physci midterm Flashcards
1
Q
what were the common causes of death in 1900 vs today?
A
1900 - acute disease
today - chronic disease
2
Q
what is an acute disease?
A
starts and ends; can be treated and gotten rid of e.g. a cold
3
Q
what is a chronic disease?
A
develops over time and symptoms must be managed over the rest of the life e.g. diabetes
4
Q
how to determine obesity?
A
fat percentage, waist circumference, BMI
5
Q
how to determine fat percentage?
A
submerge in water, caliper method (measure fat folds), imaging techniques - vexa, modern scales can measur eby sending electrical signals
6
Q
what fat percentage is obese for males and females?
A
m: > 25%
f: > 30%
7
Q
what waist circumference is obese for males and females?
A
m: > 40 in
f: > 35 in
8
Q
how to calculate bmi?
A
weight (kg) / [height (m)]2
9
Q
what bmi is considered obese for males and females?
A
m: > 30
f: > 25-29
10
Q
food vs nutrition
A
food is what you consume while nutrition is the science of food (beneficial or not based on what the food is doing inside your body)
11
Q
food vs nutrition
A
food is what you consume while nutrition is the science of food (beneficial or not based on what the food is doing inside your body)
12
Q
what does it mean to have physical health?
A
free of disease; wellness
13
Q
how does emotional health affect physical health?
A
stress eating; not eating because of stress or sadness; not exercising because feeling down
14
Q
how does social health impact physical health?
A
individuals with high levels of fitness tend to have friends who are of a similar level of fitness; individuals who are obese tend to have friends who are obese
15
Q
can food affect health?
A
to an extent – diseases caused by an excess/deficiency in a nutrient can be affected by the consumption of the nutrient, but some diseases will occur regardless (e.g. osteoporosis can be caused by calcium deficiency, but can still get osteoporosis even if consume lots of calcium)
16
Q
examples of diseases affected by nutrition [4]
A
type 2 diabetes
heart disease
hypertension
certain forms of cancer
17
Q
examples of diseases affected by nutritional deficiency or toxicity [3]
A
pellagra - niacin (b3) deficiency
scurvy - vitamin C deficiency
anemia - iron deficiency
18
Q
what are the 3 essential caloric nutrients?
A
carbohydrates, proteins, lipids
19
Q
what is the function of carbohydrates?
A
convenient form of fuel, muscles like it because it’s quick
red blood cells can only use it
20
Q
where do carbs come from?
A
mostly plant based (wheat, rice, potatoes); some comes from animals; main form is starch
21
Q
what does the body do with starch?
A
converts it to glycogen
22
Q
where does the body store carbohydrates?
A
muscles
23
Q
What is the leading cause of death in the united states and worldwide?
A
Cardiovascular diseases
23
Q
What is the leading cause of death in the united states and worldwide?
A
Cardiovascular diseases
24
Risk factors for developing cardiovascular disease [7]
```
Tobacco
Lipids
Hypertension
Physical inactivity
Diabetes
Obesity
Diet
```
25
What is the most preventable risk factor of cardiovascular diseases
Tobacco
26
How is tobacco a risk factor for cardiovascular disease?
Not well known but possibly bc the carcinogens increase the buildup of plaques in blood vessels and development of atherosclerosis and hypertension
27
How do lipids affect cardiovascular diseases?
High cholesterol levels are associated with build up of plaque
28
What is hypertension?
Systolic blood pressure above 140 mmHg (norm is 120)
29
What is a major source of carbohydrates?
Plants
30
What chemicals are carbs made of?
CHO
31
In what forms are carbs found?
Sugars, starches, and cellulose
32
Where/how do carbs exist in the body?
As glucose in blood and glycogen in liver and muscles
33
What is the main function of carbs?
Source of energy to drive basic functions of cells in the body
34
How many calories in a gram of carbs?
4
35
How are carbs used?
