Biological Molecules and Enzymes Flashcards

1
Q

What ratio is hydrogent to oxygen in carbohydrates

A

2:1

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

What is molecular formula of 3 main hexose sugar?

A

C6H12O6

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

Name 3 types of hexose sugar?

A

Glucose
Galactose
Fructose

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

What is difference between alpha and beta glucose?

A

Alpha has glucose above
Beta has glucose below

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

What is main 3 disaccharides and what they consis of?

A

Maltose, 2 glucose

Sucrose, 1 glucose and 1 fructose

Lactose, 1 glucose and 1 galactose

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

Name and describe reaction joining 2 monomers?

A

Condensation reaction

It form chemical bond between 2 molecules releasing 1 water molecule as byproduct

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

Name and describe reaction breaking a dimer or polymer?

A

Hydrolysis

Chemical bond between 2 molecules is broke by instertion of 1 water molecule

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

Describe test for reducing sugar?

A

Add benedicts solution to sample

Boil for 5 minutes

A brick red/orange colour if present

If not solution remain blue

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

Describe test for non-reducing sugar?

A

First test sample with benedicts solution to confirm negative results

Then boil sample with dilute acid

Then cool then add sodium hydroxide solution to neutralise it

Then add benedicts solution and boil

If non-reducing sugar, now red brick colour shoud appear

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

What is example of non-reducing sugar?

A

Sucrose

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

What is 4 main similar and different properties of cellulose, starch and glycogen?

A

They differ in num and arrangement of glucose

They function as storage or structural molecules

They are non-reducing

They are unsweet

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

What is cellulose?

A

Consist of beta glucose

Fromed by 1-4 glycosidic bond so every beta glucose invert

Long, straight chain

Hydroxyl group form hydrogen bond with other chain hydroxyl group called microfibril

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

What is macrofibrils?

A

Bundle of microfibril

One macrofibril goes in same direction

Succesuve layers are in different direction

They are interwoven and embedded in matrix to provide rigidity

Gaps between layer allow fully permeable cell wall

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

What is purpose of cellulose?

A

Rigid, structural support preventing cell from bursting

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

What is starch?

A

Storage used for respiration made by alpha glucose

Found in starch grain of plant

Amylose and amylopectin

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

What is properties of starch?

A

Long chain of alpha glucose

Compact, helical shape due to hydroxyl group forming hydrogen bond

Amylopecting is branched but amylose is straight

Amylopectin has 1-4 and 1-6 glycosidic bond and amylose only 1-4 glycosidic bond

Insoluble so osmotically inactive

Too large to cross cell membrane but compact

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

Name and describe test for starch test?

A

Iodine test

Add few drops of iodine to sample

If starch is present blue/black colour appear

If no starch remains orange/yellow

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

What is glycogen?

A

Energy store in animal and fungi

Same properties as starch but more branched

Mostly liver and muscle tissue

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

What is 2 types of lipids?

A

Triglycerides and phospholipid

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

What is properties of triglycerides?

A

Made of 3 fatty acid and 1 glycerol

Insoluble so osmotically inactive

Soluble in various solvent e.g. alcohol but water

Formed by condensation reaction

Has ester bond

Acts as structure and enery storage

Release twice as much energy than carbohydrates

Higher portion of H

Can be saturated or unsaturated

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

Is saturated solid or liquid?

A

Usually fat

Unsaturated usually oil
As less surface contact of molecule due to bending

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

Describe and name test for lipids?

A

Emulsion test

Add ethanol to sample

Shake so lipid dissolve

Then add water and mix

White emulsion should appear as indication

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

What is properties of phospholipid?

A

Made of glycerol, 2 fatty acid and 1 phosphate

Joined by condensation reaction

Polar hydrophilic head is phosphate

Non-polar hydrophobic tail is fatty acid

24
Q

Why is phospholipid important?

