3.1, 3.2, 3.3: Biological Elements, Water, Carbohydrates Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

What are the 4 key elements that all living things are primarily made from?

A

Carbon, Hydrogen, Oxygen and Nitrogen

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

Why is life on Earth often referrred to as being “carbon-based”?

A

Because carbon forms the backbone of most biological molecules

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

What is an atom called if it has lost electrons?

A

Cation

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

What is an atom called if it has gained electrons?

A

Anion

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

What elements are in Carbohydrates?

A

Carbon Hydrogen and Oxygen

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

What elements are in lipids?

A

Carbon, Hydrogen and Oxygen

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

What elements are in Proteins?

A

Carbon, Hydrogen, Oxygen, Nitrogen and Sulfur

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

What elements are in Nucleic Acids?

A

Carbon, Hydrogen, Oxygen, Nitrogen and Phosphorus.

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

What are polymers?

A

Long-chain molecules made by the linking of multiple individual molecules in a repeating pattern.

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

What are organic molecules?

A

Molecules that contain hydrogen and carbon

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

What is the definition of hydrophobic?

A

Repels water

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

What does hydrophilic mean?

A

Attracted to water

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

What does intermolecular mean?

A

Between molecules

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

What does intramolecular mean?

A

Within molecules

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

What does polar mean?

A

Having regions of both negativity and positivity, but with an overall neutral charge

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

What is the definition of a property?

A

The way something behaves.

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

What is the definition of cohesion?

A

Attraction between molecules

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

What is the definition of adhesion?

A

Attraction to other molecules

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

What is the definition of electronegative?

A

Tending to acquire electrons.

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

Why is water polar?

A

-The electrons are shared unevenly. The oxygen has a greater share of negative electrons, so it is slightly negative, and the hydrogen is slightly positive

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

What gives water its unique characteristics?

A

The hydrogen bonds formed between molecules

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

Is water adhesive or cohesive?

A

Both

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

What makes water a solvent?

A

The fact that it is polar.

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

Describe the solvent property of water

A

-Allows hydrophilic substances to be dissolved
-Acts as a medium for chemical reactions
-Also helps transport dissolved substances into and out o cells.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

State the properties of water.

A

Cohesive, adhesive, univesal solvent, high head capacity, high latent heat of vaporisation, lower density as a solid than as a liquid, polar

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Describe the density of water.

A

-The density of water is similar to the density of most organisms, which enables organisms to live in water without sinking
-Water in solid form (ice) is less dense than water so it floats on the surface, insulating the water below.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What property gives water a high heat capacity?

A

-Because of its hydrogen bonds.
-Lots of weak hydrogen bonds add up to make a strong intermolecular force of attraction.
-These bonds require a lot of energy to break for the temperature to increase.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

How does water buffer temperature change?

A

Water has to absorb/lose a large amount of energy before its temperature can change, which takes a large amount of time.

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

What does it mean that water is a metabolite?

A

Water can be used as a reactant in many chemical reactions in cells.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What is a condensation reaction?

A

A type of chemical reaction in which water is produced when smaller molecules are joined together to make bigger ones.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What is a hydrolysis reaction?

A

A type of chemical reaction in which large cells are broken down into smaller ones using water.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Why does water have a “skin” of surface tension?

A

Water molecules are more strongly cohesive to eachother than they are to air.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What is capillary action?

A

The process by which water can travel up a narrow tube against the force of gravity.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What is a functional group?

A

A group that is added to a molecule and changes its properties.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What is the Hydroxyl group?

A

“-OH”

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

How does the hydroxyl group help a molecule to dissolve when it is added to it?

A

Because the hydroxyl group is polar.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

What is the carboxylic acid group?

A

-COOH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

What is the molecular formula of Alpha Glucose?

A

C6H1206

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

What makes glucose polar?

A

The presence of the hydroxyl group

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

What are the two structural variations of glucose?

A

Alpha and Beta Glucose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

What is the definition of an isomer?

A

Compounds with the same formula but a different arrangement of atoms in the molecule and different properties.

42
Q

Is glucose soluble or insoluble?

A

Soluble

43
Q

What makes Beta glucose different to Alpha?

A

The hydroxyl group has been flipped upside down on one side

44
Q

What are the functions of carbohydrates?

A

-Energy sources (sugars, eg glucose)
-Long term energy stores (eg starch for plants, glycogen for animals)
-Act as structures (eg cellulose in plant cell walls)

45
Q

Give 4 examples of monosaccharides

A

Glucose, fructose, galactose, ribose

46
Q

What does hexose mean?

A

Containing 6 carbon atoms

47
Q

Which monosaccharides are hexose?

A

Glucose, fructose and galactose

48
Q

Which monosaccharides are pentose?

A

Ribose

49
Q

What do two or more monosaccharides linked together form?

A

Polysaccharides

50
Q

Give some examples of polysaccharides

A

Glycogen, cellulose and starch

51
Q

What are the products of two alpha glucoses reacting with eachother?

A

Maltose and water

52
Q

What is the name of the bond between two glucose molecules?

A

A 1-4 glycosidic bond

53
Q

What is maltose made of?

A

Two alpha glucoses

54
Q

What is sucrose made of?

A

Alpha glucose and fructose

55
Q

What is lactose made of?

A

Glucose and galactose

56
Q

What is ribose?

A

A pentose monosaccharide. The sugar present in RNA nucleotides

57
Q

What is deoxyribose?

A

A pentose monosaccharide. The sugar present in DNA nucleotides.

58
Q

What is glucose stored as?

A

Starch by plants or as glycogen by animals and fungi

59
Q

How do you release glucose for respiration?

A

-Starch or glycogen has to undergo hydrolysis, requiring the addition of water molecules.
-The reaction is catalysed by enzymes.

60
Q

What are the two key properties of glucose?

A

It is small and soluble

61
Q

Why is it important that glucose is small?

A

So it can easily pass into cells through the cell membrane

62
Q

What is the difference between ribose and deoxyribose?

A

On the second carbon, ribose has a hydroxide but deoxyribose only has a hydrogen

63
Q

What two forms does starch come in?

A

An unbranched form (amylose), and a branched form (amylopectin)

64
Q

Describe the structure of amylose.

A

-A polysaccharide made of chains of alpha-glucose molecules linked by 1-4 glycosidic bonds
-The glucose molecules are linked together by a condensation polymerisation reaction
-The chains are unbranched
-Chain is coiled into a helix that is maintained by hydrogen bonds holding the sugars together, making it compact and less soluble

65
Q

Describe the features of amylose

A

-Large molecule
-Compact
-Can be hydrolysed
-Soluble
-Large polymer

66
Q

Describe the structure of amylopectin

A

-Polysaccharide made of chains of alpha glucose molecules, linked together by 1-4 glycosidic bonds
-Once in every 25 glucose subunits, a 1-6 glycosidic bond is formed, allowing the glucose to branch out

67
Q

Describe the features of amylopectin

A

-Compact
-Insoluble, (no effect on water potential)
-Can be hydrolysed faster than amylose
-Branched
-Large polymer

68
Q

Why can amylopectin be broken down/hydrolysed faster than amylose?

A

Because it is branched, so there are more exposed ends for the enzyme to work, so more available sites to work and remove glucose.

69
Q

What are the uses of starch?

A

-Stores energy in plant cells
-Can be broken down into smaller molecules of maltose through hydrolysation

70
Q

If a chemical is insoluble, how does it effect the water potential of a cell?

A

It has no effect on the water potential as it has no osmotic effect.

71
Q

Why is it important that energy stores are compact?

A

So that it can be an efffective store of energy (more can be stored in a small space)

72
Q

What cells is glycogen found in?

A

Animal cells (especially liver and muscle), and bacteria

73
Q

What is glycogen made of?

A

Alpha glucose molecules

74
Q

What bonds does glycogen contain?

A

1-4 glycosidic bonds and 1-6 glycosidic bonds

75
Q

What is the difference between a 1-4 glycosidic bond and a 1-6 glycosidic bond?

A

1-6 glycosidic bond is used to connect branches, 1-4 glycosidic bond is used to connect molecules.

76
Q

How branched is glycogen?

A

More branched than amylopectin, with a new branch roughly every 10 sugars.

77
Q

What is the shape of glycogen?

A

Helical

78
Q

What holds the coil shape of glycogen?

A

Hydrogen bonds between glucose molecules

79
Q

Is glycogen soluble or insoluble?

A

Insoluble

80
Q

What is the use of glycogen?

A

Store of energy in cells.

81
Q

Why do animals use glycogen as an energy store but not plants?

A

-Animals are metabolically active, meaning they require energy for respiration faster than plants.
-So more glucose has to be converted to energy at any given time in animals than in plants
-Because glycogen is so highly branched, it is very compact and has more terminal glucose molecules that can be extracted at any given time.

82
Q

What is the name for the ends of branches in polysaccharides?

A

Terminal glucose molecules

83
Q

If a polysaccharide is more branched, can it be hydrolysed faster or slower?

A

Faster

84
Q

What is cellulose a polymer of?

A

Beta glucose molecules

85
Q

What are the monomers in cellulose joined by?

A

1-4 glycosidic bonds

86
Q

Describe the layout of the monomers in cellulose.

A

Because the ends of the hydroxyl groups are too far apart, they cannot link up. So, every alternative beta glucose monomer is flipped upside down, and then bonded to the next monomer.

87
Q

Describe the structure of cellulose

A

Uncoiled, made of straight, unbranched chains that run parallel to eachother, with hydrogen bonds forming cross-linkages between adjacent chains

88
Q

Where are the hydrogen bonds in cellulose?

A

Between the hydroxyl groups of Beta Glucose

89
Q

What gives cellulose its tensile strength and rigidity?

A

Hydrogen bonds between monomers

90
Q

What are the properties of cellulose?

A

-High tensile strength
-Insoluble
-Rigid on a large scale, flexible on a small scale
-Unreactive

91
Q

What makes cellulose insoluble?

A

Strong hydrogen bonds.

92
Q

What do chains of cellulose molecules form?

A

Microfibrils

93
Q

What do bundles of microfibrils grouped together make?

A

Macrofibrils

94
Q

What are macrofibrils?

A

Bundles of microfibrils grouped together

95
Q

What are microfibrils?

A

Chains of cellulose molecules

96
Q

What makes up cellulose fibres?

A

Macrofibrils

97
Q

What do macrofibrils make up?

A

Cellulose fibres

98
Q

What are cellulose fibres?

A

A major component in cell walls of plant cells that provide tensile strength and rigidity.

99
Q

How do cellulose fibres provide rigidity to cell walls?

A

They provide an inward force to the cell, which prevents it from bursting and maintains turgor inside the cells, which helps support the tissues.

100
Q

Why are cellulose fibres an important part of our diet?

A

Because it is hard to break down into its Beta-Glucose monomers, it provides roughage needed in a healthy digestive system.

101
Q

What can cellulose be hydrolysed by?

A

The enzyme cellulase, which is present in the digestive system of herbivores (ie not in humans).

102
Q

What molecule can Lysozyme break down?

A

Peptidoglycan