When cell activity increase, the stored glycogen is broken down into glucose and released in the blood to be a source of energy
36
Why is glucose so important?
Our nervous system cells favor the use of glucose and our red blood cells can only use it as a source of energy
37
What chemical process results in carbohydrates?
Photosynthesis
38
what is a stomata?
Microscopic opening in the leaves of plants that facilitate the intake of carbon dioxide into their photosynthetic cell
39
What is the simplest form of carbs?
Monosaccharides
40
What is a monosaccharide/monomer and what are the three types?
Has one sugar molecule - glucose, fructose, galactose
41
What is a disaccharide?
2 sugar molecules
42
3 disaccharides
Sucrose, fructose, and maltose
43
What is sucrose made of?
One glucose and one fructose
44
Where is sucrose found? (Examples)
Fruits, vegetables, honey, sugar beets, sugar cane, and maple syrup
45
What is lactose made of?
One glucose and one galactose
46
Where is lactose found?
Milk / dairy
47
What is maltose made of?
Two glucose molecules
48
Where does maltose come from and what is it used in?
Produced by the fermentation process and used in alcoholic beverages (rarely found in natural food)
49
What is a polysaccharide?
Long chains of glucose molecules (20+)
50
What are the 3 types of polysaccharides?
Starch, glycogen, and fiber
51
Where is starch found?
Many different plant products - grains (seed bearing plants like wheat, corn, rice, rye, and oats); legumes (pod-bearing plants like peas, beans, soy, and lentils); and tubers (modified underground stem and roots of plants such as potato and yams
52
What are the two starch structures?
Amylose - Straight chains
| Amylopectin - branched chains
53
Digestion of amylose vs amylase and why
Amylose - takes longer bc its a straight chain
| Amylopectin - branches help it interact with digestive enzymes faster so it is digested faster
54
What is the most common form of stored sugar in humans/animals?
Glycogen
55
Where do we store glycogen and in what form?
Muscles and liver in a highly branched form
56
What is fiber?
A polymer of glucose - an indigestible form of carbs
57
3 parts of the grain
The endosperm, the germ, and the bran
58
Which parts of the grain contain high amounts of fiber?
The germ and the bran
59
What are the 3 main types of fiber?
Functional fibers, dietary fibers, and total fibers
60
Why is starch digestible and and fibers are not? (Even though they are both glucose polymers)
The types of bonds - alpha glucose vs beta glucose
(Starch connects with alpha and fiber connects with beta) and digestives can only recognize and breakdown the alpha-glucose but not the beta
61
What shape is starch?
Helical
62
What shape is cellulose
Beta-glucose
63
3 common functional fibers
Psyllium, pectin, and plant gums
64
Used for functional fibers
Have Health benefits & are extracted for use in fortifying foods to texturize it and for commercial use in supplements
65
Where is dietary fiber found?
The bran of oats and wheat, cellulose, and fruits and vegetables
66
What is total fiber?
The sum of functional fiber and dietary fiber
67
How to classify fibers based on how they are processed in the digestive system
Soluble and insoluble
68
What do soluble fibers do?
Slow the absorption of glucose and bind to cholesterol in the digestive tract
69
Who are soluble fibers recommended to?
Diabetics and individuals at risk for cardiovascular diseases
70
What have soluble fibers been shown to do and where are they found?
Lower plasma and cholesterol and found in oats, barley, fruit pulp, dried beans, and psyllium
71
Where does the term soluble fibers come from?
They form a gel-like structure when mixed with water
72
What benefits do insoluble fibers have?
Abrasion of the walls of the large intestine stimulates mucus release, preventing constipation
73
Where are insoluble fibers found?
Wheat bran, legumes, the coating of seeds, and skin of fruits and vegetables
74
What are sugar alcohols?
Products of monosaccharides and disaccharides
75
Who uses sugar alcohols?
Diabetics and people on low - carbs diets
76
Why don't sugar alcohols promote tooth decay?
