multiple polypeptides to form a multimeric protein
25
[proteins'] primary structure
give kinds of bonds/interactions involved
covalent peptide bonds
26
[proteins'] secondary structure
give kinds of bonds/interactions involved
hydrogen bonds between NH (amino group) and CO (carboxyl group) groups of peptide bonds in the backbone
27
[proteins'] tertiary structure
give kinds of bonds/interactions involved (give 5)
```
disulphide bonds
hydrogen bonds
ionic bonds
van der Waals interactions
hydrophobic interactions
```
28
[proteins'] quaternary structure
give kinds of bonds/interactions involved (give 5)
```
disulphide bonds
hydrogen bonds
ionic bonds
van der Waals interactions
hydrophobic interactions
```
29
first law of thermodynamics =
law of conservation of energy
30
first law of thermodynamics states
energy is conserved
in every physical or chemical change, the total amount of energy in the universe remains constant
31
energy may be converted from one form to another but it cannot be created or destroyed.
which law said this
first law of thermodynamics
32
in every physical or chemical change, the total amt of energy in the universe ____________
remains constant
| 1st law thermodynamics
33
second law of thermodynamics states
reactions have directionality
34
favourable reactions are thermodynamically _________
spontaneous
| 2nd law thermodynamics
35
second law of thermodynamics =
thermodynamic spontaneity
36
thermodynamic spontaneity is a measure of whether or not a reaction or process ________________
can occur
37
reactions have directionality -- which law states this?
2nd law of thermodynamics
38
what does it mean that reactions have directionality
they can proceed spontaneously in ONLY ONE DIRECTION
| eg burning of a piece of paper -- can it un-burn itself? no
39
in every physical or chemical change, the universe tends towards ______________________
greater disorder or randomness (entropy)
40
universe tends towards entropy -- which law states this?
2nd law thermodynamics
41
define entropy
UNAVAILABILITY OF A SYSTEM'S THERMAL ENERGY FOR CONVERSION INTO MECHANICAL WORK
42
The zeroth law of thermodynamics defines thermal equilibrium and forms a basis for the definition of temperature:
If two systems are each in thermal equilibrium with a third system, then they are in thermal equilibrium with each other.
43
the first and second laws of thermodynamics prohibit
perpetual motion machines
44
first law of thermodynamics prohibits this type of perpetual motion machine:
produces work with no energy input
45
second law of thermodynamics prohibits this type of perpetual motion machine:
spontaneously converts thermal energy into mechanical work
46
second law of thermodynamics prohibits this type of perpetual motion machine:
spontaneously converts thermal energy into mechanical work
47
the second law of thermodynamics allows us to predict (2 things)
1. in which direction a reaction will proceed
(under certain conditions)
2. how much energy will be released
48
define eukaryote
having cell(s) with visible nucleus(i) surrounded by a nuclear membrane
49
name four common small molecules in a cell (say human)
amino acids
aromatic bases
sugars
lipids
50
aromatic bases are
5 or 6 carbon structures (aromatics)
| nucleobases
51
describe DNA or RNA in general terms (what are the two main structural components)
helix of sugar-phospates
| nucleobases (which form base pairs)
52
identify base pairs for DNA vs RNA
DNA - CG ; AT
| RNA - CG; AU
53
in RNA, uracil is traded for _______
thymine
54
name the five possible aromatic bases
```
adenine
cytosine
guanine
thymine
uracil
```
55
what's a nucleic acid
many nucleotides linked in a long chain
| e.g., DNA or RNA
56
how many amino acids do humans use
20
57
define essential amino acid
an amino acid that cannot be synthesized from scratch by the organism fast enough to supply its demand, and must therefore come from the diet
58
how many amino acids are essential to humans (and what does this basically mean)
nine
| basically humans can't synthesise
59
the nine amino acids humans cannot synthesize are:
phenylalanine, valine, threonine, tryptophan, methionine, leucine, isoleucine, lysine, and histidine.
60
what's the start codon?
