Lecture Test One Part One Flashcards
1
Q
Why is temperature regulation so important?
A
An imbalance in temperature could cause reactions to enzymes
2
Q
What area of the brain regulates temperature?
A
hypothalamus
3
Q
What is the normal core body temperature?
A
99.6 degrees
4
Q
Humans are classified as ________ which means they are able to regulate their body temperature.
A
homeotherms
5
Q
How is temperature maintained?
A
a balance between heat gained and heat lost
6
Q
What is hyperthermia?
A
heat gain exceeds heat lost
7
Q
What temperature will hyperthermia set in?
A
technically 100 degrees but enzymes will not be affected until temperatures of more than 103
8
Q
What are some common causes of hyperthermia?
A
exercise
environment
fever
9
Q
What will hyperthermia cause?
A
heat stroke
heat exhaustion
10
Q
what are the symptoms of heat exhaustion?
A
flushed, sweating profusely, nasea, dizzy. Patient will survive.
11
Q
What are the symptoms of heat stroke?
A
flushed, vomiting, comatose, patient has stopped sweating
12
Q
A fever is caused by the release of
A
pyrogens
13
Q
Pyrogens from WBCs increase the release of
A
prostaglandins
14
Q
Prostaglandins affect the
A
hypothalamus to raise the set temperature.
15
Q
In theory, prostaglandins reset
A
the thermostat
16
Q
Aspirin is an
A
antiprostaglandin
17
Q
What does aspirin do?
A
It prevents the thermostat from resetting. It will make you feel better but will keep the invader from leaving
18
Q
What is hypothermia?
A
heat loss exceeds heat gain
19
Q
What are some common causes of hypothermia?
A
environment
anesthesia
20
Q
At what temperature will hypothermia set in?
A
95 degrees or lower.
21
Q
What happens to enzymes during hypothermia?
A
It slows them down but does not denature them as in hyperthermia
22
Q
What are some symptoms of hypothermia?
A
decreased heart rate, decreased respiratory rate decreased metabolism vasoconstriction coma death
23
Q
what is the metabolic rate?
A
total amount of energy produced and used by the body per unit of time.
24
Q
what does the metabolic rate compare?
A
ATP use and production
25
what are the three locations for energy use?
basal metabolic rate
thermic affect of food
muscle acttivity
26
what is basal metabolic rate?
energy that keeps resting body functioning. most energy is used for this
27
what is thermic effect of food?
energy needed for digestion of food. least amount of energy used for this
28
what is muscle activity?
energy used for movement of skeletal muscles
29
What will happen if energy intake is higher that enrgy output?
weight gain
30
How many calories does an average 154lb male need daily?
2700 calories
31
How many calories does an average 120 lb woman need daily?
2000
32
what are the two ways to produce ATP?
anaerobically
| aerobically
33
What is anaerobic respiration?
no oxygen needed
no mitochondria
glycolysis followed by fermentation
34
how many ATPs does anaerobic respiration produce?
2 ATPs
35
What is aerobic respiration?
needs oxygen
needs mitochondria
glycolysis, Krebs, ETC
36
How many ATPs does aerobic respiration make?
38
37
All energy is derived from
the sun
38
ATP input comes from
the food we eat
39
What is digestion?
The breakdown of large food molecules into smaller molecules
40
What are the six different activities that the digestion system carries out?
```
Ingestion
Secretion
Motility
Digestion (mechanical and chemical)
Absorption
Elimination
```
41
What is ingestion?
The intake of food
42
What is secretion?
cells within the digestive system will release substances that aid in digestion
43
What are some different types of secretion?
7 liters of water, enzymes, acids, mucus
44
what is motility?
movement of food from one tract to the next
45
what is peristalsis?
rhythmic, involuntary muscle contractions of the gastrointestinal tract
46
What is mechanical digestion?
movements of the GI tract that aid in the breakdown of the food.
47
What are some examples of mechanical digestion?
chewing, peristalsis, mixing
48
what is chemical digestion?
chemical reactions that breakdown organic molecules into smaller ones using enzymes
49
what is an enzyme?
substance that increases the rate of chemical reactions without changing themselves
50
each enzyme will have its own
substrate
51
enzymes work best when they are at
optimal temperature and optimal pH
52
what is absorption?
passage of digested food from the GI tract into vessels (Blood and lymph)
53
what is the purpose of absorption?
so food molecules can be transmitted to and used by body cells
54
what is elimination?
removal of undigested substances from the GI tract.
55
What are the 2 main groups of the digestive system?
GI tract
| accessory structures
56
what is the GI tract?
the organs that the food actually pass through
57
what are the organs of the GI tract?
```
mouth
pharynx
esophagus
stomach
small intestine
large intestine
```
58
What is the length of the GI tract?
25-28 feet
59
what is the total transit time of the digestive system?
24-36 hours
60
what are accessory structures?
they aid in digestion but the food does not go through them
61
what are some examples of accessory structures?
