Brainscape's Knowledge GenomeTM

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


See full index

chemistry 3/4 > food > Flashcards

food Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Chemistry flashcards Periodic Table flashcards Chemistry 101 flashcards Organic Chemistry 101 flashcards
1
Q

what are core food molecules and biomolecules

A

carbohydrates
proteins and enzymes
fats and oils (triglycerides)
vitamins

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

carbohydrates

A
  • Cx(H2O)y
  • provide a source of energy, way of storing energy, structural material
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

carbohydrates general structure

A
  • dissacharides or polysaccharides are joined with a glycosidic link / ether group
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

lactose monomers?

A

galactose and glucose

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

sucrose monomers?

A

fructose and glucose

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

maltose monomers?

A

2x glucose

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

glucose vs fructose difference

A

glucose= in fischer projection there is an aldehyde group
fructose= ketone group on 2nd C

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

determining mass of saccharide

A

180 x number of glucose = ___x__
18x( no. glucose- 1) =___y___
t/f x-y

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

polysaccharide examples

A

starch - amylose and amylopectin
glycogen (alpha glucose)
cellulose (beta glucose)

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

starch

A
  • energy storage components of plants
    -composed of alpha glucose
    -two forms - amylose and amylopectin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

amylopectin

A

-crosslink bw glucose molecules - reaction bw OH groups on C1 and C6 sections
-less effective packing and decrease attraction bw OH groups - weaker H bond - high GI

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

amylose

A
  • linear polymer that properly packs effectively - strong attraction to OH groups - low GI
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

amylopectin vs amylose

A

branching affects ability to breakdown
-amylopectin to break down faster

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

glycogen

A

-energy storage structure in humans & animals
-alpha glucose
-highly branched
- convert glucose into glycogen and stored in liver& muscle cells

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

cellulose

A
  • structural material found in plants
    -formed from beta glucose
  • tightly pack together - strength as plant fibre
  • body = unable to break down & acts as dietary fibre
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

artificial sweeteners

A
  • similar sized to many common sugars but are significantlly sweeter than sugars
  • require lower energy/ calorie diets to obtain same amount of sweetness
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

aspartame

A

outcome of a reaction between aspartic acid, phenylalanone and methanol - is an artificial sweetener

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

energy carbohydrates

A

most common source of energy - hydrolysed to form glucoes which undergoes respiration to form energy

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

cellulose - indigestible carbs

A
  • human body lacks necessary enzyme to catalyse the reaction
  • considered a dietary fibre bc helps food pass through in bulk amounts and decreases risk of constipation, cancers etc.
  • bodies have system to break it down but it passes through body before broken down into any nutritional value
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

intolerances eg. lactose

A

lack sufficient amount of the enzyme lactase to hydrolyse the lactose sugar
-side effects - discomfort, bloating ,cramps, diarrhoea

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

GMI definition

A

how quickly glucose is released in the bloodstream after consuming food
- low GI is slower than high GI

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

HIGH GI HAS WHAT

A

AMYLPECTIN

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

LOW GI HAS WHAT

A

AMYLOSE

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

diabetes

A
  • type 1 - doesnt produce necessary insulin
    -type 2 - cannot produce quickly enoigh to match the release of glucose into the blood
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

fats and oil (triglycerides)

A
  • ESTERS
    -contain CHO
  • formed in condensation reaction bw glyecrol and 3 fatty acids and forms triglyceride and water
  • large relatively non polar - low solubility
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

unsaturated - mono or poly

A

C to C double bonds

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

saturated formuls - fatty acid

A

CnH2n+1COOH

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

monounsaturated fatty acid general form

A

CnH2n-1COOH

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

essential fatty acids

A

-fatty acids that the body cannot synthesise
- obtained from food / diet - omega 3 or 6 and need a good dietary balance

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

nonessential fatty acids

A
  • body is capable of synthesising FA
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

omega 6 benefits

A

known to increase blood pressure, immune response and inflammation

32
Q

omega 3 benefits

A

heart healthy effects

33
Q

omega 3 or 6

A

depends on where the first c to c double bond is from the omega end (opposite COOH region)

34
Q

trans fats

A
  • unsaturated that are artificially produced - in hydrogenation (Ni catalyst and 15deg)
    -resisted rancidity and desirable MP
35
Q

rancidity - possible reactions?

A

-oxidative = O reacts near double bond
- microbial = bacterial action
- hydrolytic= hydrolysis to fatty acid and glycerol

36
Q

rancidity

A
  • fats and oils deterioate over time
  • unsaturated fats are less stable bc more succeptible to oxidative rancidity
  • deterioate food or smell
37
Q

oxidative rancidity problems

A

lead to formation of unpleasant smelling and potential harmful short chain aldehydes and ketones - unpleasant smells & flavours
- most common = autooxidation

38
Q

how are vitamins distinguished

A

water soluble or fat soluble

39
Q

water soluble vitamins

A
  • consumed regularly
  • high proportion of OH groups that form H bonds with water and dissolve - pass through body quickly
40
Q

fat soluble vitamins

A

long hydrocarbon chains - low OH groups so stronger dispersion forces compared to few H bonds - absorbed by the body