AUG
| methionine also an acceptable answer
61
which amino acid is formed by the start codon?
methionine
62
what is a conditionally essential amino acid? (humans)
their synthesis can be limited under special pathophysiological conditions, such as prematurity in the infant or individuals in severe catabolic distress
63
what are the six conditionally essential AAs?
arginine, cysteine, glycine, glutamine, proline, and tyrosine.
64
what is the 21st AA?
selenocysteine
65
selenocysteine is an analogue of ______
| except in place of sulphur it has _____
cysteine
| selenium
66
throughout known life, there are ____ genetically encoded (proteinogenic) amino acids
22
67
which are used in (most) life, L-stereo-isomers, or D-stereo-isomers?
bonus: what's the exception
L-stereo-isomers
bacterial cell walls
68
L-stereo-isomers are
the left facing conformation
| R-group to the left of COOH
69
name five of the non-essential AAs
| 2 non-essentials are the 21st and 22nd AA
```
alanine
aspartic acid
asparagine
glutamic acid
serine
```
70
which three sugars are common in cells?
ribose
deoxyribose
glucose
71
what is the component of starch in glycogen?*
glucose
72
which two types of lipids are common in cells?
fatty acids
| cholesterol
73
fatty acids are components of (give two answers but they're really one)
phospholipids
| membranes
74
generally speaking, name the strongest and second strongest types of bonds which have attractions over greater distances
covalent -- strongest
| ionic -- second strongest (medium)
75
in 3d protein structure, name
a) a type of strong, covalent bond
b) a type of medium bond
c) a type of weak bond
d) 2 types of weak interaction
a) disulphide bonds
b) ionic :)
c) hydrogen bonds
d) van der Waals
hydrophobic interactions
76
enthalpy =
heat content
77
heat content can be expressed using the term _____
enthalpy
78
what are the components of the enthalpy expression (4)
(H) heat content
(E) internal energy
(P) pressure
(V) volume
79
express enthalpy
H = E + PV
80
catalysts work by
lowering activation energy
81
what is the result of adding a catalyst to reaction?
increases reaction rate
82
catalysts and substrates do what
form transient, reversible complexes together
83
catalysts change the _________ at which equilibrium is achieved, not the _________ of the equilibrium
catalysts change the rate at which equilibrium is achieved, not the position of the equilibrium
84
organic catalysts are called:
enzymes
85
Acids are:
compounds which release hydrogen ions (H+) when dissolved in water.
86
define polypeptide. give elemental basis for peptide bonding
a compound consisting of two or more amino acids linked in a chain, the carboxyl group of each acid being joined to the amino group of the next by a bond of the type −OC−NH−
87
components of plasma
```
water
antibodies
fat
electrolytes
clotting factors
glucose
proteins (albumins, globulins, fibrinogen)
hormones
co2
o2
```
NO:
WBCs are part of immune system and RBCs circulatory
88
extracellular matrix does three essential things
structural support -- protection, segregation, also cells bind to components of the ECM
keep liquid outside (px dessication and rupture)
communication between cells
89
______ make collagen
______ make bone
fibroblasts
osteoblasts
90
what kind of tissue is scar tissue
connective
91
basal lamina is _______ the basement membrane
a part of
92
diagram the body's fluids
intracellular fluid: 67%
extracellular fluid:
- interstitial: 26%
- intravascular: 7%
- CSF: <1%
93
diagram the body's fluids
intracellular fluid: 67%
extracellular fluid:
- interstitial: 26%
- intravascular: 7%
- CSF: <1%
94
what is the basal lamina?
part of ECM
secreted by epithelial cells
on which epithelial cells sit
electron-dense region
95
association of multiple polypeptides =
multimeric protein
96
define anabolism
the synthesis of complex molecules in living organisms from simpler ones together with the storage of energy; constructive metabolism.
late 19th century: from Greek anabolē ‘ascent’, from ana- ‘up’ + ballein ‘to throw’.
97
define catabolism
the breakdown of complex molecules in living organisms to form simpler ones, together with the release of energy; destructive metabolism.
late 19th century: from Greek katabolē ‘throwing down’, from kata- ‘down’ + ballein ‘to throw’.
