Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Alevel Biology > Biological Molecules > Flashcards

Biological Molecules Flashcards

1
Q

What do carbohydrates and lipids contain?

A

Carbon, hydrogen and oxygen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are proteins made of?

A

Carbon, hydrogen, oxygen, nitrogen, sometimes sulphur

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are nucleic acids made of?

A

Carbon, hydrogen, oxygen, nitrogen and phosphorus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are macromolecules?

A

Biological molecules that contain a very large number of atoms. Many of these are polymers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Monomer and polymer of carbohydrates?

A

Monomers: monosaccharides
Polymers:polysaccharides

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Monomer and polymer of proteins?

A

Monomer: amino acids
Polymers: polypeptides

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Monomer and polymer of nucleic acids?

A

Monomers: nucleotides
Polymer: polynucleotides

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Monomer and polymer of lipids?

A

They are macromolecules not polymers.
Made of base units joined together in a non-repeating pattern
Glycerol +3 fatty acids= triglyceride

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How are polymers formed from monomers?

A

By condensation reactions, molecule of water formed in process, grouped hydroxyl and hydrogen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is hydrolysis?

A

Breaking polymer into individual monomers, require water to break bond

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Condensation vs hydrolysis?

A

Condensation: monomers joined together, forms water, forms bonds
Hydrolysis: monomers broken apart, requires water, breaks bonds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are proteins?

A

Chains of amino acids that form a polypeptide
They contain carbon, hydrogen, oxygen, nitrogen and sometimes sulphur
They are in enzymes, muscles, blood, hair, skin, bone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Examples of proteins?

A

Amylase, hormones, collagen, melanin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is a dimer?

A

Two monomers bound together

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is a polymer?

A

3 or more monomers bound together

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What happens when peptide bonds
Form between amino acids toform a dipeptide?

A

1.) amino acids join in a condensation reaction
2) hydrogen bonds together
3.) a water molecule is left

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are globular proteins?

A

Soluble and spherical shape, soluble due to presence of charged r groupwater molecules can surround the protein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are fibrous proteins?

A

Straight chain polypeptides,side by side held in place by hydrogen bonding, insoluble, lots of disulphide bridges so they are more resistant to physical and chemical attack

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What are primary protein structures?

A

Sequence chains of amino acids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is a secondary protein structure?

A

Hydrogen bonding of of the peptide backbone, causes amino acid to fold in repeating pattern

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is a tertiary protein structure?

A

Three-dimensional folding pattern of a protein due to side chain interactions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is a quaternary protein structure?

A

Protein consisting of more than one amino acid chain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is glucoses structure?

A

6 carrion atoms, sugars with 6 carbon atoms, heroes sugars, its a single sugar molecule

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What are key properties of monosaccharides?

