Module 6: Proteins Flashcards
1
Q
what elements are proteins made of
A
- carbon
- hydrogen
- oxygen
- nitrogen
2
Q
how much energy per gram does protein provide
A
4 kcal/g
3
Q
is supplying energy proteins primary function
A
no
4
Q
is there a storage form of protein
A
no
5
Q
what are proteins composed of
A
amino acids
6
Q
what are the components of an amino acid
A
- central carbon (C)
- amino group (NH3)
- carboxyl group (COOH)
- hydrogen group (H)
- r group (unique to each amino acid)
7
Q
how many amino acids are coded in the genome
A
20
8
Q
what is the most simple amino acid and describe its composition
A
- glycine
- r group is just an H
9
Q
define essential amino acids
A
must be acquired form our diet
10
Q
define nonessential amino acids
A
normally made by the body in adequate amounts
11
Q
define transamination
A
- transfer of amino group from one molecule to another to create an amino acid
- how nonessential amino acids are made
12
Q
give an example of transamination
A
pyruvate + glutamate = alphaketoglutinate + alanine
13
Q
what is the general equation for transamination
A
alpha keto acid (AKA) + amino acid (AA) = AKA + AA
14
Q
define conditionally essential amino acids
A
- must acquire from diet under certain conditions
- car accident, burns, etc.
15
Q
what type of bonds link amino acids
A
peptide bonds
16
Q
what is the first amino group in a protein structure known as
A
N terminus
17
Q
what is the last carboxyl group in a protein structure known as
A
C terminus
18
Q
describe how amino acids are attached
A
- OH of carboxyl group connects with H of amino group
- the OH and H become H2O and are given off when amino acids are linked
- C-OH + H-N = C-N + H2O
19
Q
define dehydration synthesis/condensation reaction
A
- two things combining and water being released
- occurs when combining amino acids
20
Q
what dictates protein function
A
shape
21
Q
describe the outcome of a correct amino acid sequence
A
predictable structure and function
22
Q
describe the outcome of an incorrect amino acid sequence
A
- structure changes
- error in function
- ex: sickle cell anemia
23
Q
why are protein structures curled
A
interactions between r groups of amino acids
24
Q
how can protein structure be changed
A
- heat
- acid
- enzymes
- agitation
- alcohol
- electrolysis
- salting
25
can denaturation be undone
no
26
does cold alter protein structure
- no
- preserves proteins
27
does denaturation change nutritional value
no
28
what are the functions of protein in the body
- hormones (insulin)
- growth/maintenance/repair
- body structure and blood
- fluid balance
- transport
- enzymes
- immune function (antibodies)
- acid base balance
29
where does water enter and exit from capillaries
between endothelial cells
30
how many red blood cells can fit through a capillary at once
1
31
what provides the pressure that moves blood through the body
heart
32
define hydrostatic pressure
- pressure against walls of vessels
- pushes water out of vessels and into tissues and lacteals
33
does your lymphatic system have a pump
no
34
define osmotic pressure
- pushes water into vessels
- due to concentration of proteins and electrolytes (sodium) in blood
35
what is the relationship between hydrostatic and osmotic pressure
opposing forces
36
does osmotic pressure or hydrostatic pressure win
- hydrostatic
- pushes more water out of cell than is pulled in
37
defien albumin
- protein solute in blood
- helps maintain fluid balance
38
define edema
- swelling
- water in tissues
- due to low blood albumin
39
why does low blood albumin cause edema
- low proteins in blood creates low osmotic pressure
- water isn't being brough back into blood vessels
- water stays in tissues causing swelling
40
what is the pH range of the body
7.35-7.45
41
how do proteins maintain acid base balance
- act as buffers
- neutralization of acidic and basic conditions
42
is the body more acidic or more basic
more basic
43
define antigen
- foreign substance that enters the body and triggers an immune response
- virus, bacteria, splinter, etc.
