1 - Biological Molecules Flashcards
1
Q
Why is water polar?
A
Oxygen is ẟ negative and hydrogen is ẟ positive
2
Q
Bond that attracts water molecules to eachother
A
Hydrogen
3
Q
Give 5 properties of water
A
High SHC Less dense as solid Cohesion - surface tension Adhesion Universal solvent
4
Q
How to test for reducing sugars
A
Equal volume of Benedict’s and heat
+ = blue to red
5
Q
How to test for reducing sugars
A
Boil with HCL and add Benedict’s
+ = blue to red
6
Q
Test for starch
A
Add a few drops of iodine
+ = orange to black
7
Q
Test for proteins
A
Equal volume of Biuret A and B
+ = blue to violet
8
Q
Test for lipids
A
Add alcohol and water, shake
+ = white emulsion forms on top
9
Q
Define macronutrient
A
Nutrients that are needed in large amounts and provide body with energy
10
Q
4 examples of macronutrients
A
Carbohydrates
Lipids
Proteins
Water (but no calories)
11
Q
Define micronutrients
A
Nutrients that are needed in small amounts and important for normal functioning of the body
12
Q
4 examples of micronutrients
A
Hydrogen ions (pH) Iron ions (haemoglobin) Sodium ions (AA, CNS) Phosphate ions (DNA and ATP
13
Q
Define organic
A
Contains carbon
14
Q
Name the monomer of carbohydrates
A
Glucose
15
Q
Name the di-saccharides of carbohydrates
A
Sucrose, maltose
16
Q
Name the polysaccharides of carbohydrates
A
Starch, cellulose, glycogen
17
Q
Name 3 monosaccharides
A
Glucose, fructose, galactose
18
Q
Two types of glucose
A
Alpha and Beta
19
Q
Alpha Beta glucose difference
A
Alpha - H Beta - OH
OH H
20
Q
Bond in fructose
A
Carbon 2 and Carbon 5
21
Q
Name 3 disaccharides
A
Maltose, sucrose, lactose
22
Q
……………+……………= maltose
A
Alpha glucose + alpha glucose
23
Q
……………+……………= sucorse
A
Alpha glucose + beta fructose
24
Q
……………+……………= galactose
A
Alpha glucose + galactose
25
What bond connects two glucose in maltose
| -----------o---------------
Alpha 1-4 glyosidic bond
26
What reaction bonds the glucose together
Condensation
27
Opposite of condensation reaction
Hydrolysis
28
What is also formed in a condensation reaction
Water
29
What is starch made of?
Amylose and amylopectin
30
What is starch
Energy store in plants
31
Why does iodine test for starch?
Iodine gets trapped in helix of amylose
32
What is amylopectin? Bond?
Polymer of alpha glucose
| Alpha 1-6 glyosidic bond
33
What feature does amylopectin have?
Side branches
34
What is glycogen?
Immediate energy store in animals
35
Bond in glycogen
Alpha 1-4 and Alpha 1-6 glyosidic bond
36
Adaptation of glycogen
Big SA so release glucose from every branch by breaking it
37
What is cellulose of polymer of?
Beta glucose
38
Bond in cellulose
Beta 1-4 glyosidic bond
39
Why is the structure of cellulose weird?
Every second glucose flips 180o to form parallel chains
40
Three uses for lipids
Insulation, waterproof, protection
41
3 differences between fats and oils
Fats - animals, solid, saturated
| Oils - plants, liquid, unsaturated
42
Is C=C saturated or unsaturated?
Unsaturated
43
Is c-c-c-c-c- saturated or unsaturated?
Saturated
44
What are lipids made of?
Glycerol and fatty acids
45
Draw glycerol
H H H
H-C-C-C-H
H H H
O O O
46
Draw a fatty acid
H H H H
O= C - C - C - C - C -H
OH H H H H
47
Three groups in a fatty acid
Carboxyl (COOH)
Methyl (CH3)
Hydro-carbon chain
48
Bond in a triglyceride that connects glycerol to fatty acid?
Ester
49
Difference between triglyceride and phospholipids?
In a phospholipid, one of the FA is replaced by a phosphate group
50
What is in a phospholipid?
| Polar?
```
Phosphate head (polar)
Glycerol
2 FA (non-polar)
```
51
How many different AA are there?
20
52
Draw a amino acid?
