Exam 2 Notes Flashcards
(97 cards)
1
Q
carbohydrates
A
carbo="carbon" hydrate="water" carbohydrate="carbon water" C+H20=CHO plant derived food
2
Q
glucose
A
- the most simple carbohydrate in our body
- simple sugar
- found in green plants
- C6H12O6
- through the process of photosynthesis
- light energy becomes chemical energy present in chemical bonds
- the plant uses glucose as an energy source to grow just like we do as humans
- broken down into CO2 and H2O for use by the plant to grow
- whatever is left over is available for animals (including humans) that consume the plant
- called blood sugar
- fuels the body and the brain
3
Q
monosaccharides
A
- mono=”one”
- saccharide=”sweet thing”
- monosaccharide=”one sweet thing”
- single sugars
- glucose, fructose, galactose
- -all are C6H12O6; however, the difference is the chemical structure: the placement of the double bonds and OH groups are different depending on the simple sugar
4
Q
disaccharides
A
- di=”two”
- saccharide=”sweet thing”
- disaccharide=”two sweet things”
- double sugars
- lactose, maltose, sucrose
5
Q
lactose
A
one unit of glucose and galactose
6
Q
maltose
A
two units of glucose
7
Q
sucrose
A
one unit of glucose and fructose
table sugar
8
Q
monosaccharide sugar digestion
A
monosaccharides (glucose, fructose, galactose) are absorbed into the bloodstream and get shuttled to the liver
- glucose can go anywhere (including liver). fuels blood and tissues. also can go to the brain
- fructose goes to the liver and gets packaged into lipids (as fat in our liver)
- galactose goes to the liver and is converted to glucose. it can then go back into the blood and do things for out body
9
Q
disaccharides (lactose, maltose, sucrose)
A
carbohydrates starts to get broken down in the mouth by alpha-amylase and further digestion in the stomach and small intestine and it becomes disaccharides. the disaccharides are then broken down into monosaccharides which can then go to the bloodstream and follow the monosaccharide digestion
10
Q
polysaccharides
A
- “many sweet things”
- many glucose units linked together
- complex carbohydrates
- starch
- glycogen
11
Q
starch
A
plant polysaccharide of glucose
often resists digestion
–cooking makes it more digestible
12
Q
glycogen
A
- storage form of glucose
- animal polysaccharide of glucose
- highly branched
- stored in the liver and muscle tissues
- not a complex carbohydrate, because not available from food
- first carbon in glucose on the starch chain is bonded to the fourth carbon in glucose of the starch chain (1-4 bond)
- -alpha amylase breaks this 1-4 bond
13
Q
fiber
A
- non-digestible by human enzymes
- some fermented by bacteria in the colon
- release CO2 and H2O
- two types: soluble fiber and insoluble fiber
- consumption of fiber in the US is grossly under consumed
14
Q
soluble fiber
A
dissolve in water
form gels (pectin-from suit)
decrease heart disease (binding bile, lowering cholesterol)
blood glucose control (slow transit=slow absorption)
15
Q
insoluble fiber
A
do not dissolve in water do not form gels (corn kernels) digestion and elimination (reabsorption of water) prevent hemorrhoids (soft stool, less swelling veins) prevent appendicitis (prevents compaction, obstruction, and infection)
16
Q
whole grains
A
contains bran, germ, and endosperm of the wheat plant
17
Q
what is lost in white flour
A
iron, B-vitamins (thiamin, riboflavin, niacin), magnesium, zinc, phytochemical form bran and germ, and fiber
18
Q
bile in digestion
A
an emulsifying agent
-allows for lipid and water mixture in fat digestion
-think dish soap
-contains cholesterol
critical for fat digestion and absorption
made and secreted by the liver
-normally the cholesterol in bile is reabsorbed from the intestine for reuse
19
Q
soluble fiber and bile cholesterol
A
fiber carries some of the cholesterol from bile out in the feces
without free cholesterol, liver has to pull cholesterol from the body to synthesize more bile
-takes cholesterol out of the blood
20
Q
soluble fiber in cholesterol-lowering role
A
two fold:
- elimination in the feces
- liver pulls cholesterol stores for bile production
21
Q
cholesterol
A
heart disease is an inflammatory disease
soluble fiber has been associated with lower amounts of inflammatory substances in the body
22
Q
soluble fiber and heart disease
A
three fold:
- eliminates cholesterol in the feces
- liver pulls cholesterol stores for bile production
- inflammatory response to atherosclerotic plaque is decreased
23
Q
recommended fiber intake
A
