Week 6 Flashcards
1
Q
What is the only rock that humans eat?
A
salt
2
Q
Latin word for salt
A
sal
3
Q
The word salary comes from the fact that they used to pay people with salt… so a person would be
A
“worth their salt”
4
Q
What is one of the most important historical uses of salt?
A
preservation of food
5
Q
sodium is a major positive ion in bodily fluids, so its concentration determines the total concentration of solutes, called
A
osmolarity
6
Q
through a process called ____, water moves across the semipermeable membrane from an area of low solute concentration to an area of high solute concentration
A
osmosis
7
Q
saltiness is a taste produced primarily by the presence of
A
sodium ions
8
Q
What other ions taste salty?
A
other alkali metal ions but the further they are from sodium the less salty they are
9
Q
What is the saltiness index of sodium chloride (NaCl)?
A
1
10
Q
What is the saltiness index of potassium chloride (KCl)?
A
0.6
11
Q
These ions cause the basic salty taste
A
cations
12
Q
These ions modify the basic salty taste
A
anions
13
Q
These two cations produce only salty taste
A
sodium and lithium
14
Q
These cations produce both salty and bitter tastes
A
potassium and other alkaline earth cations
15
Q
This anion is the least inhibitory to salty taste
A
chloride anion
16
Q
This anion doesn’t contribute any taste
A
chloride anion
17
Q
These anions suppress salty taste and also contribute anionic tastes to food products
A
citrate
18
Q
What are the 6 ways which salts can be formed by chemical reaction?
A
19
Q
What salt gives salty taste?
A
sodium chloride
20
Q
What salt gives sweet taste?
A
lead diacetate
21
Q
What salt gives sour taste?
A
potassium bitartrate
22
Q
What salt gives bitter taste?
A
magnesium sulfate
23
Q
What salt gives umami or savory taste?
A
monosodium glutamate
24
Q
These salts are non-volatile and often odorless
A
strong acids and strong bases OR “strong salts”
25
These salts may smell like conjugate acid like vinegar or conjugate bases like ammonia
weak acids and weak bases OR "weak salts"
26
Taking too much salt has been associated with ____ which can damage the heart and blood vessels and increase the risk of heart attack and stroke
high blood pressure
27
Consuming a lot of salt may cause more ___ to excreted from the urine. So people on a high-salt diet will have to take more of this to make up for what is lost in the urine.
Calcium
28
What painful thing can a high salt diet lead to?
kidney stones
29
What are some negatives when you remove salt from your diet?
1. lose saltiness
2. release bitterness masked by salt which reduces sweetness
3. reduce desirable aroma
4. reduce desirable mouth feel
5. may stimulate production of renin which impacts water balance in the body
30
What is the WHO recommendation for salt per day?
2000 mg/day/person
31
What is the estimated salt intake for Korea, Japan, China and the US
32
What are 6 health benefits of salts?
1. flavour
2. digestion
3. lubricates tissues
4. liquefies mucous
5. maintains mineral balance
6. aids in elimination of wastes
33
What are the 2 adverse effects of high salt intake?
1. high blood pressure
2. cardiovascular diseases
34
What is the adverse effect on health as a result of too little salt?
dizziness/electrolyte disturbance which can cause neurological problems
35
What are the 3 impacts of reducing blood pressure through dietary sodium?
reduction in
1. myocardial infarction (5%)
2. strokes (13%)
3. heart failure (17%)
36
How much money would be saved in the US and Canada if the health care costs associated were reduced do to lower salt intake?
1.7 billion --> Canada
18 billion --> USA
37
How can salt intake lead to obesity?
high salt = increase thirst and fluid consumption --> excess calorie and beverage consumption
38
Where does most salt in our diet come from?
restaurant/processed food (77%)
followed by 12% naturally in foods
and 11% added at the table or in cooking
39
What can be used as a preventative measure against a goiter?
iodized salt
40
How much sodium is in iodized salt?
5 mg/kg of sodium-, potassium-, or calcium-iodide
41
What are 4 examples of salt substitutes?
1. potassium chloride
2. potassium lactate
3. seaweed
4. glutamic acid
42
What is the most common salt substitute that is mixed 50/50 with NaCl?
KCl (potassium chloride)
43
What is the salt perception mechanism?
entry of H+ and Na+ ions through ENaCs (epithelial sodium channels)
44
In the ENaC hetomer, how many subunits are there?
1. alpha
2. beta
3. gamma
4. delta
45
How many transmembrane domains does ENac have?
two
46
Is ENaC encoded by a separate gene?
Yes
47
What is the ENaC strongly inhibited by
amiloride
48
What are the 4 subunits which form the Human ENaC?
1. alpha
2. beta
3. gamma
4. delta
49
What are the 3 subunits which form the mouse ENaC?
