Module 3 - Biological Molecules Flashcards
(112 cards)
1
Q
What are carbohydrates made up of
A
carbon, oxygen, hydrogen
2
Q
What are lipids made up of
A
carbon, hydrogen, oxygen
3
Q
What are proteins made up of
A
carbon, hydrogen, oxygen, nitrogen, phosphorus
4
Q
What are polar molecules
A
molecules with regions of negativity and regions of positivity
5
Q
What are hydroxyl groups
A
organic molecules that contain oxygen and hydrogen. They are slightly polar
6
Q
Is water a polar molecule
A
yes
7
Q
Does water have a high boiling point
A
yes
8
Q
Water has cohesive properties - what does this mean?
A
it moves as one mass because the molecules are attracted to each other (this is cohesion)
9
Q
Water has adhesive properties - what does this mean?
A
water molecules are attracted to other materials
10
Q
Why is water important for life?
A
water acts as a solvent where many solutes in organisms can dissolve, it is a coolant, habitat and transport medium
11
Q
name 4 solutes
A
polar molecules, amino acids, proteins, nucleic acids
12
Q
Water is an efficient transport medium
A
especially in plants (cohesion)
13
Q
the effects of adhesion and cohesion result in water exhibiting what?
A
capillary action - water can rise up a narrow tube against the force of gravity
14
Q
Water acts as a coolant - what does this mean?
A
it buffers temperature changes during chemical reactions, maintains temp in cellular environments
15
Q
Carbohydrates are also known as what?
A
saccharides or sugars
16
Q
what is a single sugar unit known as?
A
a monosaccharide
17
Q
name 3 examples of monosaccharides
A
glucose, fructose, ribose
18
Q
when two monosaccharides join what do they form
A
a disaccharide
19
Q
name 2 examples of a disaccharide
A
lactose, sucrose
20
Q
when two or more monosaccharides are linked they form what type of polymer?
A
a polysaccharide
21
Q
give 3 examples of a polysaccharide
A
glycogen, cellulose, starch
22
Q
what is the chemical formula of glucose
A
C6H12O6
23
Q
what type of sugar is glucose?
A
a hexose monosaccharide (hexose sugar)
24
Q
what does alpha glucose look like?
A
H at the top, OH at the bottom. CH20H in the top left, O in the top right
25
what does beta glucose look like?
OH at the top, H at the bottom. CH2OH in the top left, O in the top right
26
what is the name of the covalent bond that forms between two glucose molecules?
glycosidic bond
27
what type of reaction creates a glycosidic bond? why?
a condensation reaction - because a water molecule is formed as one of the products
28
what type of sugars are fructose and galactose?
hexose monosaccharides
29
glucose + glucose =
maltose
30
fructose + glucose =
sucrose
31
galactose + glucose =
lactose
32
what are pentose monosaccharides
sugars that contain 5 carbon atoms
33
name 2 pentose monosaccharides
ribose, deoxyribose
34
many alpha molecules joined by glycosidic bonds form what?
starch
35
name one polysaccharide found in starch
amylose
36
how is amylose formed
1-4 glycosidic bonds of alpha glucose
37
three properties of amylose:
twists to form a helix with H bonds, compact, less soluble
38
how is amylopectin formed
1-4, 1-6 glycosidic bonds of alpha glucose
39
what type of structure does amylopectin have
branched structure
40
what is the energy storage molecule for starch in animals and fungi?
glycogen
41
two properties of glycogen:
more branches than amylopectin, more compact - less space needed for it to be stored
42
why is branching for glycogen and amylopectin good?
there are many free ends for glucose molecules to be added or removed. makes storing and releasing glucose faster
43
why is branching for glycogen and amylopectin good?
there are many free ends for glucose molecules to be added or removed. makes storing and releasing glucose faster
44
what type of reaction does glucose undergo to be used for respiration?
hydrolysis reaction - addition of water molecules
45
what is the only way that beta glucose molecules can join?
one has to be flipped upside down
46
what is formed through the joining of beta glucose molecules?
a straight chain molecule called cellulose
47
are lipids polar or non-polar?
non-polar
48
are lipids soluble in water?
no
49
how are triglycerides made?
