Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

biology a level OCR > biological molecules (carbohydrates, lipids and proteins) > Flashcards

biological molecules (carbohydrates, lipids and proteins) Flashcards

1
Q

monomer

A

a small molecule that binds to many other identical molecules to from a polymer

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

polymer

A

a large molecule made up of many monomers bonded together

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

covalent bond

A

a strong bond formed when electrons are shared between 2 atoms

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

condensation reaction

A
  • 2 hydroxyl groups, line up alongside each other
  • 1 combines with an H atom to form on H2O
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

hydrolysis reaction

A
  • a water molecule, is used to split the disaccharide
  • breaks the glycosidic bond
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what elements do all biological molecules contain

A

carbon, hydrogen and oxygen

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

name a non - reducing sugars

A

sucrose

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

name 3 reducing sugars

A
  • lactose
  • maltose
  • cellubiose
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

name 3 reducing sugars

A
  • lactose
  • maltose
  • cellobiose
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what is a qualitative test

A

positive or negative results (tells use whether a particular substance is present)

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

what is a quantitative test

A

tells us how much (concentration) of a substance is present)

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

are polysaccharides more or less soluble in water than monosaccharides

A

less soluble in water

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

what is the structure of amylose?

A
  • straight chain structure
  • alpha - glucose molecules held together by 1,4 glycosidic bonds
  • repetition of 1,4 glycosidic bonds, causes amylose to coil into a helix
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what is the structure of amylopectin?

A
  • similar to amylose, but can also from 1,6 glycosidic bonds
  • forms branches, that allows amylase (enzyme) to break of molecules of glucose when the are require
  • (they do contain 1,4 glycosidic bonds as well as the 1,6)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what is the structure of cellulose

A
  • each adjacent beta - glucose molecule, will rotate 180 degrees in order to from the straight chain.
  • this allows it to from a straight chain glycosidic bond
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what is the most common type of lipids

A

triglycerides

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

what are the two main properties of lipids

A
  • insoluble in water (non - polar)
  • high in energy -> rich in C-H bonds ( higher than carbohydrates)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what is a condensation reaction

A

occur when 2 molecules, are joined with the removal of water -> forms a covalent bond

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

what is a hydrolysis reaction

A

splitting, 2 molecules apart with the addition of water -> breaks a covalent bond

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

what is the monomer of carbohydrates

A

monosaccharides

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

what is the polymer of carbohydrates

A

polysaccharides

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

what is the monomer of proteins

A

amino acids

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

what is the polymer of proteins

A

polypeptide

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

what is the definition of a polar molecule

A

a molecule with regions of slight positive charge and slight negative charge.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
what will happen if something is less dense than water for example a frog
it will simply float on the surface of the water.
26
what bonds do amino acids form, when the interact with the water,
hydrogen bond
27
why must lipids not be filtered, with filter paper, when doing a food test
the lipids, could stick to the filter paper
28
what is a reducing sugar
reducing sugars, can donate an electron to another molecule
29
what are the properties that water has, due to hydrogen bonds?
- liquid at room temperature - density - solvent for molecules - water and non polar molecules - cohesion and surface tension - high specific capacity - high latent heat of vaporisation - water as reactant (not directly linked to hydrogen bonds)
30
what are the properties, of monosaccharides
- sweet taste - soluble in water (polar solvent) - insoluble in non - polar solvents
31
what are isomers
molecules, with the same molecular formula, but a different structural formula.
32
what is the structure of Alpha - Glucose
33
what is the structure of Beta - Glucose
34
what are the properties of disaccharides
- taste sweet - soluble in polar solvents - some are reducing (donate electrons)
35
give an example of a reducing sugar and an example of a non - reducing sugar
- maltose (reducing) - sucrose (non - reducing)
36
what is a reducing agent
- donates/provides electrons to another molecule
37
what is a oxidising agent
accepts electrons from another molecule
38
oxidation is … reduction is …
- loss of electrons - gain of electrons
39
all monosaccharides are reducing sugars
true
40
what is a polysaccharide
a molecule, which consists of hundreds or thousands of monosaccharides, which are joined by condensation reactions, resulting in the formation of glycosidic bonds
41
why are glycogen and amylopectin branched
- more compact - also offers the chance, for lots of glucose molecules to be snipped off by hydrolysis at the same time, when lots of energy is required.
42
describe, what happens in the formation of Starch
- amylose helix, becomes tangled in amylopectin branches - mixtures of amylose/amylopectin build up
43
describe the structure of Glycogen
- very similar to amylopectin, but it is more branched (more frequent 1,6 glycosidic bonds) - more compact - insulin, causes alpha glucose molecules, to condense
44
what are the properties of lipids
- insoluble in water (non - polar) - but are soluble in organic solvent e.g. - ethanol - high in energy (higher than carbohydrates)
45
what is a unsaturated fatty acid
- this means that there is one or more carbon double bond - this causes the molecule to kink, thus spacing it out more.
46
what is a saturated fatty acid
- only contains single carbon bonds
47
what is the structure of a triglyceride
- a glycerol backbone, connect to 3 fatty acid molecules, via 3 carbon bonds.
48
how do the fatty acid molecules, attach to triglyceride
- they attach via a condensation reaction
49
what do we call the bond that is formed between each fatty acid and hydroxyl group
- an ester bond
50
what are the functions of triglycerides
- energy source - energy store - insulation (heat insulator or electrical insulator - buoyancy - protection
51
what are waxes composed of
- waxes are composed of large alcohols, attached to fatty acids
52
how do we test for lipids
- the emulsion test - add the mixture, to ethanol shape and see if a emulsion layer (precipitate) has formed, to signify the presence of a lipid
53
what are phospholipids
they are like a triglyceride, except one of the fatty acids is replaced by a phosphate group.
54
what is cholesterol
- cholesterol, is a steroid alcohol - consists of 4 carbon based rings or isoprene units - in animals, it is made in the liver
55
what are the properties and functions of cholesterol
- helps to regulate the fluidity of the cell membrane - at high temperatures, it stabilises the membrane and raises the melting point. - at low temperatures it intercalates between the phospholipids and prevents clustering
56
what are the functions of proteins
- essential component of phospholipid bilayer - all enzymes are proteins - antibodies are proteins - haemoglobin - collagen - keratin - structural role
57
what is the structure of an amino acid
58
what is primary protein structure
sequence of amino acids, held together by peptide bonds
59
what is the secondary protein structure
folding of amino acid chain into alpha helix or beta pleated sheet, due to hydrogen bonding between amino acids.
60
what is the tertiary protein structure
folding of the secondary structure, to form a precise 3D shape.
61
what is the quaternary protein structure
a protein, which is made up of 2 or more polypeptide chains.
62
what are the 5 Cations
- calcium - sodium - potassium - hydrogen - ammonium
63
what are the 5 Anions
- nitrate - hydrogen carbonate - chloride - phosphate - hydroxide
64
how do you test for non reducing sugar?
- carry out a normal sugar test and get a negative result - take some of this sample, and boil it with hydrochloric acid (use anti bumping granules) - cool the solution and then add sodium carbonate to neutralise the solution, - check using pH paper that the solution has been neutralised. - then carry out the reducing sugar test again and you should have positive result in the form of a brick red precipitate if non - reducing sugars are present.
65
why do we use anti bumping granules in the non reducing sugar test?
To prevent the formation of large gas bubbles that cause violent boiling.
66
why do we filter the red precipitate after the benedicts test
in order to form a supernatant solution, that we can use in order to measure the light absorbance on a colorimeter and we can compare this to known values, in order to see the concentration of the solution.
67

biology a level OCR (32 decks)

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