R
COOH - C - NH2
H
53
3 groups in an amino acid
```
Carboxyl group (COOH)
R group
Amino group (NH2)
```
54
4 different types of r group
Acidic
Basic
Polar
Neutral
55
What is a dipeptide
Two AA bonded together
56
Bond in a dipeptide
Peptide
57
Name the 5 structures a protein can be in
Primary, secondary, tertiary, quaternary, conjugated
58
Describe the primary structure
1° - order and number of amino acids in a polypeptide chain. DNA sets this order
59
Bonds in primary structure
Peptide
60
Describe the secondary structure
Alpha helix and beta pleated sheets
| Two primary together
61
Bonds in secondary structure
Hydrogen and peptide
62
Describe the tertiary structure
Globular shape and bonding between r groups
| Determine overall shape
63
Bonds in tertiary structure
Hydrophobic interactions - non-polar r groups
Hydrogen bonds - r group
Ionic bonds - acidic and basic r groups
Disulphide ridges - sulphide r group (covalent bonds)
64
Describe the quaternary structure
More than one polypeptide chain. E.g. haemoglobin
65
Bonds in quaternary structure (4 and where found)
Hydrophobic interactions - non-polar r groups
Hydrogen bonds - r group
Ionic bonds - acidic and basic r groups
Disulphide ridges - sulphide r group (covalent bonds)
66
Describe the conjugated structure
A non-protein molecule is attached and is inorganic
67
Define enzyme
A biological catalyst that lowers the activation energy of a reaction
68
Describe induced fit
Substrate enters active site forming an enzyme-substrate complex (not complementary)
Active site changes shape which puts pressure on bonds in substrate
Lower activation energy
69
5 things that impact rate of enzyme catalysed reactions
```
Temperature
pH
Enzyme concentration
Substrate concentration
Inhibitors
```
70
Name the 2 types of inhibitor
Competitive and non-competitive
71
How does temperature impact the rate of an enzyme catalysed reaction
More kinetic energy = more collisions =more ES complexes = higher rate
Pass optimum temp then denature (hydrogen bonds break = lose tertiary structure = no complementary )
/\
/ \
/ \
/ \
72
How does pH impact the rate of an enzyme catalysed reaction
```
Move away from optimum pH (Hydrogen concentration changes) so ionic bonds break so active site isn't complementary so no ES complex
/\
/ \
/ \
/ \
```
73
How does enzyme concentration impact the rate of an enzyme catalysed reaction
Directly proportional to rate
/
/
/
74
How does substrate concentration impact the rate of an enzyme catalysed reaction
```
Enzyme becomes limiting factor
x2 conc. = x2 rate
All active sites are occupied so enzyme is saturated
_____________________
/
/
```
75
How do competitive inhibitors impact the rate of an enzyme catalysed reaction
Molecule with similar shape to substrate binds to active site
Low sub con. = low rate
Will reach maximum rate
76
How do non-competitive inhibitors impact the rate of an enzyme catalysed reaction
Attaches to enzyme (not AS)
Changes bonding and AS so not complementary to substrate
Doesn't reach maximum rate
77
Give 5 characteristics of Globular proteins
```
Transport (hormones)
Lightly folded pp chains
Soluble
Haemoglobin
Compact and spherical
```
78
Give the two types of proteins
Globular and Fibrous
79
Give 5 characteristics of Fibrous proteins
```
Structural and strength
Parallel pp chains
Long and narrow
Insoluble in water
Collagen
```
80
Describe haemoglobin (3)
Globular protein
4pp chains
2 alpha helixes and 2 beta pleated sheets
81
Describe collagen
Fibrous protein
| 3 pp chains and unbranched
82
What does ATP stand for?
Adenosine triphosphate
83
Describe structure of ATP
3 phosphate circles
Ribose pentagon
Rectangle nitrogenous base (Adenine)
84
What does ATP turn into to release energy?
| Full name
ADP (Adenosine diphosphate) and Pi (inorganic phosphate)
85
4 uses of ATP
Active transport
CNS
Muscle contraction
Protein synthesis
86
1 glucose molecule = ….. mole of ATP
38
87
Explain how cellulose molecules are adapted for their function in plant cells (3)
1. Long and straight chains;
2. Become linked together by many hydrogen bonds to form fibrils;
3. Provide strength (to cell wall);
88
Difference between glycogen and starch
Starch - energy source in plants
| Glycogen - energy source in animals
