chap 41 Flashcards
(148 cards)
1
Q
which cells are responsible for secreting the components of gastric acid
A
- chief cells
- parietal cells
2
Q
which of the following are components of gastric acid
- amylase and pepsin
- HCl and bile
- HCl and amylase
- HCl and pepsin
A
HCl and pepsin
3
Q
the breakdown of starch by amaylse is the example of
A
chemical digestion
4
Q
which large biological molecules undergo chemical digestion in the oral cavity
A
carbohydrates
5
Q
which large biological molecules undergo chemical digestion in the stomach
A
proteins
6
Q
which of the following are part of the alimentary canal?
- small intestine
- liver
- gallbladder
- pancreas
A
small intestine
7
Q
which large biological molecules undergo chemical digestion in the small intestine
A
fats
proteins
carbohydrates
nucleic acids
8
Q
Which classes of large biological molecules is digested by enzymes from the pancreas?
A
fats
proteins
carbohydrates
nucleic acids
9
Q
herbivores eat what?
A
plants and algae
10
Q
carnivores eat what?
A
other animals
11
Q
omnivores eat what
A
plants, algae, and other animals
12
Q
what animal food group category are humans in
A
omnivore (plants, algae, and animals)
13
Q
most animals are oppertunistic eaters, what does this mean
A
they eat what they can when the can;
they eat food outside their diet when their usual foods aren’t available
14
Q
cells, tissues, organs, and animals depend on what to drive their cellular bodily process
A
ATP, energy needed for life
15
Q
what substrates are needed to generate ATP during cellular respiration
A
carbohydrates, proteins, lipids
16
Q
why must you digest/ingest food?
A
- provide ATP
- generate raw materials needed for biosynthesis of large biological molecules
- obtain essential nutrients
17
Q
what is a major dietary source of organic carbon?
A
carbohydrates
18
Q
what is a major dietary source of organic nitrogen?
A
proteins
19
Q
what are the 4 essential nutrients
A
amino acids
fatty acids
vitamins
minerals
20
Q
what is an essential nutrient
A
nutrients that animals need, but can’t synthesize
21
Q
why do animal cells need essential nutrients
A
the molecules are required for many biosynthetic reactions within cells
22
Q
how are most enzymes derived
A
from diet, body can’t make them
23
Q
how many amino acids do humans need in their diet
A
8
24
Q
what type of food contain all 8 amino acids
A
animal products (meats, eggs, cheeses)
25
what amino acids do human infants require in addition to the 8
histidine
26
how do essential nutrients generally function
substance that enzymes work on
coenzymes
cofactors
27
why are fatty acids essential to animal cells
the cell can't synthesize them and they are needed to build things
28
how many essential vitamins are there
13 vitamins (that can't be synthesized by animal cells)
29
whats the function of water soluble vitamins
production of nucleic acids and red blood cells
30
what are the symptoms of deficiency of water soluble vitamins
anemia, numbness, loss of balance
31
whats the function of fat soluble vitamins
helps body absorb and use calcium and phosphorus
32
what are the symptoms of deficiency of fat soluble vitamins
rickets in children
| bone softening in adults
33
how are water soluble vitamins dietary claimed
meats, eggs, dairy products
34
how are fat soluble vitamins dietary claimed
egg yolk, sunlight, dairy products
35
How does rickets impact the the shape of a femur
it is bowed
36
how is calcium derived in diet
diary products, green vegetables
37
how is sodium derived in diet
table salt
38
how is chloride derived in diet
table salt
39
how is iodine derived in diet
seafood, dairy products, iodized salt
40
what is the difference between vitamins and minerals
vitamins are organic molecules.
| minerals are inorganic molecules
41
what is goiter
a disease due to frequently not getting enough iodine
42
why is iodine deficiency less common in the united states
a lot of salt is consumed in our diets
43
the american diet takes is how much more salt than what is actually needed
20x more
44
excessive salt consumption contributes to what
high blood pressure
45
what causes malnutrition
under-nutrition
| deficiencies in essential nutrients
46
what is malnutrition
failure to obtain adequate nutrition
47
under-nutrition is commonly found in?