They cannot be digested by bacteria in the mouth
77
4 most common sugar alcohols
Glycerol, sorbitol, mannitol, and xylitol
78
What is glycerol?
Part of triglycerides - the most common type of fat in our body
79
What are triglycerides made of
1 glycerol and 3 fatty acids
80
What happens when triglycerides are broken down and the fatty acids are used as an energy source?
The generated glycerol is used to resynthesize triglycerides
81
What is gluconeogenesis
When a small amout of glycerol is used to make glucose
82
What is glycerin
What glycerol is called when added to food
83
What is glycerin used for?
To provide sweetness and moisture to food
84
Calories in glycerol?
4 kcal/g
85
Why is glycerol better than glucose
Quantity added to food is less and its rate of absorption is slower so it does not evelate plasma glucose rapidly
86
How many calories in xylitol, sorbitol, and mannitol?
2.4 ; 2.6; 1.6
87
What is xylitol used in?
Sugar gum
88
What part of the grain is used in process sugars?
Only the starchy endosperm
89
What hormones are released to maintain the glucose balance?
Insulin and glucagon
90
What is the function of insulin and glucagon?
Lower blood sugar; raise blood sugar
91
Normal level of blood sugar
79-100 mg/dl
92
Where is insulin released from?
The beta cells of the pancreas in hyperglycemic conditions
93
Where is glucagon released from?
The alpha cells of the pancreas in hypoglycemic conditions
94
How long do glucose levels take to return to resting levels after insulin release in healthy individuals?
2 hrs
95
What is the glycemic index?
The level of blood glucose rise and fall after consumption
96
What foods have a high gi vs a low one?
Food broken down quickly has a high gi and food broken down slowly has a low gi
97
What is glycemic load?
How much each ingested gram of carbohydrates raises our blood glucose levels
98
Calculate glycemic load mathematically
GL = carbs (g) x GI / 100
99
Digestive path of carbs
Mouth - salivary amylase starts the breakdown of sugar molecules
Stomach - salivary amylase is destroyed by stomach acid
Pancreas - pancreatic amylase is released into the small intestine
Small intestine - the pancreatic amylase and the disaccharides break sugar into monosaccharides for absorption
100
What are the major organs that uptake glucose?
The muscles, liver, and adipose tissue
102
What is lipogenisis
When excess glucose is ingested and it enters the adipose tissue where it is converted to a fatty acid and stored as a triglyceride
103
which is the most diverse macromolecule?
proteins
104
where are proteins found?
various foods such as plants and animal
105
what do proteins function in? [7]
metabolism, heredity, regulation, immunity, transport, fluid balance, and kidney functions
106
what parts of the body are proteins critical components of? [ 4]
hormones, blood, bones, and connective tissue
107
what are amino acids?
organic molecules made up of a central carbon that is connected to 4 other groups
108
what are the building blocks of proteins?
amino acids
109
what are the 4 groups in an amino acid?
an amino group, a carboxyl group, a hydrogen group, and an R group
110
how many amino acids exist in our body?
20
111
HOW MANY ESSential amino acids are there?
9
112
what makes an amino acid 'essential'?
our body cannot synthesize it on its own
113
what are the functions of proteins? [8]
chemical reactions, signaling, fluid balance, acid-base balance, protection, transport, growth and development, and movement
114
how do proteins function in chemical reactions?
as enzymes to increase the affinity of the substrates to one another
115
how do proteins function in chemical reactions?
as enzymes to increase the affinity of the substrates to one another
116
how do proteins function in signalling?
as hormones to signal small changes in the body to maintain homeostasis
117
how much of our body is made up of water?
60-70%
118
what substances are water insoluble
cholesterol and lipid hormones
119
what is the cell-plasma membrane made of?
phospholipids
120
red blood cell life span
120 days
121
examples of voluntary muscles
skeletal muscles in our extremities, in our skull and face, and at the base of our lungs
122
examples of involuntary muscles
cardiac and smooth muscles
123
what are skeletal muscles?