1 glycerol + 3 fatty acids
50
what is the name of the group of molecules that fatty acids belong to?
carboxylic acids
51
what do carboxylic acids consist of?
a carboxyl group (-COOH) and a hydrocarbon chain
52
what are ester bonds and how do they form?
they are three water molecules and bonds between the fatty acids and the glycerol molecule. Esterification
53
what type of reaction is esterification?
a condensation reaction
54
what is the feature of a saturated fatty acid chain?
no double carbon bonds
55
what is the feature of an unsaturated fatty acid chain?
double bonds between some carbon atoms
56
what does the presence of double bonds cause?
causes the molecule to kink or bend
57
what are phospholipids?
modified triglycerides
58
what 4 elements do phospholipids contain?
phosphorus, carbon, hydrogen, oxygen
59
are tails hydrophobic or hydrophilic?
hydrophobic
60
are heads hydrophobic or hydrophilic?
hydrophilic
61
what are the roles of lipids?
membrane formation, hormone production, electrical insulation (myelin sheath), waterproofing e.g. bird wings, cushioning for vital organs
62
what test is used to identify lipids?
emulsion test
63
how is an emulsion test conducted?
sample mixed with ethanol > mixed with water + shaken > if white emulsion forms on top, lipids are present
64
what bonds are formed when amino acids are made?
peptide bonds
65
what is formed when many amino acids joined by peptide bonds join together?
a polypeptide
66
what are the 4 types of protein structures?
primary, secondary, tertiary, quaternary
67
what is primary structure?
sequence of amino acids. determines the function of an AA, decides how it is folded
68
what is secondary structure?
hydrogen bonds form in the chain, coil shape formed called alpha helix
69
what is tertiary structure?
includes sections of secondary structure, folding brings R-groups of different amino acids closer
70
what is quaternary structure?
van der Waals bonds between subunits. interactions are the same as tertiary, but they are between difference protein molecules
71
what type of reaction breaks down peptides?
hydrolysis reaction - it reforms the amine and carboxylic acid groups
72
name 3 features of globular proteins
compact, water soluble, spherical shape
73
how are globular proteins formed?
when proteins fold into tertiary structure
74
name 3 examples of globular proteins
insulin, conjugated proteins, haemoglobin
75
what are conjugated proteins?
globular proteins that contain a non-protein prosthetic group
76
name an example of a prosthetic group:
haem groups (contain iron 11 ion/Fe2+)
77
what structure does haemoglobin have?
quaternary structure, two alpha and two beta subunits. Haem group has an affinity for oxygen
78
how are fibrous proteins formed?
formed from long, insoluble molecules
79
name 3 examples of fibrous proteins:
keratin, elastin, collagen
80
what is the function of keratin
strength and support for hair, skin and nails. forms disulphide bonds/bridges
81
what is the function of elastin
found in elastic fibres - give flexibility to walls of blood vessels and alveoli
82
what is the function of collagen
connective tissue found in skin, tendons, ligaments, nervous system. flexible, long and strong
83
what are the two types of nucleic acid
DNA and RNA
84
what is a nucleic acid made up of?
pentose sugar, phosphate group (negatively charged acidic inorganic molecule --> -PO42-), nitrogenous base
85
what does DNA stand for?
deoxyribonucleic acid
86
what are pyrimidines?
smaller bases, single carbon ring structures
87
what are purines?
larger bases, double carbon ring structures
88
what bases are pyrimidines?
thymine, cytosine
89
what bases are purines
adenine, guanine
90
what is the role of RNA?
transferring of genetic information from DNA to proteins that make up enzymes and tissues
91
what does RNA stand for?
ribonucleic acid
92
what is the structure of RNA?
ribose (pentose sugar), thymine replaced with uracil (pyrimidine), phosphate group
93
what does uracil bond with?
adenine
94
how do RNA nucleotides form polymers?
the formation of phosphodiester bonds in condensation reactions (same as DNA)
95
what does DNA polymerase do in semi-conservative replication?
catalyses the formation of phosphodiester bonds between nucleotides
96
what does genetic code mean?
the coding of a sequence of amino acids
97
what is a triplet code?
a sequence of three bases, known as a codon
98
what does each codon code for?
an amino acid
99
what is a gene?
a section of DNA that codes for a protein/amino acid
100
what is degenerate code?
an amino acid that can be coded for by more than one codon
101
what is transcription?
base sequences of genes are copied and transported to a ribosome
102
what does transcription produce
shorter molecules of RNA
103
what is the function of mRNA?
mRNA binds to specific site on ribosome. mRNA is decoded/translated into a sequence of amino acids
104
what is tRNA and what is it necessary for?
another form of RNA, needed for the translation of mRNA
105
what 3 types of activity do cells require energy for?
synthesis for proteins, transport of molecules/ions, movement for muscle contraction
106
what does ATP stand for?
adenosine triphosphate
107
what is ATP composed of?
nitrogenous base, pentose sugar, 3 phosphate groups
108
how does ATP release energy?
weak bond broken holding the last phosphate group
109
what is the equation for a hydrolysis reaction involving ATP?
ATP + H2O --> ADP + Pi + energy
110
what does ADP stand for?
adenosine diphosphate
111
what is Pi?
inorganic phosphate
112
what are the properties of ATP?
small - easily moves in and out of cells
water soluble
contains bonds between phosphates with intermediate energy
releases energy in small quantities - stops wasting of energy
easily regenerated - can be recharged with energy
