Biological molecules Flashcards
1
Q
What is the general formula for carbohydrates?
A
Cn H2n On
2
Q
What are the functions of carbohydrates?
A
- Source of energy
- Store of energy
- Structural units
3
Q
What is the monomer of carbohydrates
A
monosaccharides
4
Q
What is the polymer of carbohydrates
A
polysaccharides
5
Q
What is the molecular formula of glucose
A
C6 H12 O6
6
Q
is glucose a monosaccharide
A
yes
7
Q
properties of the glucose monosaccharide
A
- Good source of energy because they have a high number of C-H bonds which can be used to release energy in respiration
- Also due to OH groups its soluble in polar solvents e.g water and insoluble in non polar solvents
8
Q
Give an example of isomers of glucose
A
Alpha and beta glucose
9
Q
what is the difference between alpha and beta glucose?
A
Alpha - H and OH on carbon 1 and 2 are pointing in the same direction
Beta - H and OH on carbon 1 and 2 pointing in opposite directions
10
Q
Give an example of a pentose sugar
A
Ribose
11
Q
Give an example of a hexose sugar
A
glucose
12
Q
Explain the condensation of two glucose monosaccharides (forming a disaccharide)
A
The OH of each monosaccharide disappears and an O bond forms between the two joining them together (C-O-C) + H2O
13
Q
What is the name of the (O) bond that forms between monosaccharides
A
Glycosidic bond
14
Q
What is the process of splitting a disaccharide into two monosaccharides?
A
Hydrolysis - water is added which breaks the glycosidic bond
15
Q
alpha glucose + alpha glucose =?
A
Maltose
16
Q
alpha glucose + fructose =?
A
Sucrose
17
Q
Beta galactose + alpha glucose =?
A
lactose
18
Q
give 2 examples of reducing sugars
A
maltose and lactose
19
Q
give an example of a non reducing sugar
A
sucrose
20
Q
What is the equation for respiration
A
glucose + oxygen = carbon dioxide + water (+energy)
21
Q
Where is starch found animal or plants
A
in plants
22
Q
What is starch made of and which type of glucose
A
amylose and amylopectin
alpha glucose
23
Q
Which isomer of glucose is amylose made of and what type of glycosidic bond does it have (1-4 or 1-6)
A
alpha glucose 1-4
24
Q
What does 1-4 glycosidic bond mean?
A
Which carbon the glycosidic bond is formed, carbon 1 and 4
25
Is amylose coiled or not coiled if so why is it helpful
coiled - makes it more compact which is good for storage.
26
Is amylose soluble or insoluble and why?
insoluble - OH groups facing on the inside of the coiled amylose, hiding the hydrophillic surfaces on the inside of the molecule
27
What type of glycosidic bonding does amylopectin contain
both 1-4 and 1-6
28
How does 1-6 glycosidic bonds cause branching
Because the glycosidic bond is at carbon 1 and carbon 6 so the alpha glucose being bonded at carbon 6 has to be tilted slightly so that the bond can form. The bonding is at a different angle compared to 1-4 which is straight
29
Where is glycogen found animals or plants
in animals
30
What type of glycosidic bonding does glycogen contain
both 1-4 and 1-6
31
What is the structural difference between amylopectin and glycogen
glycogen has shorter sections of coiling / branches and it has more 1-6 bonds increasing how compact it is
32
What makes starch and glycogen so suited to storage?
- compact
| - easy access (through branching) more branches = more points of access to enzymes = quicker hydrolysis of monomers
33
Which enzyme hydrolyses alpha 1-4 glycosidic bonds
amylase
34
Which enzyme hydrolyses alpha 1-6 glcosidic bonds?
glucosidase
35
compare solubility of glycogen and starch
less water soluble than individual monomers of glucose so water potential of the cells that store them aren't disrupted, WP wont decrease and rate of metabolic reactions not affected
36
Describe cellulose
tough
insoluble
fibrous
component of plant cell wall
37
Does cellulose contain alpha or beta glucose?
beta glucose
38
What type of glycosidic bond does cellulose contain
beta 1-4 glycosidic bonds
39
What must happen to beta glucose in order for a glycosidic bond to form between them by condensation
one must be inverted because beta glucose has the H and OH flipped around so the 2 OH groups on each glucose arent next to each other. so water cant form and the (O) glycosidic bond cant form
40
Is beta 1-4 glyocosidic bond coiled
No it is straight
41
What is formed when 60-70 beta glucose chains are bound together
microfibril
42
What does lots of microfibrils make
macrofibrils
43
What makes cellulose suited to it being structural/ in cell walls
has high tensile strength of micro and macro fibrils difficult to rip apart - strength comes from H bonds and covalent glycosidic bonds
Macrofibrils arranged in criss cross direction = extra strength
difficult to digest
44
What is the bacterial cell wall made of
peptidoglycan
45
What are exoskeletons of insects and crustaceans made of
chitin
46
Are lipids soluble in water and why
insoluble as they are non polar molecules
47
are lipids soluble in alcohol
yes as alcohol is less polar
48
3 types of lipids
triglycerides
cholesterol
phospholipid
49
Are lipids polymers
no as theyre not made of repeating monomers they are macromolecules (made of different components)
50
What are triglycerides made of
glycerol and 3 fatty acids
51
What is the structure of trglycerides
glycerol - chain of carbons with H and OH attached
| Fatty acid COOH (carboxyl) and chain of carbons with H attached
52
What is a saturated hydrocarbon chain
No C-C double bonds
53
What is a unsaturated hydrocabon chain
has C-C double bonds
54
What does more unsaturated fatty acids/hydrocarbon chains mean
Closer to being a liquid as its more fluid and has a lower melting point.