THE MUSCLES WE use during any form of physical activity
124
what are the two major proteins found in muscles
myosin and actin
125
what are the two major proteins found in muscles
myosin and actin
126
where are proteins found In foods?
all types of meat, dairy products, soy products, legumes, whole grains, and nuts
127
what amino acid is important to insulin
leucine
128
digestion of proteins
mouth - no protein enzymes, just chewing and moistening
stomach - pepsin is released with HCL to break down the proteins into small peptide fragments
pancreas - proteases are released from the pancreas into the small intestine
small intestine - amino acids are absorbed into circulation
129
reccommendation dietary allowance of protein
.8g per 1 kg of body weight
130
what are the 3 macro nutrients
carbs, fat, protein
131
what are carbohydrates function for energy?
stored as glycogen in liver and muscles (one day’s worth of energy)
132
what is fat's function as energy?
most imporant form of stored energy (9 kcals/g and can be stored w/o water)
133
what is protein's function as energy?
not a normal energy source, but can be broken down for energy in extreme cases
of starvation.
134
what are the 2 types of micronutrients?
vitamins and minerals
135
what are minerals?
inorganic ions, usually act as cofactors. Ex: Iron, Zinc, Calcium
136
what are vitamins?
small carbon containing molecules, usually act as coenymes. Ex: Vitamin A, Vitmin C, B12
137
digestive tract
Mouth -> Pharynx -> Esophagus (prevented from going into the trachea by the closing over of the larynx by the epiglottis) -> stomach -> small intestine (Duodenum, jejunum and illium) -> large intestine (Caecum, ascending, transverse and descending colon) -> rectum -> anus.
138
How is food moved through the digestive system?
Peristalsis, a wave of smooth muscle contraction, moves the food down the gut all the way to the anus. Various sphincter muscles form rings at key points and prevent the food from moving in reverse.
139
what digestion happens in the mouth?
Mechanical digestion; Chewing and saliva start digestion (amylase) and
then the food is swallowed. Saliva moistens food, so taste buds can be activated.
140
digestion in stomach
store food so that digestion can take place slower than ingestion; secretes pepsin to begin the breakdown of proteins and HCL to kill ingested microorganisms. This mixture of partially digested food and gastric juice is called chyme
141
How do we produce these destructive digestive enzymes without digesting your own cells and tissues?
enzymes are produced in an inactive form called a zymogen; Only when they are secreted into the gut do they assume their active, destructive form; Stomach is protected by mucus secreted by gastric glands and the gastric mucosa. Mucus contains protease inhibitors and buffers
142
digestion in small intestine
most digestion and absorption of nutrients occurs; internal surface area equal to a tennis court; receives important digestive secretions from the liver and the pancreas:
- The liver supplies bile which speeds fat breakdown by forming micelles from fat molecules and preventing them from clumping together.
- The pancreas produces digestive enzymes and bicarbonate ions which increase the pH of the small intestine. Unlike the stomach, small intestine digestion occurs optimally at neutral or slightly basic conditions.
143
Pancreatic proteases
Trypsinogen, chimotrypsinogen, carboxypeptidase
144
Pancreatic lipase
break down triglycerides
145
Pancreatic amylase
Breaks down oligosaccharides.
146
Pancreatic hormones
Insulin and glucagon (Blood sugar homeostasis)
147
Duodenal disaccharidase
Maltase, sucrose, lactase; breaks down disaccharides into monosaccharide.
148
Duodenal peptidase
Aminopeptidase, breaks down protein to its smalles constituent amino acids.
149
Why is bile needed for fat digestion?
It serves an emulsifier, increasing the surface area of fats exposed to enzymes during digestion.
150
digestion in large intestine
Peristalsis moves the contents of the small intestine on to the large intestine or colon.; water and ions are reabsorbed and feces is formed and stored for later disposal; Bacteria live in the colon and break down matter that we cannot digest. They release byproducts which can be beneficial (Vitamin K, biotin) or not (methane gas)
151
four layers of tissue layering in the gut (listed from the lumen side out
Muscosa; Submucosa; Muscle layer; Serosa
152
muscosa layer
secrete mucus, digestive enzymes, and HCl
153
Submucosa layer
vascularized, absorbed nutrients are carried throughout the body
154
Muscle layer
circular and longitudinal layers are responsible for the contraction of gut and movement of food
155
Serosa layer
layer covering the gut, protection
156
Digestive Disorder
heartburn/GERD; Peptic ulcer; Celiac disease; Crohn disease; Ulcerative colitis
157
heartburn/GERD;
Gastroesophagial sphincter disorder
158
Digestive Disorder
heartburn/GERD; Peptic ulcer; Celiac disease; Crohn disease; Ulcerative colitis
159
heartburn/GERD;
Gastroesophagial sphincter disorder
160
Peptic ulcer
Helicobacter pilori bacteria infection, stomach lining erosion.
161
Celiac disease
Sm intestine lining erosion
162
Crohn disease
Sm intestine lining disorder
163
Ulcerative colitis
LI disease, ulcerative colitis, Polyp in the large intestine
164
chemical makeup of carbs
Carbohydrates Cn(H2O)n = (CH2O)n contain a chain of carbons, each bonded to H and OH groups.
165
where is carb energy stored
strong C-C and C=O covalent bonds
166
functions of carbs (besides energy)
provide structural support, e.g., cellulose; provide tags to address proteins; metabolic products are carbon skeletons for many other molecules; contribute one of the building blocks for DNA (deoxyribose) and RNA (ribose); form part of structural elements of some cells and supplies carbon atoms for synthesis of
cellular components
167
classifications of carbs
Monosaccharides; dissacharides; oligosaccharides; polysaccharides
168
Oligosaccharides
three to 20 monosaccharides
169
glycogen
storage form of carbohydrates in animals, stored primarily in liver and skeletal muscle.
170
starch
storage form of carbohydrates for plants, less highly branched
171
cellulose
Linear, this makes plant cell walls strong
172
benefits of soluble fiber
(oats/barley) slow glucose absorption, lower plasma cholesterol
173
what is Glycemic Index/ its purpose
GI tells us how quickly sugar from food is converted into glucose
• GI doesn’t account for the quantity of carbohydrate in food
• Foods that are digested quickly have higher GI
• Glucose has the highest GI
174
glycemic load levels (what's good)
GL of 20 High [want high GL]
175
chemical structure of protein
large complex molecules made up of amino acids, linked in sequence by covalent peptide
bonds
176
protein structures
primary, secondary, tertiary, qaternary
177
primary protein structures
linear sequence of amino acids (covalent bonds)
178
secondary protein structures
repeated pattern of coiling or folding into sheets (alpha-helix; beta-
pleated sheet) (H-bonds)
179
tertiary protein structures
```
protein folding - (H-bonds, ionic bonds, van der Waals (interior of protein),
disulfide bonds (S-S) from AA cysteine's -SH "sulfhydryl group") -polar side chains tend to face exterior surface; non-polar face center
```
180
quaternary protein structures
more than 1 polypeptide chain (subunits), eg. hemoglobin; similar bonds as in tertiary structure
181
quaternary protein structures
more than 1 polypeptide chain (subunits), eg. hemoglobin; similar bonds as in tertiary structure
182
where is insulin released from
the pancreas
183
what is diverticulosis
a disease associated with the large intestine
184
what should blood sugar levels be
70-100 mg/dl
185
regulating blood glucose level
all of the above
186
insulin acts mostly on what
muscles and liver (plus possible 3rd option)
187
gluconeogeneis is
conversion of amino acids to glucose
188
which is not true about insulin
insulin signals the liver to take up insulin
189
sucrase is released from where
the small intestine