1. alpha
2. beta
3. gamma
50
This drug is used as a potassium-sparing diuretic which is used in the management of hypertension and congestive heart failure
amiloride
51
Describe the Amiloride-Sensitive (AS) or "Low salt" pathway
1. selective Na+ (and Li+ ions)
2. sensitive to lower concentrations of salt (~10-30 mM NaCl)
3. mediated by ENaC channels
52
Describe the Amiloride-Insensitive (AI) or "high salt" pathway
1. responds to a broad range of cations
2. higher threshold of activation (~100 mM NaCl)
3. receptor unknown
53
What are the 3 effects of amiloride on salty taste responses in rodents?
1. suppresses responses in afferent gustatory nerves
2. increases detection threshold
3. impairs discrimination between Na and K
54
What are three physiologically distinguishing features of amiloride insensitive salt taste?
1. high threshold of activation (>100 mM NaCl)
2. anion inhibition
3. responding to a broad range of cations, including divalent cations
55
Recent evidence suggests that these have their own taste receptor
fatty acids
56
oleogustus
"fat taste"
57
What is oleogustus triggered by?
nonesterified fatty acids (NEFA)
58
What are the 3 acids of oleogustus/"fat taste"?
1. oleic acid
2. linoleic acid
3. 9-decenoic acid
59
In the Western diet, about how much of our daily energy is composed of lipids?
40%
60
What 4 things can high fat contribute to?
1. obesity
2. type 1 diabetes
3. artherosclerosis
4. hypertension
61
What was the recognition of fat stimuli believed to rely mostly on?
1. textural
2. olfactory
3. postingestive cues
62
The initial transduction of lipids in taste cells appears to involve the inhibition of what 3 channels?
1. K+
2. CD36
3. GPCRs (g-protein-coupled receptors)
63
Lipids are a group of naturally occurring molecules that include what 5 things?
1. fats
2. waxes
3. sterols
4. fat-soluble vitamins (A,D,E, and K)
5. phospholipids
64
What are the 3 main biological functions of lipids?
1. storing energy
2. signalling
3. structural components of cell membranes
65
What is the somatosensory detection of fat?
texture (i.e., creaminess)
66
What is the olfactory detection of faft?
odor of impurities
67
How is associated learning related to detection of fat?
postingestive rewarding effects are associated with orosensory cues
68
What are the 8 known fat transduction mechanisms?
1. DRK
2. CD36
3. GPR40
4. GPR41
5. GPR43
6. GPR120
7.FATP
8. GPR113
69
What three fat transduction mechanisms may have a role in taste?
1. CD36
2. GPR40
3. GPR120
70
True or false: triglycerides are insoluble
True
71
This in saliva can cleave free fatty acids that are soluble at concentrations that can stimulate taste bud cells
lingual lipase
72
Describe the possible fatty acid induced signal transduction mechanisms in taste cells
73
This type of taste is the taste of acids
sour taste
74
This kind of taste has at least one proton that dissociates in aqueous systems
sour taste
75
Is the acid strength in a solution a major determinant of sour sensation?
no
76
What 3 things are the determinant of sour sensation?
1. molecular weight
2. polarity
3. size
77
a substance that releases H+ ions in an aqueous solution
acid
78
What are 3 properties of acids?
1. sour taste
2. proton donors
3. contain hydrogen
79
these are proton acceptors
bases
80
Does H+ ion concentration correlate with sourness?
no
weak acids have more sour taste than small acids
81
True or false: At the same pH citric acid tastes more sour than HCl
True
82
What is the human detection thresholds for weak acids?
acetic acid = 0.1 mM (pH ~3.9)
83
What is the human detection threshold for strong acids?
HCl = ~8 mM (pH ~2)
84
What are the two channels that are activated by low pH?
ASICs (Acid sensitive ion channels)
- not expressed in Type III cells
HVCN1 (hydrogen voltage gated channel 1) proton-gated ion channel
- not expressed in Type III cells
85
What channel is inactivated by low pH?
potassium channel
86
Most channels that are sensitive to pH fall into which category
A) Channels activated by low pH (such as ASICs and HVCN1)
B) Channels inactivated by low pH
B) channels inactivated by low pH
87
ASIC
acid sensitive ion channels
88
HVCN1
hydrogen voltage gated channel 1
89
Sour sensing is mediated by what 3 receptor proteins?
1. PKD2L1
2. PKD2L3
3. HCN1
90
Describe the two mechanisms in sour taste transduction
membrane depolarization by inhibiting K+ channel
91
What happens if you knockout the OTOP1 receptor?
eliminates acid responses from sour sensing taste receptor cells (TCRs)
92
What are the 8 health benefits of sour taste?
1. digestion
2. circulation
3. energy
4. heart strength
5. relieves thirst
6. maintains acidity
7. sharpens senses
8. minerals from food
93
What are the 10 adverse effects of acidic foods?
1. listlessness
2. depression
3. headaches
4. acne
5. dry skin
6. mood swings
7. poor digestion
8. brittle nails and hair
9. sensitive gums
10. bacteria and virus resevoir