55
What is the bond that holds the glycerol and fatty acids together to make a triglyceride?
Ester bond (C-O-C=O )
56
Which process forms an ester bond
esterification/condensation
57
Functions of triglycerides
Energy source - by hydrolysis of ester bonds
Energy store - as they're insoluble, doesnt affect WP of cells releases more energy than sugar.
good insulator
mechanical protection e.g around the heart
buoyancy -helps animals float
waterproofing - hydrophobic & insoluble
58
Structure of phospholipid
Phosphate head
| 2 fatty acid chains one saturated and one unsaturated
59
How are phospholipids amphipathic
hydrophilic portion and hydrophobic portion forms phspholipid BI-layer
forms micelles
60
Structure of cholesterol
4 isoprene units + hydrocarbon chains, non polar
61
function of cholesterol
regulates fluidity of bilayer
| makes hormones like testosterone oestrogen and vitamin D in animals
62
What are amino acids and how many are found in proteins of humans
basic building blocks of proteins
| 20 found in humans
63
structure of amino acid
NH2 - CHR-COOH amino group, R group and carboxyl group
64
What do lots of amino acids make
Polypeptides/proteins
65
How are amino acids joined together forming peptide bonds
By condensation O=C-N
66
How are peptide bonds broken
hydrolysis
67
What is the primary structure of protein
sequence of amino acids
68
What is the secondary structure of protein
coiling or folding of amino acid chain - beta pleated sheet, alpha helix, unstructured region, each held by H bonds so its easily affected by pH and temperature
69
What is the tertiary structure of proteins
folding of alpha helix, beta pleated sheets and unstructured regions forming a 3D shape
70
What types of bonding occurs in tertiary structure
ionic bonding , oppositely charged ions
H bonding - bewteen O-H/ O-N
disulphide bridge - S-S
Hydrohphobic and hydrophillic interactions - uncharhed or polar areas possibly OH group or ring of carbon
71
What is the quaternary structure
lots of polypeptide chains to make a protein
72
What is a fibrous protein structure?
extended, regular and repetitive primary structure, simple secondary structure,
73
What is globular protein structure?
round, compact, irregular primary structure, complex secondary structure
74
functions/properties of fibrous proteins
Structural role, insoluble, less sensitive to pH and temp changes
75
functions/properties of globular proteins
metabolic roles, soluble, more sensitive to pH and temp changes
76
What type of protein is collagen
fibrous
77
function of collagen
```
provides mechanical strength
in arteries - prevents it from bursting
tendons- connect muscle to bone so we cant lift heavy stuff/ withstand large forces
bones
cartilage
```
78
What type of protein is keratin
fibrous
79
function of keratin
```
mechanical strength for
hair
nails
claws
hoofs
horns
scales
fur
```
80
What type of protein is elastin
fibrous
81
Give an example of a globular protein
haemoglobin
82
structure of haemoglobin
2 alpha and 2 beta chains.
| Haem groups containing Fe ions it is a conjugated protein
83
What is a haem group
type of prosthetic group (essential to function of protein)
84
function of haemoglobin
carry oxygen from lungs to tissue changes oxygen from dark red/purple to bright red
85
What is computer modelling used for
predicting the tertiary structure of protein by ab initio or comparative protein modelling
86
Does insulin contain alpha helix or beta pleated sheet
both
87
What is the role of insulin
Regulate glucose concentration in the blood
88
How does insulin fulfil its role/what does it do?
It binds to a specific target receptor which triggers the uptake of glucose into cells and the metabolism of glucose in respiration. This decreases the glucose concentration in the blood
89
How does insulin fulfil its role/what does it do?
It binds to a specific target receptor which triggers the uptake of glucose into cells and the metabolism of glucose in respiration. This decreases the glucose concentration in the blood
90
Is calcium a cation or anion
cation
91
role of calcium
increases rigidity of bone teeth cartilage and exoskeletons.
involved in blood clotting and stimulation of muscle contraction and controlling nerve impulses responsible for muscle contraction
importnat for regulating membrane permeability
and cell wall development in plants
92
is sodium a cation or anion
cation
93
role of sodium
regulates osmotic pressure helping regulate water levels in body fluids and maintaining pH
Also important part of vacuoles involved in turgidity in plant cells
important for absorption of carbs in intestine and water in kidney
Also involved in nervous transmission
94
Role of potassium
synthesis of glycogen and protein
break down of glucose
generating healthy flowers and leaves in plants
involved in active transport in cell membranes
