Bio mols (1) Flashcards
1
Q
What is a monomer
A
Smaller units which can create larger molecules
2
Q
What is a polymer
A
Made from lots of monomers bonded together
3
Q
Name 3 examples of monomers
A
- Glucose
- Amino acids
- Nucleotide
4
Q
Name 6 examples of polymers
A
- Starch
- Cellulose
- Glycogen
- Protein
- DNA
- RNA
5
Q
What reaction joins monomers to form polymers
A
Condensation reaction
6
Q
What is a condensation reaction
A
Joining 2 molecules creating a chemical bond and removing 1 water molecule
7
Q
What reaction breaks down polymers into monomers
A
Hydrolysis reaction
8
Q
What is a hydrolysis reaction
A
Breaks the chemical bond between 2 molecules through the addition of 1 water molecule
9
Q
Name 3 monosaccharides
A
- Glucose
- Fructose
- Galactose
10
Q
Name 3 disaccharides
A
- Sucrose
- Maltose
- Lactose
11
Q
Name 3 polysaccharides
A
- Starch
- Cellulose
- Glycogen
12
Q
Chemical formula for glucose
A
C6H12O6
13
Q
What is alpha glucose’s relation to beta glucose
A
Isomers
14
Q
Where is the OH group in alpha glucose
A
On the bottom
15
Q
Where is the OH group in beta glucose
A
On the top
16
Q
What bond forms when disaccharides are formed
A
Glycosidic bond
17
Q
Glucose+Glucose=
A
Maltose+water
18
Q
Glucose+Galactose=
A
Lactose+water
19
Q
Glucose+Fructose=
A
Sucrose+water
20
Q
Where are Starch and Cellulose found
A
Plants
21
Q
Where is glycogen found
A
Animals
22
Q
Monomers of starch and glycogen
A
Alpha glucose
23
Q
Monomers of cellulose
A
Beta glucose
24
Q
Bonds in amylose (starch)
A
1-4 glycosidic
25
Bonds in amylopectin (starch)
1-4 and 1-6 glycosidic
26
Bonds in cellulose
1-4 glycosidic
27
Bonds in glycogen
Lots of 1-6
Some 1-4
28
Function of starch
Store of glucose
29
Function of cellulose
Structural support (cell wall)
30
Function of glycogen
Store of glucose
31
Structure of amylose and amylopectin
Amylose=unbranched helix
Amylopectin=branched molecule
32
Structure of cellulose (3)
Long straight polymer chains, held in parallel by H-bonds, forming fibrils
33
Structure of glycogen
Highly branched
34
What is the purpose of the helix structure of amylose
Compact, lots fit in a small space
35
What is the purpose of glycogen and amylopectin being branched
Increased surface area, results in rapid hydrolysis and release of glucose
36
What is the purpose of the large number of H-bonds in cellulose
They provide collective strength (important for cell wall)
37
What do starch, cellulose, and glycogen all have in common
All large and insoluble, meaning water potential isn't affected
38
What does a triglyceride consist of
1 Glycerol
3 fatty acids
39
What does a phospholipid consist of
1 Glycerol
2 Fatty acids
1 phosphate group
40
Are triglycerides and phospholipds polymers
No
41
What bonds are formed in the formation of triglycerides and phospholipds
Ester bonds
42
How do triglycerides form the bonds
OH on fatty acid and H on glycerol join, producing the necessary water molecule
43
What is a saturated fatty acid
Fatty acid with no carbon double bonds
44
What is an unsaturated fatty acid
Fatty acid with at least 1 double carbon bond
45
Why is it useful for triglycerides to be low mass
Lots stored without increasing mass too much
46
Why is it useful for triglycerides to be large and hydrophobic
Doesn't affect osmosis or water potential
47
How are triglycerides a metabolic water source
Large ratio of H:O atoms, release water if oxidised
48
How are triglycerides good for energy storage
Large ratio of high energy C-H bonds: Carbon atoms
49
Name 4 features of triglycerides
1. Good for energy storage
2. Metabolic water source
3. Large and hydrophobic (doesn't affect water potential or osmosis)
4. Low mass
50
How many condensation reactions occur when a phospholipid is formed
2
51
What properties does the phosphate head have on a phospholipid
Negative charge, therefore attracts water and repels lipids (hydrophillic)
52
What is the formation of phospholipids in the phospholipid bilayer
Tails face eachother
Heads on outside facing water
53
What monomer makes proteins
Amino acids
54
What 5 groups are present in an amino acid
1. Central carbon atom (C)
2. Singular Hydrogen atom (H)
3. Carboxyll group (O and OH), (O is double bonded to central carbon atom)
4. R group (varies between every aminon acid
5. Amino group (NH2)
55
What bond is formed through the formation of a dipeptide or polypeptide
Peptide bond
56
When is the primary structure of a protein determined
Straight after translation
57
What is the primary structure of a protein
The order/sequence of amino acids in a polypeptide chain
58
What happens in the secondary structure of a protein (2)
Either:
1. Bending of polypeptide chain into alpha helix
2. Folding of polypeptide chain into beta pleated sheet
59
How is the secondary structure of a protein held together
By H bonds
60
What happens in the tertiary structure of a protein
Further folding into a unique 3d structure
61
What determines the bonds in the tertiary structure
The order of amino acids (primary structure)
62
What bonds hold the tertiary structure together (3)
1. H bonds
2. disuphide bridges
3. ionic bonds
63
What makes a protein have a quaternary structure instead of a tertiary structure
If there is more than one polypeptide chain
64
What protein structure is an enzyme
Tertiary
65
What is an enzyme
A biological catalyst that lowers the activation energy needed for a reaction
66
How many reactions can an enzyme catalyse
Only one
67
What determines the shape of the active site of an enzyme
