Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Biology > Biological Molecules > Flashcards

Biological Molecules Flashcards

(56 cards)

Start Studying
1
Q

Monomer is …

A

small, single molecule many of which can be joined together to form a polymer

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

Polymer is…

A

large molecule made up of many similar monomers joined together

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

A condensation reaction..

A

Joins 2 molecules together, eliminates a water molecules, forms a chemical bond

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

A hydrolysis reaction

A

Separates 2 molecules, requires addition of a water molecule, breaks a chemical bond

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

Disaccharide e.g.

A

glucose+glucose →maltose
glucose+fructose →sucrose
glucose+galactose →lactose

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

Monosaccharides are…

A

the monomers from which larger carbohydrates are made

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

What bond is formed from a condensation reaction between 2 monosaccharides

A

Glycosidic

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

Difference between alpha and beta glucose

A

OH group is below C1 on a-glucose, but above C1 on b-glucose
*remember ABBA (honourable mamma mia mention)
Alpha
Below
Beta
Above

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

Glycogen: function and structure

A

Energy store in animal cells
Polysaccharide of a-glucose with C1-C4 and C1-C6 glycosidic bonds so branched

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

Structure of glycogen related to its function

A

Branched; can be rapidly hydrolysed to release glucose for respiration to provide energy
Large polysaccharide molecule; cant leave the cell
Insoluble in water; water potential of cell isn’t affected

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

Starch: function and structure

A

-Energy store in plant cells
-Polysaccharide of a-glucose
-Mixture of amylose and amylopectin
-Amylose (C1-C4 glycosidic bonds)
-Amylopectin (C1-C6 glycosidic bonds) so branched

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

Structure of starch related to its function

A

Helical; compact for storage in cells
Large polysaccharide; can’t leave cell
Insoluble in water; water potential of cell not affected

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

Cellulose: function

A

Provides strength and structural support to plant cell walls

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

Structure of cellulose related to its function

A

-Every other beta glucose molecule is inverted in a long, straight, unbranched chain
-Many H bonds link parallel strands to form microfibrils
-H bonds are strong and high in number
-Providing strength and structural support to plant cell walls

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

Benedicts test for reducing sugars

A

-Add benedict’s reagent (blue) to sample
-Heat in boiling water bath
-Positive= green/yellow/orange/red (depending amount of reducing sugar conc)

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

Benedicts test for non reducing sugar

A

-Add a few drops on dilute HCl ( to hydrolyse sugar)
-Heat in a boiling water bath
-Neutralise with sodium bicarbonate
-Add Benedict’s and heat again
-Non reducing sugar present= green/yellow/orange/red (depending amount of reducing sugar conc)

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

Determining glucose concentration

A

-Produce a dilution series of glucose solutions of known concentrations
-Perform a Benedict’s test on each sample
-Use same amount for each solution
-Remove precipitate by filtering
-Using a colorimeter measure the absorbance and plot a calibration curve
-Calibrate using unreacted Benedict’s
-Use red filter
-Absorbance against glucose concentration
-Repeat with unknown samples and use graph to determine glucose concentrations

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

Iodine test for starch

A

-Add iodine dissolved in potassium iodide to solution and shake
-Blue/black colour =positive

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

Formation of triglycerides

A

Condensation of 1 glycerol and 3 fatty acids, forming an ester bond

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

Properties related to a triglycerides structure

A

-Energy storage molecule
-High ratio of C-H bonds to C atoms in hydrocarbon tail so more energy is released compared to the same mass of carbohydrates
-Insoluble in water so no effect on water. potential

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

Formation of phospholipids

A

One of the fatty acids of a triglyceride is substituted by a phosphate-containing group

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

Properties related to a phospholipids structure

A

-Form bilayer in cell membrane, allowing diffusion of non-polar, small molecules
-Phosphate heads are polar/hydrophilic
-Fatty acids tails are non-polar/hydrophobic