41
Q

methods to slow rancidity

A
  • vacuum packaging
  • fill containers to the lid
  • store food in dark and cold
  • antioxidants
42
Q

antioxidants

A
  • eg. vitamin C
  • natural or synthetic and will slow down oxidation and prevent food from spoiling
  • donate an e- to free radicals in order to interupt propagation of free radicals - increase rancidity
43
Q

vitamins essential or not

A

non essential - vitamin D
essential - other vitamins

44
Q

vitamins

A
  • perform variety of vital roles including action as a coenzyme, aiding the immune system or preventing hamrful chemical reactions (antioxidant)
45
Q

difference bw carbohydrate and triglyceride in terms of structure

A

fatty acid has only 2 oxygen atoms whereas carbohydrates have lots of oxygen

46
Q

amino acids

A

CHONS

47
Q

zwitterions

A

dipolar ions
- have no overall net charge
- contains a negative and positive charge/ region
-exist at neutral pH (7)

48
Q

in basic environment a zwitterion

A

gains H+ on the N region - net negative charge

49
Q

in acidic environment a zwitterion

A

forms a NH3+

50
Q

what links a dipeptide

A

amide or peptide linkages

51
Q

primary protein structure

A
  • amino acid sequence in the peptide /protein chain
  • strong covalent bonds linking each aa at amide link
52
Q

secondary structure protein

A
  • forms H bonds with different sections of the protein chain -H attached to N and the O attached to C = H bonds
  • primary structure folded into alpha helix or beta pleated sheets
53
Q

tertiary protein structure

A
  • unique 3d shape of the protein (globular)
    -this determines its unique function
  • driven by the side chain/ R groups
    -bonds that keep structure intact include covalent bonds, dp-dp, H bonds etc.
54
Q

quaternary protein structure

A
  • 2 or more polypeptides joined together
    eg. haemoglobin
55
Q

digestion of proteins

A
  • aa are absorbed in the bloodstream and used to build up new protein
    -aa not used are broken down in liver (deamination) where NH2 is converted into ammonia which is converted to urea and excreted or used to synthesise other proteins
  • remainder proteins composed of CHO=converted to glucose(energy), fat(storage) or aa
56
Q

hydrolysis of protein

A

CHANGE PRIMARY STRUCTURE
covalent bonds are broken in presence of water and specific enzymes

57
Q

denaturation of proteins

A
  • change in 3D structure (tertiary) or function of molecules like proteins at extreme pH or temperature
  • disrupt R groups
    -can be reversible and irreversible depending on protein+ ability to reconfigure its 3D shape
58
Q

enzymes - role and function

A
  • biological catalysts
    -catalyses chemical reactions in the body which is necessary to sustain life otherwise metabolic cellular processes= too slow
  • provides alternate reaction pathway that lowers the activation energy
  • can be measured by noting ROR
59
Q

enzyme action

A
  • reactant/substrate binds to enzyme at active site - it will be S+C in terms of shape and charge
  • not consumed
60
Q

lock and key enzyme model

A

substrate perfectly fits into enzyme , like a lock
- after successful binding forms an ESC and catalyse reaction = catabolism or anabolism

61
Q

enzyme induced fit

A
  • shape of the substrate X perfectly complimentary to shape of as.
  • to overcome this as adjusts to become S+C to substrate
  • afterwards the as. returns to its original shape/ remains unchanged
62
Q

enzyme activity definition

A

amount of substrate converted to product per unit time

63
Q

denaturation of enzymes

A

-temp - increase KE makes molecules vibrate more rapidly so H bond , interaction bw R groups and arrangement of protein is disrupt
-pH -change the 3D shape of protein

64
Q

enzyme - enantiomers

A
  • only catalyses a reaction w one enantiomer bc the as is S+C - different arrangement of atoms - specificity
65
Q

coenzymes

A

-do not catalyse a reaction
-temporarily bind to as of enzyme as they are modified to suit the shape of the substrate
- serve as a carrier of groups of atom/ e-

66
Q

calibration factor electrical

A

CF= VxI xT
————-
delta T

67
Q

calibration factor chemical

A

CF = E/ delta T

68
Q

poorly insulated calorimeters need what

A

to extrapolate data back to time calorimeter was turned on

69
Q

what is a condition for bomb calorimetry

A

high pressure to ensure reaction goes to completion

70
Q

calorimetry

A

method where the heat released or abosrbed is measured

71
Q

random errors for calorimetry

A
  • not all food combusted
  • incomplete combustion
  • temperature change = inaccurate
72
Q

systematic error for calorimetry

A
  • calirometer calibrated incorrectly
  • measurement to calibrate eq. = incorrect - affect energy calc.
73
Q

types of calorimeter

A

solution and bomb

74
Q

bomb calorimetry

A

-measures HoC of chemical reactions that involve gaseous reactants or products
-exothermic
-measures heat content of fuels and foods

75
Q

solution calorimetry

A
  • calculates energy transferred in a chemical reaction
  • measure heat of solution/neutralisation

chemistry 3/4 (8 decks)

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