A

Cell membrane is formed mainly by phospholipid bylayer

Also form micelles used in lipid digestive absorbtion

25
What element does amino acid contains?
C,H, O and N Sometimes S
26
Properties of amino acid
Monomer of polypeptide All have amine group, a carboxylic group, H attached to C but differ in R group Theres 20 different R group Peptide bond joined by condensation reaction Condensation reactionn is between carboxylic and amine group
27
2 types of enzymes hydrolysing peptide bond and how they differ?
Exopeptidases - hydrolyse ends of polypeptide chain Endopeptidases - hydrolyse internal of polypeptide chain
28
Primary structure
Sequence of amino acids in the polypeptide chain, determines the specific shape of the protein
29
Secondary structure
H-bond caused by C=O and N-H groups They can be alpha helix or beta pleated sheet
30
Tertiary structure
Ionic, H, disulfide bridge and hydrophobic bonds
31
Quaternary structure
More than 1 peptide chain Held by same bonds as tertiary structure Maybe assosiated with non-protein/prosthetic groups(e.g. Fe2+)
32
Where does H-bond occurs in amino acid?
May form by C=O and N-H groups Occurs within same chain May also form between R groups of polar amino acids
33
# ***Check*** Where does Ionic bond form in amino acid?
Form between + and - charged side chain of bacis and acidic amino acids respectively
34
Where does Hydrophobic region happens in amino acid?
Hydrophobic side chains exclude H2O and attracted to each other
35
Where does Disulfide bridge form in amino acid?
Oxidation reaction forms it between 2 cystine amino acid
36
2 types of protein?
Fiburous and globural
37
Explain what is fiburous proteins and e.g.?
Structural function Insoluble and simple tertiary and quaternary structure made of long parallel chain Provide strenght and flexibility Collagen and keratin
38
Explain what is globural protein and e.g.?
Highly folded and coiled polypeptide chain forms specific tertiary structure Soluble in water Insulin, antibodies, enzymes, receptor
39
What breaks hydrogen bonds?
pH, temperature
40
What breaks ionic bonds?
pH
41
What breaks disulfide bridges?
Reducing agent
42
What is 2 methods to change shape of protein?
Heavy metal binding Denature
43
Describe biochemical test for protein?
Add biuret agent to sample If purple protein present If remains blue no protein present
44
Define enzymes?
Globural protein that acts as biological catalyst with specific active site due to specific tertiary structure
45
How does enzymes work?
Lower activation energy So rate of reaction increase So more easier for reaction to take place at low temperature
46
Name and describe 2 hypothesis related to Enzymes substrate complex formation?
Lock and key hypotheis: Only substrate with complementary shape to substrate form ESC Enzymes remains unchanged at end Induced fit hypotheis: Enzymes have more flexibility as change shape slightly Substrate change enzyme active site, and may stain on bonds of substrate so easier hydrolysis Active site allow molecules to come closer so easier condensation
47
List limiting factor for ESC formation?
Enzyme concentration Substare concentration Temperature pH
48
How does enzyme concentration effect ESC?
If more enzyme conc, then more active site available More likely for substrate to collide So rate increase If substrate does not limit rate
49
How does substrate concentration effect ESC?
More likely for enzymes to collide Then rate levels off as they saturare active site So enzyme concentration is limiting factor
50
How does temperature affect ESC?
More kinetic energy So more collision so more ESC Optimum temperature leads to highest rate Hydrogen and ionic bond break if too high. leading to denaturation This alter active site shape So no ESC
51
Temperature coefficient
Rate of reaction at (x+10)/rate of reaction at x
52
How does pH effect ESC?
pH different from optimum causes denaturation As alters ionic charges of acidic and basic groups So shape of active site change No longer ESC formation
53
Name 3 types of enzyme inhibitor and how they work?
Competitive inhibitor Inhibitor has similar shape to substrate So competes with substrate to bind with active site Reduced by inc substrate concentration Non-competitive inhibitor Not similar in shape to substrate Bind to allosteric sire Alters tertiary shape and so active site shape Some would not be able to form ESC or would bind but product dosent form End-product inhibition When end product inhibits It happens when accumulate So it switch off reaction as builds up Self-regulatory, so if product decrease switch on Example of negative feedback Example is glycolysis
54
What is Immobilised enzymes?
Allows to reduce cost and inc efficiency in commercial use Traps enzymes to plastic support, so recovered easier after reaction So enzymes can be re-used Also make enzymes more stable by restricting abillity to change shape or denature No contamination occurs
55
Example of enzymes that become stable by immobilising them?
Glucose isomerase Stable for a year at 65 degrees celsius in immobilised state but denature whitin few hours at 45 degrees celsius without
56
Physical bonding process in immobilisation?
Adsorbed onto an isoluble matrix, e.g. collagen Held inside a gel, such as silica gel Held within a semi-permeable membrane e.g. polymer microsphere Trapped in a micro-capsule e.g. alginate beads
57
Chemical bonding in immobilisation process?
Enzymes can be chemically bonded to the support medium E.g. use glutaraldehyde to binf it to cellulose fibers Since enzymes are covalently bonded, enzymes activity is high Difficult process