eating disorders
48
what are potential effects of undernutrition
```
uses up stored fats
body breaks down own proteins
muscle decreases and brain becomes deficient
death
damage can be irreversible
```
49
whats an example of essential nutrient deficiencies
populations on rice diet frequently deficient in vitamin A (causing blindness/death)
50
what is essential nutrient deficiency
long term absence of 1+ essential nutrients
51
what are potential effects of essential nutrient deficiency
deformities
disease
death
52
what are the 4 stages of food processing
ingestion
digestion
absorption
elimination
53
what is ingestion
act of eating or feeding
54
what is digestion
food is broken down into molecules that are small enough for the body to absorb
55
mechanical digestion
breaks food into smaller pieces which increases the surface area
56
chemical digestion
molecules breaking down into their monomers through hydrolysis
57
what is absorption
uptake of small nutrient molecules into blood or lymph vessels
58
what is elimination
passage of undigested material out of the digestive system
59
alimentary canal is also known as
gastrointestinal tract
60
accessory organs
An organ that helps with digestion but is not part of the digestive tract
61
peristalsis
alternative waves of contractions and relaxation of smooth muscle
62
sphincters
muscles that form ring like valves that close off compartments within the alimentary canal
63
what is the function of peristalsis
to move food through the alimentary canal
64
what is the function of sphincters
regulate the passage of material through different parts of the different parts of the alimentary canal
65
what is the digestive system in the oral cavity
```
chewing food
nervous reflex
saliva from salivary glands
amylase -- hydrolase
starch, glycogen --> small polysaccharides and disaccharides
```
66
saliva contains
mucus, buffers, antibacterial agents
67
what is mucus
mixture of water, salts, cells, mucins (slippery glycoproteins)
68
what are buffers
neutralize acids and protects teeth
69
what are antibacterial agents
lysosomes that destroy microorganisms that enter the mouth with food
70
what is the tongue's function
evaluates ingested material and process it for swallowing
71
what is the bolus
ball of chewed food shaped by the tongue
72
what occurs when not swallowing a bolus
- esophageal sphincter muscle is contracted
- epiglottis is up and glottis is open
- air can easily enter the lungs via trachea
73
what occurs when the bolus reaches the throat region
- swallowing reflex is triggered
- epiglottis tips over glottis which prevents food from entering the trachea
- esophageal sphincter relaxes allowing bolus to enter the esophagus
74
what occurs after the bolus enters the esophagus
- esophageal sphincter muscle contracts
| - peristalsis moves bolus down the esophagus and towards the stomach
75
breaking down amylase is an example of
chemical digestion
76
which large biological molecule undergoes chemical digestion in the oral cavity
carbohydrates
77
the stomach is lines with
gastric glands w/ several diff types of cells
78
function of mucus cells
secrete mucus that lubricates and protects cells of the stomach from harsh chemicals
79
what is the function of chief cells
secrete pepsinogen, an inactive form of the protease, pepsin
80
what is the function of pepsin
an enzyme that digests peptide bonds and break proteins into small polypeptides
81
what pH does pepsin have to be at to work
pH 2
82
what is the function of the parietal cells
secrete HCl to:
activate pepsinogen to pepsin
kill bacteria
denature proteins
83
what is the function of g-cells
produce the hormone gastrin which stimulates production of gastric juices
84
are the epithelial cells that line the stomach vulnerable to acid pH and pepsin digestion
yes, but the cells secrete enough mucus that protects against self-digestion
85
how often to epithelial cells replicate
replaced every 3 days
86
what is a gastric ulcer
damaged parts of the stomach lining
87
what is the cause of stomach ulcers
bacterial infections by H pylori
88
what are the cells that line the stomach
epithelial cells
89
how are stomach ulcers treated
with antibiotics
90
what is the only enzyme that can break down in the stomach
pepsin
91
where does most chemical digestion take place
SI
92
how long is the SI in length
6 meters
93
what is the duodenum
first 25 cm where chyme from stomach mixes with digestive juices from pancreas, liver, and gallbladder
94
what does the SI get its name from
its diameter not its length
95
the pancreas has enzymes that help digest what
proteins, carbohydrates, lipids, and nucleic acids
96
pancreatic enzymes work best at what pH
pH 7-8
97
Where is bile released to for digestion
gallbladder
98
what produces bile
liver
99
where is bile stored
gallbladder
100
what is bile
fluid that aids in digestion
101
what are bile salts
salts that act as detergents and increase surface area for digestion