AI for fiber -~25g/d for females ~38g/d for males there is no UL for fiber includes both soluble and insoluble
24
Q
from carbohydrates to glucose
A
- alpha-amylase in mouth starts digesting starch. maltose is released
- continues into top of stomach until stomach acid deactivates the enzyme
- pancreas releases enzymes to break small polysaccharides into disaccharides and monosaccharides
- resistant starch: not digested until the colon (bacterial fermentation), technically fiber
25
glucose sugar digestion
enters the bloodstream and gets carried to blood and tissues
26
fructose
enters the bloodstream and is brought to the liver and lipids
27
galactose
converted into glucose
28
disaccharide sugar digestion
broken down into monosaccharides and then follow the individual monosaccharide digestion
29
glycolysis
energy to fuel the body
| energy to fuel the brain
30
ketosis
a metabolic state characterized by raised levels of ketone bodies in the body tissues
-may be the consequence of a low carb diet
31
glucose regulation
pancreas releases insulin
- muscles takes glucose to make glycogen (insulin must be present)
- stimulates lover to make glycogen
- adipose takes glucose (insulin must be present)
32
glycogen
2/3 of body is glycogen
~1/3 generous with release to blow for other tissues
minute storage for starvation
glucagon stimulates lover enzymes to break down glycogen
33
too much glucose
2,000 kcal glycogen turns to 70,000 kcal of fat
34
glycemic index
ranking system for foods according to their potential to raise blood glucose relative to a standard, such as glucose
35
blood glucose regulation
1) after a meal, glucose rises, signaling the pancreas to release insulin into the bloodstream
2) insulin signals fat (adipose) tissue and skeletal muscles to take up glucose from the blood. it also stimulates glycogen storage by the liver
3) blood glucose falls to its normal concentration
4) in response to normal blood glucose, the pancreas slows its insulin output
5) as body cells use up glucose, blood glucose declines, signaling the pancreas to release glucagon into the bloodstream
6) glucagon signals the liver to break apart its stored glycogen, releasing glucose into the bloodstream
7) blood glucose rises to its normal concentration
8) in response to normal blood glucose, the pancreas slows its glucagon output
36
the usefulness of fats in the body
energy fuel, energy stores, emergency reserve, padding, insulation, cel membranes, and raw materials
37
the usefulness of fats in food
nutrients, transport, energy, sensory appeal, appetite, texture, and satiety
38
satiety
feeling of fullness (satisfaction) following a meal
- slows movement of food through digestive tract
- communicates with brain
39
fat storage
- fat cells contain blood capillaries and lymph
- subcutaneous fat=under the skin
- adipose tissue=fat
- when you gain weight you do not have more fat cells being created; instead, the fat cells have just increased in size
40
types of lipids
triglycerides, phospholipids, and sterols
41
triglycerides
-major form of fat in food and in the body
-95% of fats are triglycerides
-glycerol+3 molecules of fatty acids
-tissues can easily assemble and disassemble triglycerides
-chain length CX:S
EX: C18:0 means carbon 18 and 0 degree of saturation (degree of saturation=# of double bonds)
42
phospholipids
- glycerol+2 fatty acids
- phosphate in place of third fatty acid (soluble in water)
- -emulsifier
- -mayonnaise .vs. salad dressing
- -lecithin is an emulsifier
- phospholipid bilayer
43
sterols
- rings of carbon with side chains of carbon, hydrogen, and oxygen
- cholesterol: raw material in making emulsifiers in bile
- vitamin D: made from cholesterol
- plant sterols
44
fat digestion and absorption
oil and water do not mix; however, when emulsifiers are added the oil forms smaller droplets (Micelles) and mixes in the water
45
bile
- key to fat digestion
- made by the lover
- stored in the gallbladder
- emulsifies fat into smaller pieces so digestive enzyme can split fatty acids from their glycerol backbone
46
fat transport
- glycerol and shorter chain fatty acids can pass through intestinal lining and into the bloodstream to travel unassisted to the liver
- larger fats cannot travel through the bloodstream, because of oil separation from water. they need chylomicrons
47
chylomicron
- lipoprotein="fat protein combination"
- lipids from a meal clustered together (as triglycerides) with carrier proteins in the cells of the intestinal lining
- transport fats from foods to the liver and other tissues
48
