Brainscape's Knowledge GenomeTM

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


See full index

Biology > Biological Molecules > Flashcards

Biological Molecules Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

What is a monomer?

A

A single unit that can be repeated

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

What is a polymer?

A

A long chain of repeating monomers

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

What are reducing sugars?

A

Sugars that can give electrons to other molecules

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

What are monosaccharides?

A

A single monomer of a carbohydrate

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

What are examples of monosaccharides?

A
  • glucose
  • galactose
  • fructose
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are examples of reducing sugars?

A

All monosaccharides and the disaccharides maltose and lactose

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

What are isomers?

A

Compounds that have the same chemical formulas but different atom arrangements e.g. alpha and beta glucose

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

How do you test for reducing sugars?

A
  • add Benedict’s reagent
  • boil in 90º water bath for 5 minutes
  • a positive result is a colour change from blue to green/yellow/orange/brick red
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Is a reducing sugar test quantitative or qualitative?

A

Qualitative

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

What method is used to get a quantitative result for a reducing sugar test?

A
  • serial dilution
  • create serial dilutions of 2%, 0.2%,0.002% and 0.0002%
  • do reducing sugar test
  • use a colorimeter to test for absorbance
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What bonds join monosaccharides?

A

Glycosidic bonds

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

What reaction forms glycosidic bonds?

A

Condensation reaction (removal of water)

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

What reaction breaks glycosidic bonds?

A

Hydrolysis reaction (addition of water)

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

What monomers make maltose?

A

2 alpha glucose molecules

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

What monomers make sucrose?

A

Alpha glucose and fructose

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

What monomers make lactose?

A

Alpha glucose and galactose

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

What are examples of polysaccharides?

A
  • cellulose in cell walls
  • chitin in fungi and exoskeletons of insects
  • glycogen which is the store of sugar in animals
  • starch which is the store of sugar in plants
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are examples of non reducing sugars?

A

Sucrose

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

How do you test for non reducing sugars?

A
  • must receive a negative Benedict’s test
  • add acid (HCl)
  • leave in a 90º water bath for 5 minutes
  • neutralise with an alkali (sodium hydroxide)
  • redo Benedict’s test
  • positive result is a colour change from blue to green/yellow/orange/brick red
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How do you test for starch?

A
  • add potassium iodide
  • positive result is a colour change from orange to blue black
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is chitin?

A
  • used in fungus cell walls and exoskeletons of insects
  • made of beta glucose
  • contains NH2
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is the structure of starch?

A
  • chains of alpha glucose
  • insoluble
  • branched strands have lots of terminal ends
  • unbranded strands are highly coiled into a helix shape
  • large molecule
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is the function of starch?

A
  • main energy storage material in a plant
  • doesn’t dissolve in water so no effect on water potential so no movement of water buys osmosis so the cell won’t burst
  • unbranched chains are compact for storage
  • branched chains allow fast, easy hydrolysis of glycosidic bond so faster rate of respiration
  • large molecule so cannot leave the cell
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is the structure of glycogen?

A
  • alpha glucose molecule chains
  • highly branched
  • compact
  • insoluble
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What is the function of glycogen?

A
  • main energy storage material in animals
  • rapid hydrolysis of glycosidic bonds for respiration
  • compact for storage
  • doesn’t dissolve in water so no effect on water potential so no effect on osmosis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is the difference between straight glucose chain and a branched chain?

A
  • straight molecule chains have a 1-4 glycosidic bond whereas a branched chain has a 1-6 glycosidic bond
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is the structure of cellulose?

A
  • beta glucose molecule chains
  • adjacent monomers are inverted to form glycosidic bonds
  • long unbranched straight chains
  • chains run parallel to eachother and form microfibrils
  • form strong fibres
28
Q

What is the function of cellulose?

A
  • major component of a plant cell wall
  • structural support
29
Q

Where are lipids found?

A
  • cell membranes
  • fat stores
  • nerve cells
30
Q

How much more energy does the same mass of lipids produce than carbohydrates?

A

Twice the amount

31
Q

Why are fats good for waterproofing?

A

Insoluble in water

32
Q

Why are fats good for insulation?

A

They are slow conductors of heat and energy

33
Q

Where are fats used for protection?

A

Often stored around delicate organs to prevent damage

34
Q

What is a triglyceride?

A
  • a glycerol molecule
  • 3 fatty acid chains
  • joined by an ester bond between each fatty acid and the glycerol
35
Q

What is the bond between the fatty acid and glycerol in a lipid molecule

A

Ester bond

36
Q

What reaction forms ester bonds?

A

Condensation reaction (removal of water)

37
Q

What reaction breaks an ester bond?