102
what part of the digestive system contains bicarbonate to neutralize the acidity of chyme
pancreas
103
what aids in the destruction of red blood cells that are no longer functional and breaks down toxins
bile
104
The absorption of molecules takes pace where in the SI
lleum
105
what is the purpose of all the folds in the small intestine
to increase surface area
106
purpose of microvilli
increase the surface area of each epithelial cell to increase the total capacity for nutrient absorption
107
describe absorption in the small intestine
movement of molecules from lumen through epithelial cells into the blood capillaries or lacteal
108
purpose of fructose
facilitates diffusion to cross epithelial cells
109
AAs, glucose, small peptides require energy for what
use active transport mechanisms to cross epithelial cells
110
what keeps fat droplets from coalescing in the lumen during absorption
bile salts
111
what digests triglycerides into fatty acids and monosaccharides during absorption
pancreatic lipase
112
after fatty acids and monoglycerides diffuse into epithelial cells, what happens during absorption
recombine into triglycerides
113
what are assembled within the epithelial cells that line in the SI during absorption
chylomicrons
114
what are chylomicrons
large water-soluble globules that can't enter the blood vessels found in the villus
115
how do chylomicrons leave epithelial cells
exocytosis and enter lacteals
116
after chylomicrons circulate through lymph vessels, where do they go next
pass through the left subclavian vein
117
what do chylomicrons consist of
proteins
cholestrerol
phospholipids
triglycerides
118
why cant fats enter the capilary system
they are too large
119
what vessels do fats enter
lacteal vessels
120
how do monosaccharides, AA, nitrogen bases, ribose, deoxyribose, phosphates enter the heart
villi capillaries --> hepatic portal vein --> liver --> heart
121
what happens when glucose is in access and and energy is low
glucose is converted to glycogen within liver
122
how do fats enter the heart
chlyomicrons --> lacteals --> larger lymph vessels in lymphatic system --> large vein --> heart
123
what regulates the distribution of nutrients to the rest of the body
liver
124
if there's not enough food, how does the body adapt
the body breaks off part of the glucose that is already stored
125
which of the large biological molecules are digested in the large intestine
none
126
whats the function of the large intestine
completes the reabsorption of the water that began in the small intestine
127
what is feces
waste of the digestive system
128
feces contain cellulose to help function in what
to move food along the alimentary canal
129
the bacteria in feces do what?
- live off the unabsorbed organic material within the gut
- generates gases
- synthesizes vitamins
130
rectum function
terminal portion of the intestine that stores feces
131
whats the inner sphincter of the rectum
involuntary muscle
132
whats the outer sphincter of the rectum
voluntary muscle
133
microbiome function
the collection of bacteria that inhibit our guts
134
what is a hormone
a chemical signal that is synthesized by an endocrine to trigger a response in the target cell
135
how are non-target cells involved in the hormonal regulation of digestion
they aren't, they aren't able to receive a chemical signal
136
what are the hormones that play a role in the coordination of the digestive process
gastrin
secretin
cholecytskinin
137
what are the hormones that play important roles in regulating blood glucose levels
insulin
| glucagon
138
what is the function of gastrin
coordinates digestion within the stomach
139
what does the stimulus do when food arrives in the stomach
- triggers release of gastrin from g-cells to blood stream
- returns to stomach and acts on target cells to stimulate the gastric juices
- stimulus is removed after food is removed
140
what is the function of the CCK in the small intestine
release of digestive enzymes from pancreas and bile from gallbaldder
141
what is the function of the secretin in the small intestine
increases release of HCO3- that neutralizes chyme (on pancreas)
142
both secretin and CCK work together to operate what function
act on the stomach to inhibit peristalsis and secretin of gastric juices
143
what slows down digestion of the chyme within the stomach before it enters the SI
cck and secretin
144
Type 2 diabetes is characterized by a failure of target cells to respond normally to insulin. What best describes the resulting glucose levels in a type 2 diabetic and strategy for treatment
high blood glucose levels, that increase sensitivity to insulin
145
insulin targets what what cells?
targets muscle and liver cells
146
what stimulates glucose uptake and stimulates glucagon synthesis
insulin
147
what targets liver cells
glucagon
148
what stimulates glycogenolysis and breaks down glycogen
glucagon