very-low density lipoprotein (VLDL)
transport triglycerides form liver to tissues
49
low-density lipoprotein (LDL)
made from VLDL when triglycerides have been donated to cells
| transport cholesterol and other lipids to cells
50
high-density lipoprotein (HDL)
clears cholesterol from cells and carries away to the liver for disposal
51
storing and using body fat
storage in times of excess
use in times of deprivation
glucose can be broken down into fragments that provide immediate energy for the tissues or if the tissues need no more energy the fragments can be reassembled not back into glucose but into fatty acid chains
52
essential fatty acids
linoleic acid and alpha-linolenic acid
53
linoleic acid
C18:2
omega-6 fatty acid
double bonds on the 9th and 12th carbons
percursor to arachidonic acid
starting material of eicosanoids (bio regulators, similar to hormones)
constrictor
EX: constricts to blood vessels to help control blood pressure
54
alpha-linolenic acid
C18:3
omega 3 fatty acid
fouble bonds on the 9th, 12th, and 15th carbons
precursor to eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)
limited in the body
abundant in fish
dilator
EPA form eicosanoids that oppose arachidonic acid (expands blood vessels)
55
food sources of omega 6
vegetable oils, margarines, nuts an dseeds, poultry fat
56
food sources of omega 3
vegatable oils, nuts and seeds, vegetables, human milk, fish and seafood
57
EPA and DHA in human health
```
heart health (regulate heart, blood vessels, and clotting)
cancer (emerging, inflammation as a possible machanism)
cell membrane function (physical structure)
brain function and vision (DHA accumulation, communication, reduce inflammation associated with aging, retina, and brest milk/fortified formula)
```
58
C:18:0
saturated fatty acid
59
C:18:1
MUFA (mono-unsaturated fatty acid)
60
C:18:2
PUFA (poly-unsaturated fatty acid)
61
trans fatty acid
hydrogen across from each other/on different sides of carbon
62
cis fatty acid
hydrogens adjacent to each other/on the same sides of carbon
63
healthy fat
a person wants to be eating more nsaturated fats in food
| stay away from trans fat
64
lipase
an enzyme that breaks down fat to use it as energy-primary source
65
protein
from the greek word proteios meaning "of prime importance"
made up of amino acids
proteins contain nitrogen in addition to carbon, hydrogen, and oxygen
66
amino meaning
nitrogen containing
67
amino acid structure
backbone=amine group, hydrogen, and acid (carboxyl) group
| side chain differentiates one amino acid from another amino acid
68
amino acid chains
single amino acids create strands
the strands coil and ceate ribbons due to attractions
the coils then start to fold on themselves
they are all clumped together
-heat denautres these proteins and causes them to fall apart/straighten
69
___total amino acids
20
| some are considered essential and some are not
70
essential amino acids
```
histidine
isoleucine
leucine
lysine
methionine
phenylalanine
threonine
tryptophan
valine
-essential because your body can't make them and it needs to be obtained from food
```
71
non essential amino acids
```
alanine
arginine
asparagine
aspartic acid
cysteine
glutamic acid
glutamine
glycine
proline
serine
tyrosine
```
72
how many proteins are there
a single human cell may contain up to 10,000 proteins, each present in thousands of copies from the 20 amino acids that there are
73
amino acid sequences
every protein has an amino acid sequence
the sequence is dictated by genes
"coding"
74
denaturation
distorted sequence
-unfolding proteins
important for digestion
-stomach acid opens up the protein structure
-opens protein to expose peptide bonds
-digestive enzymes cleave peptide bonds
--pepsin breaks down peptide bonds because it is a peptidase
75
protein digestion
mechanical digestion in the mouth
chemical digestion in the stomach (HCl denatures proteins, pepsin begins cleaving peptide bonds @pH of 2)
chemical digestion in the small intsetine (mostly polypeptides, some single AA, pH 7, more digestive enzymes break polypeptides down to tripeptides, dipeptides, and single AA, what is started to break down in the stomach is finished being broken down here)
76
importance of protein
```
protein turnover (red blood cells live for 90-120 days, cells lining the intestinal tract live for 3 days, skin cells are shed and replaced daily)
the process of breakdown, recovery, and synthesis is protein turnover
```
77
roles of protein in the body
- structure (build bones, blood vessels, ligaments, cells, etc..)
- movement
- enzymes, hormones, and other compounds are made of proteins
- antibodies are made of protein (people with protein deficiency have a weak immune system)
- transport (active, passive, and facilitated)
- fluid and electrolyte balance
- acid-base balance
- proving energy and glucose
78
active transport
need a protein to help a molecule move through the phospholipid bilayer-REQUIRES APT (APT=storage form of energy)
79
passive transport
a molecule easily moves through the phospholipid bilayer-DOES NOT REQUIRE APT
80
facilitated transport
a proein will except a molecule and will transfer it through the phospholipid bilayer but DOES NOT REQUIRE APT
81
how do proteins in the body provide energy and glucose
- AA supply energy and many can be conoverted to glucose (fatty acids do not become glucose)
- -nitrogen stripped off and used elsewhere or incorporated by the liver into urea
- -C,H,O that remain can be used to build glucose or fatt acids. Sarcopenia (in elderly-the breakdown of muscle-is a natural phenomenon)
- no storage form of protein
- -taken from body tissues
- -excess used to meet energy needs, make glucose to store as glycogen, or make fat for storage
82
dietary protein needs
balance in body of the amount we need
- protein breakdown (protein loss, eat a meal, protein synthesis, protein accretion)
- there is a number in our body that is a steady state but the cycle is always occurring
- -above balance=protein accretion
- -below balance=protein loss
83
DRI for protein
0.8g/kg of body weight
| protein needs depend on size and stage of growth
84
positive nitrogen balance
more nitrogen in than out
building more protein than is being broken down
growing child has more blood, bone, and muscle at the end of each day (and therefore more nitrogen)
85
negative nitrogen balance
more nitrogen out than in
-reaking down more protein than is being built
an astronaut is breaking down muscle and has less at the end of eac day (therefore less nitrogen)
86
protein quality
```
amino acid composition (if you don't have all the amino acids you will not get a high quality protein)
protein digestibility (how well you get protein from the food you eat)
```
87
diet lacking essential amino acids
cells: breakdown internal proteins to liberate needed amino acids
limit synthesis of proteins to conserve essential amino acids
88
limiting amino acids
refers to the rate-limiting amino acid
an essential amino acid that is present in dietary protein in an insuffucuent amount, therby limiting the body's ability to build protein
89
complementary proteins
two or more proteins whose amino acids complement each other to provide essential amino acids
-what is missing in one is supplied by the other
--1: high in A, low in B
--2: low in A, high in B
EXS: beans and rice, PB and whole wheat toast, pita bread and hummus
90
what foods have a score of 1.00 on the PDCAAS scale
soy, eggs, milk
91
what does PDCAAS mean
Protein Digestibility Corrected Amino Acid Score
92
kwashiorkor
"the sickness the baby gets when the new baby comes"
causes edema in the stomach making it appear swollen
not necessarily calorie deficient-just protein deficient
severe protein energy malnutrition: edema, irritability, ulcerating dermatoses, enlarged liver with fatty infiltration, and a reduced appetite
(when giving these children protein again it needs to slowly be introduced so their liver is not damaged
93
marasmus
```
calorie deficiency
severe protein and caloric deficiency
-loss of muscle and fat
-more common in infants (<1 year)
-starving and hungry with appetite
```
94
gluten
a protein present in grains, particularly wheat grain, that gives stretchy texture to yeast breads and provides bulk and texture to other foods made from wheat and other gluten-containing grains (EX: barley and rye)
95
celiac disease
an autoimmune disease where the villi in the intestines are damaged and shortened-meaning less surface area-which means nutrients cannot be absorbed well
-when gluten is consumed the body attacks itself
96
non-celiac gluten sensitivity
clearly the body does not tolerate gluten; however, the tests for celiac cannnot detect it in their system
97
gluten free for everybody?
not necessarily healthy or a good thing for everyone
manufactured gluten-free foods are often higher in added sugars, fats, calories, and cost than non-gluten free counterparts
