Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Year 12 Biology (module 2) > Biological Molecules > Flashcards

Biological Molecules Flashcards

1
Q

What makes water a polar molecule? (structure)

A
  • One oxygen Atom (O) join with two Hydrogen atoms (H2) by shared electrons.
  • Shared hydrogen electrons are pulled towards the oxygen atom meaning the other side of each hydrogen atom is left with a slight positive charge.
  • The unshared negative electrons on the oxygen atom give it a slight negative charge.
  • This makes water a polar molecule.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Properties of Water (5)

A
  • High specific heat capacity.
  • High latent hear of evaporation.
  • Cohesive.
  • Good solvent.
  • Less dense when solid.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

High specific heat capacity

A
  • Hydrogen bonds between water molecules can absorb a lot of energy.
  • Meaning it takes a lot of energy too heat up (high specific heat capacity).
  • Means water doesn’t experience rapid temperature changes, making it a good habitat.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

High Latent Heat Of Evaporation.

A
  • It takes a lot of energy (heat) to break the hydrogen bonds between water molecules.
  • This means a lot of energy is used up when water evaporates.
  • Means water is a good coolant. (This is why some mammals sweat).
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Cohesive

A
  • Water is very cohesive (meaning they stick together) because they’re polar.
  • Makes it easier for water to flow.
  • Means water is good for transporting substances and helps water transport up plant stems in the transpiration stream.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Good Solvent

A
  • Water’s polarity will mean ions dissolve in water.

- Important ions can dissolve in the water in blood and then be transported around the body.

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

Less dense when solid.

A
  • Water molecules are held further apart in ice (less dense).
  • Therefore, ice floats.
  • Means ice forms an insulating layer on top of water in cold temperatures.
  • This means water below doesn’t freeze so organism that live in water like fish don’t freeze and can still move around.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is a Monomer?

A

Monomers are small units which are the components of larger molecules. E.g monosaccharides such as glucose and Amino Acids.

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

What is a Polymer?

A

Polymers are molecules made from monomers joined together. E.G Amino Acids join together form a polypeptide chain.

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

A condensation reaction

A

A condensation reaction is a reaction which joins monomers by chemical bonds and it involves the loss of a water molecule.

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

What are the 3 Main carbohydrates?

A
  • Monosaccharides (sugar).
  • Disaccharid (sugar).
  • Polysaccharides
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Carbohydrate def

A
  • Contains only oxygen carbon and Hydrogen.
  • Stores energy in plants and animals.
  • Cellulose cell wall dependant on structural role of some carbohydrates.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Glucose+Glucose=

A

Maltose

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

Glucose+Fructose=

A

Sucrose

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

Glucose+Galactose=

A

Lactose

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

Disaccharides def

A
  • Molecule consisting of 2 monosaccharides joined by a glyosidic bonds by a condensation reaction.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Monosaccharides def

A
  • A molecule consisting of a single sugar.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Polysaccharide def

A
  • A polymer made from many sugar monomers (monosaccharides).
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is a Monomer

A
  • Single Molecule.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How is cellulose adapted to their function in plant cells?

A
  • Long Chains which are Linked to form fibrils. This Provide strength to cell wall.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Starch function

A
  • Main energy storage in plants.

- Mixture of two polysaccharides, Amylose and Amylopectin.

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

Starch adaptations.

A
  • Amylose,Compact so it’s good for storage because you can fit more into a small space.
  • Amylopectin,Branches allow enzymes that break down the molecule to reach the glycolic bonds easily.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Glycogen.

A
  • Main energy storage material in animals.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Glycogen adaptations

A
  • Many side branches means stored glucose can be released easily.
  • Compact molecule which is good for storage.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Cellulose

A
  • The major component of cell walls in plants.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Triglyceride structure.

A
  • one molecule of glycerol and three fatty acids (tails) attached to it.
  • Tails are hydrophobic.
  • Contain ester bonds. (Broken in hydrolysis reactions)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Esterification.

A
  • The process by which triglycerides are synthesised.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Difference between Saturated and Unsaturated fatty acids.

A
  • Saturated=No double bonds between carbon atoms.

- Unsaturated=At least one double bond between carbon atoms. (Causes the chain to kink)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Similarity and difference between a phospholipid and triglyceride.

A 
Similarity= They are both macromolecules.
Difference= One of the fatty acids(hydrophobic) in a phospholipid is replaced by a phosphate group (hydrophilic).
30
Q

Triglyceride properties.

A
  • Long hydrocarbon tails of the fatty acids contain lot of chemical energy, means a load of energy is released when broken down.
  • Insoluble, Don’t cause water to enter the cell by osmosis, which would make them swell.
31
Q

Phospholipid proporties

A
  • Hydrophilic heads and hydrophobic tails, meaning they form a double layer with their heads facing out towards the water.
  • Centre of the Bilayer is hydrophobic so the membrane acts as a barrier to water soluble substances.
32
Q

Cholesterol properties.

A
  • Small size and flattened shape, allows it to fit between the phospholipid’s in the membrane.
  • They bind to phospholipids tails, causing them to pack more close together,making the membrane more rigid.
33
Q

What are the three ‘main’ lipids?

A
  • Cholesterol.
  • Phospholipids.
  • Triglycerides.
34
Q

What are the monomers in a protein?

A

-Amino Acids.

35
Q

What is a dipeptide?

A

When two Amino Acids join together.

36
Q

What is a polypeptide?

A

When more than two amino acids join together.

37
Q

Amino Acid structure.

A
  • A Carboxyl group (-COOH) and an amine group(-NH2) attached to a carbon atom.
38
Q

What is the difference between the structure of Amino Acids?