44
what is the body's first barriers against immune invaders
- skin
- mucus
45
define antibodies
- proteins produced by immune system in response to antigen
- y-shaped
- attach to antigen and mark for elimination
46
describe how your immune cells protect against antigens
- immune cells (like macrophages) engulf an antigen and take part of it to B cells
- the B cells then make antibodies from the antigen
47
describe enzymes
- protein scissors
- speed up chemical reactions
- strings of 100 to 1000 amino acids
48
what are some causes of deficiencies in enzymes
- genetic: error in metabolism
- non genetic: illness, inadequate nutrition, medications
49
define hormones
messengers that help regulate the various systems and functions of the body
50
what are hormones made out of
- lipids
- proteins
51
what is an example of proteins transporting substances across cell walls/membranes
sodium potassium pump
52
what is the purpose of the sodium potassium pump
maintain electrical potential around the cell membrane
53
what is an example of proteins transporting nutrients through the bloodstream
retinol binding proteins
54
what is retinol
vitamin A
55
what are two ways that proteins can be used for transport
- across cell walls/membranes
- through bloodstream
56
does albumin contribute to hydrostatic or osmotic pressure
osmostic
57
what is the purpose of proteins on the outside of lipoproteins
communication between lipoproteins and other body tissues
58
what is the least efficient function of proteins
energy production
59
is there a storage form of protein
no
60
does 100 cal of protein = 100 cal of carbs
no
61
when and how does the body use protein for energy
- when: carb and fat intake is low
- how: breaks down muscle and uses amino acids for energy
62
what is included in protein turnover
- protein synthesis
- protein breakdown
63
what protein has the highest turnover rate
collagen
64
what does protein synthesis require
presence of essential amino acids in adequate amounts
65
define limiting amino acids
present in low amounts relative to the body's needs
66
what happens during protein breakdown
free amino acids become part of the amino acid pool
67
is your amino acid pool usually low or high
usually very low
68
define deamination
- removal of an amino group
- removal of nitrogen
69
why is deamination essential
required for elimination of excess amino acids
70
where does deamination primarily occur
liver
71
what happens during deamination
the amino group (NH3) is converted to urea which then gets excreted in urine
72
define nitrogen balance
- nitrogen consumed vs. nitrogen excreted
- basis of many nutrition recommendations
73
when would you have a positive nitrogen balance
eating enough or excess protein
74
when would you have a negative nitrogen balance
eating not enough protein
75
how many times must deamination be done to make one urea
twice
76
what is the general equation for deamination
NH3 + CO2 = urea + water
77
when does a positive nitrogen balance occur
- growth
- recovery from illness
- pregnancy
78
when does a negative nitrogen balance occur
- AIDS
- cancer
- starvation
- low calorie diets
79
define complete/high quality proteins
- provides all essential amino acids
- easily digested and absorbed
80
what are sources of complete/high quality proteins
- animal products (meat, dairy)
- soy
- quinoa
81
what are the 2 plant based complete proteins
- soy
- quinoa
82
define protein digestibility-corrected amino acid score (PDCAAS)
- value assigned to proteins that accounts for protein quality and digestibility
- based on scale of 0-100
83
define incomplete proteins
do not contain all essential amino acids
84
examples of incomplete proteins
- legumes
- grains
- vegetables
85
define complementary proteins
foods that contain all essential amino acids when combined
86
what is a common example of complementary proteins
rice and beans
87
define supplemental proteins
- additional source of protein for specific populations
- vegetarians, highly active people, underweight people
88
does soy contain cholesterol
no, it is plant-based
89
what are health benefits associated with soy consumption
- protection against certain cancers and CVD disease
- prevention of bone loss
90
what is the nutritional composition of soy
- complete protein
- low in saturated fat and cholesterol
- B vitamins, calcium, potassium, vitamin A, iron
91
what is another bioactive compound found in soy
- isoflavones (a phytochemical)
- act as phytoestrogens
92
what is the RDA for protein
0.8g per kg of body weight
93
what is the AMDR for protein
10-35%
94
why might protein needs increase
- injury
- illness
- pregnancy
- competitive athletes
95
define vegan
omit all animal products
96
define lacto-vegetarians
include dairy
97
define lacto-ovo-vegetarians
include dairy and eggs
98
define pescatarians
include seafood
99
why do people choose to be vegetarians
- treatment of animals
- hormones and antibiotics
- environmental impact
- health
- religion
100
what are potential health benefits of vegetarianism
- low risk of heart disease
- low rates of obesity
101
what vitamin do we get mostly from animal products
vitamin B12
102
what are nutrients of concern for vegetarians
- vitamin B12
- zinc
- iron
- calcium
- vitamin D
- protein
103
define protein energy malnutrition (PEM)
disorder that occurs with inadequate protein and/or energy consumption
104
what would your nitrogen balance be if you had protein energy malnutrition (PEM)
negative nitrogen balance
105
what is the most common nutrient deficiency in hospitals and nursing homes in the US
protein energy malnutrition (PEM)
106
who is most at risk for protein energy malnutrition (PEM) internationally
infants and young children
107
what is the most lethal form of malnutrition
protein energy malnutrition (PEM)
108
what are the two types of protein energy malnutrition (PEM)
- marasmus
- kwashiokor
109
define marasmus and its causes
-condition of starvation characterized by emaciation, or skeletal appearance
- causes: inadequate protein and calorie intake
110
define kwashiokor and its causes
- characterized by swollen appearance, especially in the abdomen from fluid in tissue caused by decreased osmotic pressure
- causes: low protein intake, altered hut bacterial populations
111
who is often seen having kwashiokor
children being weened from breast milk
112
are high protein diets associated with longevity
- no
- survival and reproduction
113
what are the health benefits of excess protein
weight loss/fat loss
114
what are the health risks of excess protein
- increased risk of certain types of cancer
- kidney disease and kidney stones
- increased risk of heart disease (if diet is high in saturated fats)