A

Soluble in water
Hydrophilic
Can be joined chemically to form larger carbs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What’s the difference between alpha and beta glucose?
Betas OH is above the ring and alphas is below
26
How do you break a glycosidic bond?
Add water to break bond, converts it back to original monosaccharides (hydrolysis)
27
How do you make Sucrose?
Glucose + fructose
28
How do you make lactose?
Glucose and galactose
29
What is amylose structure?
Unbranched alpha glucose in a larger number in a helix shape with hydrogen bonds between glucose molecules
30
Structure of amylopectin?
Branched chains every 25-30 glucose molecules of alpha glucose , joined by glycosidic bonds
31
Structure of glycogen?
Very compact polymer of alpha glucose which is branched
32
Why do enzymes convert glycogen back to glucose so quickly?
High volumes of free ends
33
Structure of cellulose?
Polymer of beta glucose Every 2nd beta glucose molecule flips Unbranched polysaccharide Straight chains
34
What’s the function of cellulose?
Hydrogen bonds form between chains making them very strong (microfibrils) which can join together to make cellulose fibre (cell wall), important for stopping cell wall bursting
35
What can lipids be used for?
Waterproofing, major structure of membrane, energy source
36
what are triglycerides made up of?
A glycerol and 3 fatty acids
37
What are phospholipids made of?
Phosphate + glycerol + 2 fatty acids
38
What do phospholipids form?
Bilayers (membrane)
39
What happens when lipase breaks the ester bond due to hydrolysis?
Glycerol and fatty acid molecules are released
40
Points of the induced fit model?
Enzymes catalyse reaction by lowering activation energy Bind to a substrate to form enzyme substrate complex Shape of active site isn’t exactly complimentary to the substrate so slightly changes
41
How does temperature denaturing occur?
Tertiary structure is held by weak bonds, if enough weak bonds are broken by heating the tertiary structure unravels this causes active sites shape to be lost and the enzyme denatures
42
What are 2 conditions that denature an enzyme?
Too high temperature Too low/high pH
43
What is the test for starch?
Add iodine Orange to blue/black is a positive test
44
Test for reducing sugars?
Benedict’s reagent and het Blue to green, yellow,orange or brick red is positive
45
Test for non-reducing sugars?
Following negative Benedict’s test add acid and boil (hydrolysis), cool the solution and add an alkali to neutralise, add Benedict’s reagent and heat, positive test- blue to green,yellow,orange brick red
46
Test for proteins?
Add burnet Blue to purple- positive
47
Test for lipids?
Dissolve lipid in ethanol, add distilled water, positive = white emulsion forms
48
Examples of reducing sugars and what they can do to copper sulphate?
Glucose, fructose, galactose, lactose, maltose Copper sulphate (blue) is reduced in Benedict’s reagent to copper oxide (brick red)
49
Example of non-reducing sugar and what it does to copper sulphate?
Sucrose Can’t reduce copper sulphate as the reducing group is used up by the glycosidic bond Hydrolyse sucrose (boil in acid then add an alkali to neutralise, this breaks the glycosidic bond and then add Benedict’s so it turns brick red
50
How are polysaccharides formed?
When more than two monosaccharides join together by condensation reaction
51
What is starch?
Mixture of 2 polysaccharides of alpha glucose, amylose + amylopectin
52
What is DNA?
Store of generic information
53
What is RNA (ribonuclease acid) role?
Transfers genetic information from DNA to ribosomes (protein factories), read the RNA and make polypeptides in translation
54
What is a nucleotide made of?
Penrose sugar (sugar with 5 atoms) Nitrogen-containing organic base Phosphate group
55
What is the Penrose sugar in a DNA nucleotide called?
Deoxyribose
56
What are the 4 possible bases for nucleotides?
Adenine (A), thymine (T), cytosine (C), guanine (G)
57
What does an RNA nucleotide consist of?
Phosphate group and one of four different bases
58
What replaces thymine as a base in RNA?
Uracil
59
What is a monomer?
Smaller units which are the components of larger molecules
60
What are disaccharides?
Two monosaccharides joined together in a condensation reaction
61
Features of glycogen that makes it useful?
Larger number of side branches (energy can be released quickly), relatively large but compact, maximising the amount of energy it can store, Insoluble so it doesn’t effect water potential of cells
62
Test for reducing and non reducing sugars?
Reducing: add the food sample in a liquid form Add 2cm of Benedict’s reagent Heat the mixture in a water bath for 5 mins, if solution turns brick red, orange/brown then reducing sugar is present NON REDUCING: if solution is still blue add dilute hydrochloride acid so It can hydrolyse Add sodium hydrogencarbonate to neutralise test Ph paper used to check Now add 2cm of Benedict’s reagent to solution and place in water bath If non reducing sugar is present brick red will be observed
63
Where are saturated lipids found?
Animal fats, don’t contain any carboncarbon double bond
64
Where are unsaturated lipids found?
In plants, they contain carboncarbon double bond
65
Triglycerides structure related to their properties?
High ratio of energy storing carbon-hydrogen bonds to carbon so they are excellent energy store Low mass to energy ratio, less mass to move around Release water when they are oxidised so good for organisms in dry environments
66
How to do the emulsion test for proteins?
1.)Take a grease free test tube and add 2cm of sample and 5cm of ethanol 2.) shake the test tube to dissolve all lipids 3.) add 5cm of water and shake 4.) cloudy-white colour indicated the presence of a lipid 5.) as control, repeat experiment using water as the sample
67
Features of disulphide bridges?
Interactions between soulful in r group of amino acid cysteine, STRONG AND NOT EASILY BROKEN
68
Features of Ionic bonds?
Form between the carbonyl and amino groups not involved in peptide bond, EASILY BROKEN BY PH AND ARE WEAKER THAN DISULFIDE BRIDGES
69
Features of hydrogen bonds?
Numerous and easily broke
70
How to carry out burnet test for proteins?
1.)Place sample in test tube with equal volume of sodium hydroxide at room temp 2.) add very dilute copper sulphate solution and mix 3.) a purple colour indicates presence of protein, negative would remain blue
71
How does temperature affect the rate of enzyme-controlled reaction?
Rate of reaction increases up to optimum, kinetic energy increases, above optimum rate of reaction decreases as enzymes denature
72
How does PH affect the rate of enzyme-controlled reactions?
Affects enzymes shape so disrupts the bond in tertiary structure
73
How does enzyme concentration affect the rate of enzyme controlled reactions?
As enzyme concentration increases rate of reaction increases, more active sites for substrates to bind to, beyond a certain point there is no change, there are more active sites than substrates so concentration becomes limiting factor
74
How does substrate concentration affect the rate of enzyme controlled reactions?
Rate of reaction increases as more enzyme-substrate complexes are formed, beyond a certain point the rate of reaction no longer increases as enzyme concentration becomes the limiting factor
75
How does concentration of competitive reversible inhibitors?
As competitive reversible inhibitors increases, rate of reaction decreases as the active site are temporarily blocked by inhibitors so substrates cannot bind to them
76
How does the concentration of non-competitive reversible inhibitors?
As concentration on non-competitive reversible inhibitors increases, rate of reaction decreases as the shape of enzyme is altered by the inhibitors
77
Different between DNA and RNA chains?
DNA is a double helix of 2 polynucleotides joined by hydrogen where as RNA is a relatively short polynucleotide chain
78
What are the 3 steps of semi-conservative replication of DNA?
1.) enzyme, DNA helicase, causing the two strands of DNA to separate breaking the hydrogen bonds between the complementary bases 2.) one of the strands is used as the template and complementary base pairing occurs between the templates strand and free nucleotides 3.) once activated nucleotides are bound the enzyme DNA polymerase joins them together by forming phosphodiester bonds, 2 identical strands of DNA formed.

Alevel Biology (3 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions