Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

home ec > protein > Flashcards

protein Flashcards

(70 cards)

Start Studying
1
Q

what elements make up protein

A

carbon, hydrogen, oxygen, nitrogen

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

what is the smallest unit of a protein

A

amino acid

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

what is created when amino acids are joined by peptide links

A

a polypeptide chain

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

what are the 5 components of an amino acid

A

an amino group (NH2), a carboxyl group(COOH), a central carbon, a single hydrogen and a variable group that changes

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

how many essential and non essential amino acids are there

A

20, 10 essential and 10 non-essential

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

how are essential amino acids obtained

A

through food as the body cannot make them.

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

how many essential amino acids do children and adults require

A

10 for children and 8 for adults

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

name three amino acids

A

lysine, leucine and isoleucine

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

what are the two essential amino acids for children

A

histidine and arginine

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

how are non essential amino acids obtained

A

they are manufactured in the body

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

name three non essential amino acids

A

alanine, cysteine and serine

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

what results when two amino acids join together

A

peptide links are formed and there is a loss of water (condensation reaction)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q
A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what occurs in the formation of a peptide link

A

the COOH group of one amino acid loses an OH and the NH2 group of another loses a H which form H2O that is lost. the remaining CO-NH bond, the new molecule is a dipeptide.

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

how many amino acids join together to make a polypeptide chain

A

20

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

how many amino acids join together to make a protein

A

50

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

what is the reverse of the condensation reaction

A

hydrolysis

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

what occurs during hydrolysis

A

the addition of water and enzyme action that occurs during digestions when proteins are broken back down into amino acids

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

what is the primary structure of protein

A

the order or sequence of amino acids in protein chains

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

what is the secondary structure of protein

A

involves the folding of the primary structure into two dimensional shapes, polypeptide chains either fold in on themselves or crosslink with another chain.

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

what is the purpose of protein secondary structure

A

gives proteins their unique properties eg: elasticity of gluten

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

what are the two main types of cross links

A

disulfide and hydrogen

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

what is a disulfide bond

A

occurs when two suflurs from two amino acids join together from either a single polypeptide or two different chains

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

what is a hydrogen bond

A

occurs when the hydrogen from the amino group joins with an oxygen of another amino acids carboxyl group

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
what is the tertiary structure of protein
involves the folding of the secondary structure into two or three dimensional shapes
26
what is the fibrous shape of protein
polypeptide chains are arranged in straight, spiral or zigzag two dimensional shapes
27
what are the properties of fibrous shape protein
insoluble in water and not easily dentaured
28
what are examples of fibrous shape protein
gluten, elastin and collagen
29
what do globular shape proteins look like
polypeptide chains are arranged in spherical three dimensional shapes
30
what are the properties and examples of globular shape proteins
soluble in water and easily dentaured, examples: ovalbumin and lactalbumin
31
what is a conjugated protein
when a protein combines with a non protein molecule
32
what are the two subgroups of plant protein
glutenins and prolamines
33
33
what are the sub groups of conjugated proteins
lipoproteins(lecithin) and phosphoproteins (caseinogen)
34
what is biological value of protein
a measure of protein quality that is determined by the number of essential amino acids
35
where are HBV proteins found
mostly animal sources besides soya beans
36
what are LBV proteins and where are they found
they lack one or more essential amino acids and are mostly found in plant sources besides gelatin
37
what is an example of food with 100% biological value
eggs
38
what is the supplementary role of protein
when two LBV foods are eaten together to provide all the essential amino acids
39
what is an example of supplementary role of protein
bread lacks lysine but is high in methionine whereas beans are lacking methionine but are high in lysine
40
what are the properties of protein
denaturation, elasticity, maillard reaction, solubility, gel formation and foam formation
41
what is denaturation of protein
involves the unfolding of a protein chain which is irreversible, it is brought about by physical or chemicals means like heat chemicals, mechanical actions and enzymes. It results in the hardening or setting of protein foods known as coagulation
42
what is a culinary application of denaturation of protein by heat
albumin in egg white coagulates at 60 degrees and the colour changes from transparent to an opaque and it becomes a solid
43
what is a culinary application of denaturation of protein by chemicals
Vinegar based marinade tendersies meat by denaturation
44
what is a culinary application of denaturation of protein by mechanical action
the beating of eggs to make meringues
45
what is a culinary application of denaturation of protein by enzymes
the enzyme rennin in rennet causes caseinogen in milk to coagulate during cheese making forming curds and whey
46
what is a culinary application of elasticity of protein
gluten makes yeast dough elastic enough to trap CO2 gas produced by yeast helping it to rise
47
what is a culinary application of the maillard reaction of protein
shortbread biscuits
48
what is the maillard reaction
the non enzymic browning of food due to a reaction between amino acids and sugar under dry heat. it produces an attractive brown colour and a crust with an appetising flavour
49
what is a culinary application of solubility of protein
moist heat tenderises meat by converting collagen to gelatine eg during stewing
50
what is a culinary application of gel formation of protein
setting cheesecakes and jelly sweets
51
what is the gel formation of protein
when collagen is heated and converted to gelatine which can absorb large amounts of water which becomes trapped as the protein chains are heated, this forms a sol which forms a gel
52
what is the foam formation of protein
when an egg white is whisked, protein chains unfold and air bubbles form , the protein traps air, creating a foam which is temporary until heated
53
what is a culinary application of foam formation of protein
meringues
54
what are the effects of dry and moist heat on proteins
coagulation, colour changes and overcooking causes protein to be indigestible
55
what are the effects of dry heat only on proteins
maillard reaction
56
what are the effects of moist heat only on proteins
tenderising meat
57
what are the biological functions of structural proteins
production of cell membranes, muscle tissue and skin, cell repair and replacement and growth
58
what are the biological functions of physiologically active proteins
production of hormonal proteins, enzymes, antibodies, blood proteins and nucleoproteins
59
what are the biological functions of nutrient proteins
provide the body with essential amino acids and excess are use as an energy source when carb and fat reserves are used
60
what is a result of a deficiency of structural proteins
retarded growth and delayed healing
61
what is a result of a deficiency of physiologically active proteins
body organs and systems malfunction, easily infected
62
what is the recommended daily allowance of protein
0.75g per kg of body weight
63
how many kcal in 1 g of protein
4 kcal
64
what occurs in the stomach to break down proteins
HCL denatures proteins, rennin breaks down caseinogen to casein and pepsin breaks down proteins into peptones
65
what occurs in the pancreas to break down proteins
pancreatic juice is secreted into the duodenum which contains trypsin which breaks down peptones into peptides
66
what occurs in the small intestine to break down proteins
the ileum secretes intestinal juice which contains peptidase that breaks down peptides into amino acids which can now be absorbed and utilised
67
what is the order of breakdown of proteins
protein->peptones->peptides->amino acids
68
what happens to amino acids when they enter the liver
they are used to maintain and repair liver cells and passed into the bloodstream and body tissues to form new cells, hormones, enzymes and antibodies
69
what is deamination
the process by which excess amino acids are broken down in the liver, the amino group is converted to ammonia then urea and excreted and the carboxyl group is oxidised to produce heat and energy

home ec (63 decks)

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