Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

biology > biological molecules > Flashcards

biological molecules Flashcards

(61 cards)

Start Studying
1
Q

what are the five properties that make water important for organisms [5 marks]

A

high specific heat capacity = temperature buffer

high latent heat of vaporisation = cooling effect

solvent = transport of substances

metabolite = in photosynthesis, hydrolysis, respiration, condensation reactions

strong cohesion between water molecules = supports columns of water, e.g. transpiration stream, through xylem in plants

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

What are the monomers of carbohydrates? give examples too

A

Monosaccharides such as glucose, galactose, and fructose.

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

What is a condensation reaction?

A

A reaction where two molecules join and release a molecule of water.

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

What bond forms between two monosaccharides?

A

A glycosidic bond.

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

What is the disaccharide formed from two glucose molecules?

A

Maltose.

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

What is the disaccharide formed from glucose and fructose?

A

Sucrose.

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

What is the disaccharide formed from glucose and galactose?

A

Lactose.

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 and heat; a brick-red precipitate indicates reducing sugar.

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

How do you test for non-reducing sugars?

A

Hydrolyse with HCl, neutralise, then do Benedict’s test again.

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

What is the structure of starch?

A

A mixture of amylose (unbranched) and amylopectin (branched).

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

How is starch adapted to its function?

A

Insoluble, compact, and branched for fast energy release.

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

How is glycogen adapted to its function?

A

Highly branched for fast glucose release, compact for storage.

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

What is the structure of cellulose?

A

Long unbranched chains of β-glucose with hydrogen bonds forming microfibrils.

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

How is cellulose adapted to its function?

A

Strong fibres give structural support to plant cell walls.

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

What is the structure of a triglyceride?

A

One glycerol and three fatty acids joined by ester bonds.

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

What is the difference between saturated and unsaturated fatty acids?

A

Saturated have no double bonds; unsaturated have one or more.

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

What is the structure of a phospholipid?

A

Glycerol, two fatty acids, and a phosphate group.

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

How are phospholipids arranged in membranes?

A

In a bilayer with hydrophobic tails inward and hydrophilic heads outward.

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

How do you test for lipids?

A

add ethanol, then add water, shake
a white emulsion indicates lipid.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
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
21
Q

What bond forms between amino acids?

A

Peptide bond.

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

What is the primary structure of a protein?

A

The sequence of amino acids, joined together by peptide bonds, through condensation reactions

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

What is the secondary structure of a protein?

A

Alpha-helix or beta-pleated sheet formed by hydrogen bonding.

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

What is the tertiary structure of a protein?

A

3D shape formed by hydrogen bonds, ionic bonds, and disulfide bridges.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What is the quaternary structure of a protein?
Structure formed from more than one polypeptide chain.
26
How do you test for proteins?
Biuret test: add Biuret reagent; purple colour indicates protein.
27
What type of molecule are enzymes?
Proteins.
28
How do enzymes work?
They lower the activation energy by forming enzyme-substrate complexes.
29
What is the lock and key model?
The substrate fits the enzyme's active site exactly.
30
What is the induced fit model?
The enzyme changes shape slightly to fit the substrate.
31
What factors affect enzyme activity?
Temperature, pH, substrate concentration, enzyme concentration, competitive or non-competitive inhibitors
32
What is enzyme denaturation?
Loss of enzyme's active site shape, stopping function.
33
What are competitive inhibitors?
Molecules that bind to the active site, blocking the substrate.
34
What are non-competitive inhibitors?
Molecules that bind elsewhere, changing the active site shape.
35
What are the monomers of nucleic acids?
Nucleotides.
36
What are the components of a DNA nucleotide?
Deoxyribose, phosphate group, nitrogenous base.
37
What are the four DNA bases?
Adenine, thymine, cytosine, guanine.
38
What is the base pairing rule?
A pairs with T, C pairs with G.
39
What bond joins nucleotides?
Phosphodiester bond.
40
What is the structure of DNA?
Double helix with antiparallel strands.
41
How is DNA adapted to its function?
Stable, double-stranded, complementary base pairing.
42
What is the role of RNA?
Transfers genetic information from DNA to ribosomes.
43
What base does RNA have instead of thymine?
Uracil.
44
What sugar does RNA contain?
Ribose.
45
What is ATP?
Adenosine triphosphate – an immediate energy source.
46
How is ATP broken down?
By hydrolysis using ATP hydrolase to form ADP + Pi.
47
How is ATP resynthesised?
From ADP + Pi using ATP synthase during respiration or photosynthesis.
48
Why is water a polar molecule?
It has a partial negative charge on oxygen and partial positive on hydrogen.
49
What bonds form between water molecules?
Hydrogen bonds.
50
What are key properties of water?
High specific heat capacity, high latent heat, cohesive, solvent, metabolite.
51
Why is water a good solvent?
It can dissolve ionic and polar substances.
52
Why is water important in metabolism?
It is a reactant in hydrolysis and photosynthesis.
53
What is the role of iron ions in biology?
Part of haemoglobin, binds oxygen.
54
What is the role of hydrogen ions?
Determine pH – the higher the H⁺ concentration, the lower the pH.
55
What is the role of sodium ions?
Used in co-transport of glucose and amino acids.
56
What is the role of phosphate ions?
Component of DNA, RNA, and ATP.
57
what bonds are present within water molecules?
covalent bonds
58
what bonds are present between other water molecules/ polar substances?
hydrogen bonds
59
how does the presence of a double bond in lipids affects its' boiling point?
lowers BP
60
difference in pyrimidines and purines, and which bases are which?
pUrines = 2 rings = A , G pyrimidInes = 1 ring = C, T, U
61
do bacteria have DNA or RNA?
they can have either

biology (7 decks)

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