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

Emulsion test for lipids

Study These Flashcards
A

Add ethanol and shake
Then add water
Positive; milky/cloudy white emulsion

24
Q

General structure of amino acids

Study These Flashcards
A

-amine group
-carboxyl group
-R group (variable)
-CH

25
Amino acids can form
-Dipeptides; 2 amino acids joined -Polypeptide; many amino acids joined
26
Structure of proteins
Primary; Sequence of amino acids in a polypeptide chains Secondary; H bonding between amino acids causes polypeptide chain to fold into a repeating pattern (a-helix or b-pleated sheets) Tertiary; Overall 3D structure of a polypeptide held together by interactions between amino acid side chains: ionic. bonds/disulphide bridges/H bonds Quaternary; Some proteins made of 2+ polypeptide chains held together by more H, ionic and disulfide bonds
27
Biuret test for proteins
-Add biuret solution; NaOH + CuSO4 -Positive= purple colour -Detects presence of peptide bond
28
Lock and key model (old)
-Active site is a fixed shape and is complementary to one substrate -After a successful collision, an E-S complex forms leading to a reaction
29
Induced fit model (accepted)
-Before reaction, enzyme AS isn't completely complementary to specific substrate -AS shape changes slightly as substrate binds and E-S complex forms -This distorts bonds in sublate leading to a reaction
30
The specificity of enzymes
-Enzymes have a specific tertiary stucture and active site (determined by the sequence of amino acids in primary structure) -AS complimentary to specific substrate
31
How does enzyme conc affect rate of enzyme controlled reactions
-Increasing enzyme conc., increases RoR -More enzymes= more available active sites -More successful E-S collisions and complexes -Until RoR plateaus
32
How does substrate conc affect rate of enzyme controlled reactions
-Increasing substrate conc, increases RoR -More successful E-S collisions and complexes
33
How does temperature affect rate of enzyme controlled reactions
-Increasing temp to optimum, increases RoR -Increase in kinetic energy -More successful E-S complexes and collisions -Increasing temp above optimum, rate of reaction falls -Enzymes denature; tertiary structure and active site changes shape -Fewer E-S collisions and E-S complexes, as substrate can no longer bind
34
How does pH affect rate of enzyme controlled reactions
-pH above/below optimum,RoR decreases -Enzymes denature; tertiary structure and active site changes shape -Fewer E-S collisions and E-S complexes, as substrate can no longer bind
35
Competitive inhibitors
-Similar shape to substrate -Compete to bind to AS so substrates cannot bind -Fewer E-S complexes -Increasing substrate conc reduces effect of inhibitor
36
Non- competitive inhibitor
-Binds to allosteric site -Enzyme tertiary structure/ changes shape so substrates can't bind to AS -Fewer E-S complexes
37
Function of DNA and RNA
DNA- holds genetic information RNA- transfers genetic info from DNA to ribosomes -Ribosomes are formed from RNA and proteins
38
The differences between DNA and RNA
-DNA nucleotides have the pentose sugar deoxyribose, whereas RNA nucleotides have the pentose sugar ribose -DNA nucleotides have the bases thymine, whereas RNA nucleotides have uracil instead -DNA has two strands, RNA is single stranded -DNA has H bonds, RNA doesn't -DNA is longer, RNA is shorter
39
Structure of DNA related to its function
-Double stranded; both strands can act as templates for semi-conservative replication -Weak H bonds between bases; can be unzipped for replication -Complementary base pairing; accurate replication -Many H bonds between bases; stable molecule -Double helix with sugar phosphate backbone; protects H bonds -Long molecule; stores lots of genetic info -Double helix; compact
40
Semi conservative replication
-DNA Helicase breaks H bonds between bases, unwinds double helix -2 strands act as templates -Free floating DNA nucleotides attract to exposed bases by specific complementary base pairing, H bonds are formed -DNA polymerase joins adjacent nucleotides by condensation, forms phosphodiester bonds -Replication is semi conservative- each new strands formed contains one original -Ensuring genetic continuity between generations of cells
41
How does DNA polymerase move along DNA antiparallel strands
-DNA polymerase is an enzyme with a specific AS which can only bind two substrate with complementary shape -Can only bind to the phosphate 3' end
42
Evidence for semi-conservative (Meselson and Stahl)
-Bacteria is grown in a nutrient solution contain heaving Nitrogen (15N) for several generations -Nitrogen is incorporated into bacterial DNA bases -Bacteria is transferred to a nutrient solution containing light Nitrogen (14N) and allowed to grow and divide twice -During this process, DNA moves from different samples of bacteria was extracted, suspended in a solution in separate tubes and spun in a centrifuge.
43
Structure of adenosine trisphosphate
-Ribose, a molecule of adenine, 3 phosphate groups -Nucleotide derivative -The structure of ADP= is the same as ATP, minus a phosphate
44
ATP hydrolysis
-Catalyses by ATP hydrolase -Inorganic phosphate releases can phosphorylate other compounds often making them more reactive
45
ATP condensation
-Catalysed by ATP synthase -Happens during respiration or photosynthesis
46
Properties of ATP
-ATP cannot be stored -ATP releasees energy in small, manageable amounts to reduce waste -Only one bond hydrolysed, to release energy
47
How does H bonding occur between water molecules
-Water is polar -Slightly negative O atoms attract slightly positive H atoms of other water molecules -So H bonds form
48
Water: High SHC explanation and importance
Polar so many H bonds between water→allow water to absorb a large amount of heat energy before its temp change -Good habitat for aquatic organisms -Organisms mostly made of water so helps maintains a constant internal body temp
49
Water: High LHE explanation and importance
Polar so many H bonds between water→allow water to absorb a lot of energy before breaking when water evaporates -Evaporation of small amount of water is an efficient cooling mechanism -Helping organisms maintain a constant body temp
50
Water: Cohesive explanation and importance
Polar so many H bonds between water→so water molecules tend to stick together -Columns of water don't break -Produces surface tension at an air water. surface so invertebrates can walk on water
51
Water: Solvent explanation and importance
Polar so can separate ionic compounds -Can dissolve other substance so water acts as a medium for metabolic reaction
52
Water:Metabolite explanation and importance
Reactive -Involved in condensation and hydrolysis reactions
53
Role of phosphate ions
Attached to other molecules as a phosphate group e.g: -DNA nucleotides, so nucleotides can join together and form phosphodiester bonds -ATP; bonds between these store/release energy
54
Role of Hydrogen ions
-Maintain pH levels in the body -Affects rate of enzyme controlled reactions
55
Role of Iron ions
-Component of Haem group of Haemaglobin -Transports Oxygen around body, O2 bind stocks it temporarily and forms Fe3+
56
Role of Sodium ions
-Co transport of glucose and amino acids across cell membranes -Involved in generating nerve impulses and muscle contraction

Biology (9 decks)

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