Primary protein structure (sequence of amino acids)
68
What is the accepted model of enzyme action
Induced fit
69
What is the induced fit model (3)
1. Active site changes shape slightly to mould around the substrate
2. This puts strain on the bonds
3. Meaning less energy is required to break these bonds
70
Name 5 factors that affecting the rate of enzyme action
1. Temperature
2. PH
3. Enzyme concentration
4. Substrate concentration
5. Inhibitors
71
What happens to enzyme action when temp is too low
1. Less KE, slower speed
2. Less frequent collisions
3. Less ESCs formed
72
What happens to enzyme action when temp is too high
1. Bonds within active site break
2. Causes enzyme to change shape and denature
3. No ESCs can form
73
Either side of optimum PH, is denaturing rapid or slow
Rapid
74
Why does PH affect enzyme action
1. Interferes with charges of amino acids in active site
2. This breaks the bonds
3. Causing the active site to change shape
75
What happens to enzyme action when there isn't enough substrate
1. Less frequent collisions
2. Less ESCs formed
76
What happens to enzyme action when there isn't enough enzyme
1. All active sites are saturated
2. Rate of reaction doesn't change
77
Where does a competitive inhibitor bind
Enzyme's active site
78
Where does a non-competitive inhibitor bind
Enzyme's allosteric site
79
What happens if enough substrate is added in the presence of a competitive inhibitor
The substrate knocks out the inhibitor, allowing ESCs to form again
80
How can a competitive inhibitor bind to the active site of an enzyme
It's the same shape as the substrate
81
What do non-competitive inhibitors do
1. Bind to allosteric site
2. This changes the shape of the active site
3. No ESCs can form
82
How to test for starch
1. Add iodine
2. Positive test=orange goes blue/black
83
How to test for reducing sugars
1. Add Benedicts reagent
2. Heat it
3. Positive test =blue goes red
4. If low level of reducing sugars, blue goes green
84
Test for non reducing sugars
1. Following Benedict's test
2. Add acid and boil
3. Cool solution and add alkali
4. Add Benedicts and reheat
5. Positive=blue goes orange/red
85
Test for proteins
1. Add biuret
2. Positive=blue goes purple
86
Test for lipids
1. Dissolve in ethanol (and shake)
2. Add distilled water
3. Positive=white emulsion
87
What does DNA do (2)
1. Codes for amino acids in primary protein structure
2. Contains all of the genetic code
88
What is the monomer of DNA
Nucleotides
89
What does a single nucleotide contain
1. Phosphate group
2. Deoxyribose (5C) sugar
3. Nitrogenous base
90
What are the 4 nitrogenous bases found in DNA
1. Adenine
2. Thymine
3. Cytosine
4. Guanine
91
What bonds connect nucleotides in a DNA strand
Phosphodiester bond
92
Property of sugar phosphate backbone and why
Very strong due to the strong covalent phosphodiester bond
93
What bonds the nitrogenous bases in the double helix
H bonds
94
What is rRNA used for
rRNA and proteins make up ribosomes
95
4 key differences between DNA and RNA
1. RNA is shorter (mRNA is the copy of only one gene whilst DNA is the entire genetic code)
2. Uracil used instead of thymine
3. Ribose sugar instead of deoxyribose sugar
4. RNA is single stranded
96
RNA function
Transferring the genetic code from the nucleus to the ribosome
97
How does DNA replicate
Semi-conservative replication
98
What is semi-conservative replication
One original DNA strand combines with one newly synthesised strand
99
4 steps of semi-conservative replication
1. DNA helicase breaks H bonds between base pairs
2. Free floating nucleotides align with complementary bases
3. DNA polymerase joins adjacent nucleotides together through phosphodiester bonds
4. New molecule of DNA=daughter DNA
100
Who discovered the structure of DNA
Watson and Crick
101
Who proved semi-conservative replication
Meselson and Stahl
102
What does ATP consist of
Adenine base, ribose sugar, 3 phosphate ions
103
What is the function of ATP
Immediate source of energy in biological processes
104
When is ATP made
During respiration when ATP synthase joins ADP+Pi together
105
How does ATP release energy
When ATP hydrolase hydrolyses one of the phosphate bonds
106
What is phosphorylation
After ATP is hyrolysed, the Pi joins to a different compound, making it more reactive
107
What are the 5 key properties of water
1. It is a metabolite
2. It is a good solvent
3. It has a high specific heat capacity
4. It has a high latent heat of vaporisation
5. It has strong cohesion between molecules
108
Why is water a good solvent
It is dipolar (oxygen slightly negative and hydrogen slightly positive)
109
Why is it good for water to have a high specific heat capacity
Takes lots of energy to raise the temperature of water, meaning it is at a constant temp most of the time
110
Why is it good for water to have a high latent heat of vaporisation
Provides a cooling effect as lots of energy is required to evaporate water, so the heat energy is converted into energy to evaporate water
111
Why does water have good cohesion between molecules
Due to the H-bonds that form between molecules
112
What do hydrogen ions do (2)
1. Lower PH
2. Used in chemiosmosis
113
What do iron ions do
Involved in haemoglobin and therefore the transport of oxygen
114
What do sodium ions do (2)
1. Help transport glucose and amino acids in absorption
2. Involved in action potentials
115
What do phosphate ions do (2)
1. Help form the phosphodiester bonds in DNA and RNA
2. Used in phosphorylation