A
  • The variable group they contain.
39
Q

What bond join up Amino Acids and how is it broken/formed.

A
  • Peptide bond.
  • Formed by a condensation reaction, molecule of water released.
  • Broken by a hydrolysis reaction, molecule of water added.
40
Q

What are the 4 protein structural levels?

A
  • Primary structure.
  • Secondary structure.
  • Tertiary Structure.
  • Quaternary structure.
41
Q

What is the Primary structure?

A
  • The sequence or amino acids in a polypeptide chain.
42
Q

What is the secondary structure?

A
  • Hydrogen bonds form between the amino acids in the chain.

- This makes it coil into an alpha helix or fold into a beta pleated sheet.

43
Q

What is the tertiary structure of a protein?

A
  • Coiled chain of Amino acids is coiled and folded further.
  • More bonds form between different parts of polypeptide chain.
  • Final 3D structure for protein made from 1 polypeptide chain.
44
Q

What is the quaternary structure of proteins?

A
  • The way polypeptide chains are assembled together. e.g Haemoglobin.
  • Final 3D structure for protein made from more than 1 polypeptide chain.
45
Q

Primary structure bonds.

A
  • Peptide bonds between Amino Acids.
46
Q

Secondary structure bonds .

A
  • Hydrogen bonds.
47
Q

Tertiary structure bonds

A
  • Ionic bonds (Attraction between negatively and positively charged R groups)
  • Disulphide bonds.
  • Hydrogen bonds.
48
Q

Quaternary structure bonds.

A
  • Determined by the tertiary structure of the individual polypeptide chains being bonded together.
  • Therefore, can be influenced by all the bonds.
49
Q

Globular protein

A
  • Round and compact.
  • Hydrophilic R groups on the Amino Acids tend to be pushed on the outside of the molecule, this makes globular proteins soluble, so they’re easily transported in organisms.
50
Q

Examples of globular proteins

A
  • Haemoglobin.(Carries oxygen around the body in red blood cells).
  • Insulin.(Helps regulate blood glucose levels).
  • Amylase. (Catalyses the breakdown of starch in the digestive system).
51
Q

Fibrous protein.

A
  • Tough and rope-shaped.
  • Insoluble.
  • Fairly unreactive.
52
Q

Examples of fibrous proteins.

A
  • Collagen (Found in animal connective tissues, strong molecule, minerals can bind to increase rigidity).
  • Keratin.(Found in skin, nails and hair, can be flexible or hard and tough.
  • Elastin (Found in connective tissues, allows tissues to turn to its original shape after is has been stretched.
53
Q

What is a conjugated protein?

A

-A protein with a non-protein group attached.

54
Q

What are inorganic ions?

A
  • An atom that has an electric charge.
55
Q

What is a ion with a positive charge called?

A
  • Cations.
56
Q

Cations.

A
  • Calcium (ca2+).
  • Sodium (Na+).
  • Potassium (K+)
  • Hydrogen (H+).
  • Ammonium (NH4+)
57
Q

What are ions with a negative charge called?

A
  • Nitrate (NO3-)
  • Hydrogencarbonate (HCO3-).
  • Chloride (Cl-)
  • Phosphate (PO43-)
  • Hydroxide (OH-)
58
Q

Biuret test for proteins

A
  • Add a few drops of sodium hydroxide to the solution (so it becomes an alkaline).
  • Add some copper surface solution.
  • Protein present=purple.
  • No protein= stays blue.
59
Q

Iodine test for starch.

A
  • Add iodine dissolved in potassium solution to the test sample.
  • Starch present=Dark blue-black.
  • No starch= stays browny-orange.
60
Q

Emulsion test for lipids.

A
  • Shake the test substance with ethanol for about a minute, then pour the solution into water.
  • Lipid present=Milky.
  • No lipid= Solution remains clear.
61
Q

Benedicts test for reducing sugars.

A
  • Add benidicts to a sample and heat it in a water bath.
  • Reducing sugars present= Coloured precipitate, Green-Yellow-Orange-Brick red. (The higher than concentration of reducing sugar present, the further the colour change.
  • No reducing sugar present= Sample stays blue.
62
Q

Benedicts test for non-reducing sugars. (E.g sucrose).

A
  • Add dilute hydrochloric acid to the sample and heat it in a water bath.
  • Neutralise the solution it’s sodium hydrogen carbonate.
  • Non-reducing sugar present=Coloured precipitate.
  • No Non-reducing sugar present= stays blue.
63
Q

What is a colorimeter?

A
  • A device that measures the strength of a coloured solution by seeing how much light passes through it.
64
Q

Chromatography

A
  • Draw a pencil line near the bottom of a piece of chromatography paper.
  • Put a concentrated spot of the mixture of the molecule on it.
  • Add a small amount of prepared solvent to a beaker and dip the bottom of the paper into it.
  • Cover with a lid to stop the solvent evaporating.
  • When the solvents near the top, take the paper out and marker the solvent front with pencil.
  • Let the paper dry out and then analyse it.
65
Q

Rf values.

A
  • Distance travelled by spot/distance travelled by solvent.
66
Q

What Is the mobile phase in chromatography?

A
  • Where the molecules can move.
67
Q

What is the stationary phase in chromatography?

A
  • Where the molecules Can’t move,
68
Q

Which chemical elements make up carbohydrates?

A
  • C,H and O
69
Q

Which chemical elements make up lipids?

A
  • C, H and O
70
Q

Which chemical elements make up proteins?

A
  • C, H, O and S
71
Q

Which chemical elements make up nucleic acids?

A
  • C,H,O,N and P

Year 12 Biology (module 2) (10 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions