1
Q
Key elements present in living organisms as inorganic ions
A
Magnesium (Mg^2+) Iron (Fe^2+) Calcium (Ca^2+) Phosphate (PO4^3-) Nitrate (NO^3-)
2
Q
Magnesium
A
Constituent of chlorophyll (needed for photosynthesis)
3
Q
Iron
A
Constituent of haemoglobin (needed for O2 transport in blood)
4
Q
Calcium
A
Hardens bones and teeth
Component of plant cell walls
5
Q
Phosphate
A
Make nucleotides (ATP, RNA, DNA)
Constituent of phospholipids
Hardens bones
6
Q
Nitrate
A
Nitrogen from nitrate makes nucleotides (ATP, RNA, DNA)
Amino acid formation
7
Q
Water (polarity, H bonds, surface tension, solvent, thermal properties, metabolite)
A
- Dipolar molecule
- Hydrogen bonds between water molecules
- Water molecules join together to form skin of water at skin tension
- Water is a solvent for polar molecules like salts
- Water used for transport
- Water has a high latent heat of vaporisation (requires lots of heat to change state e.g. Perspiration)
- Water has a high specific heat capacity (requires a lot of energy to raise temperature) water is stable
- anomalous expansion of water (ice less dense than water)
- chemical reactions occur in water due to transport of ions and polar molecules when particles meet
8
Q
Water - What happens when sweating/perspiring?
A
Water has a high latent heat of vaporisation
Liquid water –energy–> water vapour
Requires a lot of energy to change state
9
Q
Respiration equation
A
Glucose + water ==> carbon dioxide + water
10
Q
Photosynthesis equation
A
Water + carbon dioxide ==> oxygen + glucose
13
Q
Elements in Lipids
A
Carbon, Hydrogen, Oxygen
13
Q
What happens in a condensation reaction?
A
Water is formed
14
Q
What happens in a hydrolysis reaction?
A
Water is used
15
Q
What is a condensation reaction?
A
Water is chemically removed to form a bond between adjacent monomers
16
Q
What is a hydrolysis reaction?
A
Water chemically added to break a bond between two monomers
17
Q
Elements in Phospholipids
A
Carbon, Hydrogen, Oxygen, Phosphorus
17
Q
Elements in Amino Acids and Proteins
A
Carbon, Hydrogen, Oxygen, Nitrogen, (Sulphur)
18
Q
Elements in Carbohydrates
A
Carbon, Hydrogen, Oxygen
19
Q
Elements in Nucleic Acids
A
Carbon, Hydrogen, Oxygen, Phosphorus, Nitrogen
20
Q
What are trioses?
A
3 Carbon sugars
20
Q
What are pentoses?
A
5 Carbon sugars
21
Q
What are hexoses?
A
6 Carbon sugars
23
Q
What is a polymer?
A
A large molecule comprising of repeated, identical units (monomers) bonded together
24
Q
Examples of carbohydrates
A
Glucose, fructose, sucrose, ribose, lactose, starch/amylose, glycogen
25
Monomer
Single unit sugar
26
Monosaccharides
1 sugar
27
Disaccharide
2 sugars
28
Polysaccharide
2+ sugars
29
Carbohydrates/monosaccharides rules
All Carbons in a straight line
One Carbon will have a =O bond
All other Carbons will have a -OH bond
Gaps filled with Hydrogens
30
Isomer
Same formula, different structure
31
3 types of monosaccharides
Trioses, Pentoses, Hexoses
32
Triose
C3H6O3
Important in metabolism
Intermediates of respiration and photosynthesis
33
Pentoses
C5H10O12
| Constituents of nucleotides (deoxyribose in DNA, ribose in RNA,ATP,ADP)
34
Hexose
C6H12O6
Source of energy in respiration (e.g. Glucose)
C-H and C-C bonds broken to release energy to make ATP
35
Monosaccharides that make Maltose
Glucose + Glucose
36
Monosaccharides that make Lactose
Glucose + Galactose
37
Monosaccharides that make Sucrose
Glucose + Fructose
38
Maltose
Sugar transported in seeds
| Used in beer
39
Lactose
```
Milk sugar (found in mammalian milk)
Transports energy from mother to baby
```
40
Sucrose
Transported in phloem of plants
| Product of photosynthesis
41
A hydrolysis reaction of Maltose plus water would make...
2 alpha glucose molecules
42
Monosaccharides used for...
Energy in respiration
| To build larger carbohydrates
43
Disaccharides used in...
Transport of energy
44
Polysaccharides used in...
Structural support or storage
45
Starch is made of..
Alpha glucose polymerised together (same way up)
2 polymers
Amylose, a component if starch (1,4 bonds) is a helix with smaller helixes off it called amylopectin (1,6 bonds) which is also a component of starch
[alpha-glucose units joined together + 2 polymers, amylose and amylopectin]
46
Starch allows...
Plants to store glucose
47
Amylose is..
A component of starch
48
Amylose made of...
Helix of starch, has chains of amylopectin
49
Glycogen is made of...
Alpha glucose with short 1,4 and many 1,6 bonds
| Has chains of amylopectin
50
Glycogen is...
The main storage product in animals
Found in liver (sometimes muscles)
Similar to starch but has more side chains for enzymes to attack and digest more quickly
51
Cellulose is..
Structural polysaccharide found in plant cell walls
| A polymer of Beta Glucose
52
Cellulose made of...
Beta glucose (1,4 bonds) where every other Beta glucose is rotated 180 degrees resulting in a straight chain microfibre
53
Chitin contains CHON so is a...
Polysaccharide derivative
54
Chitin is a...
Structural polysaccharide found in exoskeletons of insects and fungal cell walls
55
Chitin contains...
CHON
(O and N found in Amide)
Double Hydrogen bonds between Amides
56
Alpha glucose is when...
H is above C1
57
Beta glucose is when...
H is below C1
58
Starch is...
A large molecule (transport difficult)
Insoluble
Good for plants (stays put- plant can break down for growth and energy)
59
Test for starch
Add iodine to starch and solution will turn from orange/brown to blue/black
60
Test for reducing sugars and non reducing sugars
Add Benedict's solution to reducing sugar and heat to 80 degrees. Will turn from blue to red. If done to a non reducing sugar, negative result (stays blue). To achieve positive result, hydroxide with HCl acid then retest
61
Test for protein
Add Biuret solution to protein. Will turn from blue to lilac (purple)
62
Test for lipids (fats and oils)
Add ethanol to lipid (oil) then to water. Will turn from clear to cloudy (produces a white emulsion)
63
All fats are...
Lipids
64
Lipids contain...
CHO (mostly C and H, some O)
65
Fats and oils composed of...
Fatty acids and glycerol
66
Lipids broken down by...
Lipase
67
3 fatty acids plus 1 glycerol...
Triglyceride
68
What bond is in a triglyceride?
Ester bonds
69
What is an Ester bond?
O O
\ //
C
(C double bonded to O and bonded to another O)
70
Properties of lipids
- used as an energy reserve in plants and animals
- thermal insulator (stored under skin)
- protection (around organs)
- metabolic water source
- waterproof (insoluble- forms waxy cuticle)
- low density helps float
- nerve transmission
- steroids and cholesterol
- used in cell membrane formation (phospholipid bilayer)
71
Phospholipids contain...
CHOP
| Triglyceride with a fatty acid replaced with a phosphate group
72
Basis of cell membrane
Phospholipid bilayer
73
Unsaturated fats have...
At least one C=C bond
74
Unsaturated fats are...
Good for human health (found in plants)
75
Saturated fats are..
Bad for human health (found in meat)
76
Diet of saturated fats...
Low density lipoproteins (LDL) build up- increased risk of heart disease
77
Diet of unsaturated fats...
More High density lipoproteins (HDL)- higher HDL:LDL ratio decreases risk of heart disease
78
Amino acids contain...
CHON (S)
79
Basic structure of an amino acid...
Amino group
R group (variable side chain of CHON(S))
Hydrogen atom
Carboxyl group
80
How many amino acids are in living cells?
20 or 22
81
Simplest amino acids?
Glycine and Valine
81
What is a peptide bond?
O H
\\ /
C - N
(C double bond to O and bonded to a NH)
82
Product of amino acids reacting
Dipeptide
83
What are the levels of protein structure?
Primary
Secondary
Tertiary
Quaternary
84
What bond forms when Glycine and Valine react?
Peptide bond
85
What are classifications of proteins?
Globular and fibrous
85
What are globular proteins used for?
Enzymes, antibodies, hormones
86
What are fibrous proteins used for?
Keratin in hair
| Structural functions
87
Primary protein structure
Determined by DNA
Gives type, number and sequence of amino acids in polypeptide chain
One gene codes for one polypeptide
Peptide bonds between each amino acid
88
Bonds in primary protein
Peptide
89
Secondary structure in proteins
Shape after primary
Peptide and hydrogen bonds
Hydrogen bonds twist and folds polypeptide to form an alpha helix (or a beta pleated sheet)
90
Bonds in secondary protein
Peptide and hydrogen
91
Tertiary structure proteins
Shape after secondary
Alpha helix further folded and twisted to give a 3D structure
Peptide, hydrogen, disulphide, ionic (& covalent hydrophobic) bonds
Bonds maintain active site shape
92
Bonds in tertiary structure
Peptide, hydrogen, disulphide, ionic (& covalent hydrophobic) bonds
93
Enzymes have a _____ structure
Tertiary
94
Bonds in tertiary structure are to...
Maintain active site shape
95
Quaternary structure protein
Combination of 2 or more different polypeptide chains in tertiary structure
Associated with non protein groups and form large complex molecules (e.g haemoglobin)
96
Haemoglobin
4 polypeptide chains
4 genes needed to code for haemoglobin (each polypeptide molecule different)
Associated with non protein groups (haem group)
Quaternary protein structure
97
Collagen
3 polypeptide molecules
1 gene needed to code for collagen (each polypeptide molecule the same)
Not associated with non protein groups
Secondary protein structure
98
Globular proteins suited to function...
Compact, folded into 3D spherical molecules
| Soluble in water
99
Fibrous proteins suited to function...
Polypeptides in chains/sheets with cross linkages to form long fibres
Insoluble in water
100
Example of globular protein and its function
Haemoglobin - transports O2 to tissues
101
Example of fibrous protein and its function
Collagen - provided properties needed in tendons