A

Hydrolysis reaction (addition of water)

38
Q

Is a triglyceride a polymer?

A

No

39
Q

What do fatty acid chains all have in common?

A

A carboxylate group (COOH)

40
Q

What causes the different properties of lipid molecules?

A

Variations in the fatty acid chain

41
Q

What is a saturated fatty acid chain?

A

a hydrocarbon chain that has no double carbon bonds

42
Q

What is an unsaturated fatty acid chain?

A
  • monounsaturated means that the hydrocarbon chain has 1 double carbon bond
  • polyunsaturated means the hydrocarbon chain has multiple double carbon bonds
43
Q

What is the structure of phospholipids?

A
  • glycerol molecule
  • 2 fatty acids
  • phosphate group
  • 3 ester bonds
44
Q

Is the phosphate head attracted to water?

A

Yes, it is hydrophilic

45
Q

Is the fatty acid tail attracted to water?

A

No it is hydrophobic

46
Q

What is the function of phospholipids?

A
  • form a phospholipid bilayer
  • in the cell membrane
47
Q

How do you test for lipids?

A
  • dissolve the sample in ethanol and shake it
  • add distilled water and shake it
  • a positive result is a cloudy white emulsion
48
Q

What is the structure of amino acids?

A
  • an amine group (NH2)
  • a carboxyl group (COOH)
  • an R group (the variation between amino acids)
  • a carbon atom
49
Q

What are amino acids a monomer of?

A

Polypeptides

50
Q

What bond forms between amino acids in a polypeptide?

A

Peptide bond

51
Q

What reaction forms a peptide bond?

A

Condensation reaction (removal of water)

52
Q

What reaction breaks a peptide bond?

A

Hydrolysis reaction (addition of water)

53
Q

What is the primary structure of proteins?

A

The specific sequence of amino acids

54
Q

What is the secondary structure of proteins?

A

Folding/twisting of the amino acid chain into an alpha helix or a beta pleat

55
Q

What is the tertiary structure of proteins?

A
  • further twisting and folding
  • held together by disulphide bridges (strongest), ionic bonds (weaker), and hydrogen bonds (strong in numbers)
56
Q

What is the quaternary structure of proteins?

A
  • the addition of multiple polypeptide chains into one molecule
  • MAY have a prosthetic group
57
Q

What is the test for proteins?

A
  • add biuret solution
  • positive result is a colour change from blue to purple
58
Q

What is the structure of enzymes?

A
  • tertiary globular proteins
  • has a specific active site which is complimentary to a specific substrate
59
Q

What is an enzyme-substrate complex?

A

The combination ad binding of an enzyme and substrate

60
Q

What is the lock and key theory of enzymes?

A

The enzyme has an active site which is exactly complimentary to the substrate and breaks it down

61
Q

What is the induced fit theory of enzymes?

A

The enzyme is complimentary to the substrate but changes shape once E-S complex is formed and puts more strain on the on and distorts the bonds in the substrate to break it down

62
Q

How does temperature affect the rate of enzyme action?

A
  • when temperature is low, particles have less kinetic energy so there is less E-S complexes
  • at optimum temperature, enzymes have lots of kinetic energy so lots of E-S complexes formed
  • when temperature is high, particles have too much kinetic energy to H bonds in tertiary structure are broken, active site denatures, less E-S complexes formed
63
Q

How does pH affect the rate of enzyme action?

A
  • at low pH, there are lots of hydrogen ions which affect the ionic bonds so active sites denature so less E-S complexes formed
  • at optimum pH, lots of collisions between enzymes and substrates so there is the maximum amount of E-S complexes
  • lots of hydroxide ions which affect ionic bonds so active site denatures and less E-S complexes formed
64
Q

How does substrate concentration affect rate of enzyme
action?

A
  • few substrate molecules limit chance of successful collisions, many active sites empty, few E-S complexes
  • more substrate molecules increases chance of successful collisions so there is more E-S complexes
  • excess substrate molecules but active sites are full so there is no increase in rate
65
Q

How does enzyme concentration affect rate of enzyme action?

A
  • new enzymes, limits rate of successful collisions, not enough active sites available so fewer E-S complexes
  • lots of enzymes, increased chance of successful collisions, max amount of E-S complexes
  • excess enzymes so there is empty active sites so there is no increase in rate
66
Q

How do competitive inhibitors work?

A
  • they are a similar shape to the substrate
  • bind to the active site
  • compete with the substrate
  • rate of reaction decreases but will still happen
67
Q

How do non-competitive inhibitors work?

A
  • different shape to substrate
  • attach to allosteric site
  • alters shape or enzymes active site
  • can get stuck and permanently change active site shape

Biology (11 decks)

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