```
teeth
tongue
salivary glands
liver
gallbladder
pancreas
```
62
What are the histology layers of the digestive tract?
tunica mucosa
tunica submucosa
tunica muscularis
tunica serosa
63
What is the mouth
opening of the digestive tract from lips to pharynx
64
what are the two compartments of the mouth?
vestibule
| oral cavity
65
what is the vestibule?
area of the mouth between the cheeks and the gums (gingiva)
66
what is the oral cavity?
lined by hard and soft palate superior, uvula posterior, teeth anterior
67
what are the two sets of teeth that humans have
primary/deciduous
| secondary/permanent
68
why are teeth important?
mechanical digestion and speech
69
what are the four different types of teeth?
incisors
canines
premolars
molars
70
The deciduous teeth enter the gingiva beginning at
6 months
71
When are deciduous teeth usually complete?
age 2
72
when do permanent teeth begin forming?
age 5 or 6
73
The tongue is mostly composed of
skeletal muscle
74
The tongue is attached to the bottom of the mouth by the
lingual frenulum
75
what are the functions of the tongue?
movement of food
taste
speech
76
what part of the tongue is important to taste?
anterior portion
77
what are the 3 major pairs of salivary glands?
parotid gland
submandibular gland
sublingal glands
78
What are the parotid glands?
largest of the glands they produce a serous secretion
79
where are the parotid glands found?
anterior to the ears
80
Where do the parotid secretions enter?
over the 2nd upper molar
81
What pathology is associated with the parotid glands?
the mumps, a viral infection that leads to swelling of the glands
82
what are the submanidibular glands?
found under the mandible they produce a serous secretion
83
where do the submandibular secretions enter?
adjacent to the lingual freenulum
84
what are sublingal glands?
found under the tongue producing a mucus secretion
85
where does the sublingual secretion enter?
numerous locations
86
What are the functions of the salivary glands
secretion of saliva
87
what type of glands are the parotid, submandibular and sublingual glands?
exocrine glands
88
Saliva is 99.5% water and is under control by the
nervous system
89
what are the functions of saliva
```
dissolving food
lubrication
stimulation of tastebuds
bacterial prevention
contains enzymes important in digestion of carbs
```
90
taste buds are a type of
chemioreceptor
91
How does saliva prevent bacteria to enter the mouth?
lysozymes
92
What is the mechanical digestion of the mouth?
mastication
93
what is the purpose of mastication?
to increase surface area allowing more digestive enzymes to come into contact with the food
94
what is the result of the actions of the teeth and the tongue?
a bolus is formed
95
what is a bolus?
a soft, round ball of food
96
What chemical digestion occurs in the mouth?
salivary amylase
97
what is salivary amylase?
a special enzyme that begins to break down carbohydrates
98
Salivary amylase breaks:
polysaccharides into disaccharides
99
salivary amylase is primarily produced by
submandibular glands
100
what is the optimal temperature for salivary amylase
98.6
101
what is the optimal pH of salivary amylase?
7
102
what is the optimal pH of lingual lipase?
5
103
does the mouth have ingestion?
yes
104
does the mouth have secretion
yes, saliva
105
does the mouth have motility?
yes mastication
106
what chemical digestion occurs in the mouth?
salivary amylase
107
what mechanical digestion occurs in the mouth?
mastication
108
does absorption occur in the mouth?
no
109
does elimination occur in the mouth?
no
110
what occurs after the bolus is formed?
deglutition
111
what is deglutition?
swallowing
112
when deglutition occurs the bolus is pushed:
into the pharynx with the help of peristalsis.
113
After the bolus enters the pharynx it continues to
the esophagus
114
What covers the larynx?
epiglottis
115
what is the function of the epiglottis?
prevents food and water from entering as the bolus passes
116
does ingestion occur in the pharynx?
no
117
does secretion occur in the pharynx?
no
118
does motility occur in the pharynx?
yes--deglutition
119
what mechanical digestion occurs in the pharynx?
deglutition
120
what chemical digestion occurs in the pharynx?
salivary amylase
121
does absortion occur in the pharynx?
no
122
does elimination occur in the pharynx?
no
123
what is the esophagus?
a collapsible, muscular tube that connects the pharynx to the stomach
124
where is the esophagus located?
the mediastinum of the thorax
125
As the bolus moves from the pharynx into the esophagus it will pass through a sphincter called
the upper esophageal sphincter
126
what is a sphincter?
circular muscle that can constrict an opening regulating movement of the digestive contents through the GI tract
127
the esophagus will go through the
diaphram
128
what is the diaphragm?
a large muscle that seperates the thoracic cavity at an opening called the esophageal hiatus
129
what is a hiatal hernia?
when the esophageal hiatus causes a weakness in the diaphragm and portions of abdominal organs protrude into the thoracic cavity
130
the esophagus eventually narrows and the bolus passes through the _________ to the stomach
lower esophageal sphincter or cardiac sphincter
131
what is peristalsis?
involuntary smooth muscle contractions that push food down
132
peristalsis is under control by the
medulla oblongata
133
does the esophagus have ingestion
no
134
does the esophagus have secretion
mucus
135
does the esophagus have motility?
peristalsis
136
what chemical digestion occurs in the esophagus?
salivary amylase
137
what mechanical digestion occurs in the esophagus>
peristalsis
138
does absorption occur in the esophagus?
no
139
does elimination occur in the esophagus?
no
140
the stomach is shaped like a
j
141
where is the stomach located?
under the diaphragm primarily on the left side
142
what are the four areas of the stomach?
cardiac region
fundus
body
pylorus
143
where is the cardiac region of the stomach?
surrounds lower esophageal sphincter
144
what is the fundus?
the rounded portion of the stomach
145
what is the body portion of the stomach?
large central portion
146
where is the pylorus?
most inferior portion of the stomach, right around the pyloric sphincter
147
what does the pyloric sphincter connect?
the stomach and the small intestine
148
what is the histology of the stomach?
arranged in large folds called the rugae
149
when empty, the stomach is the size of
a clenched fist
150
the stomach can hold up to
4 liters
151
what do mixing waves do?
they push the bolus around causing it to be mixed with digestive enzymes
152
The mixing waves eventually turn the bolus into
chyme
153
mixing waves are a type of
mechanical digestion
154
the stomachs pH is usually around
2
155
How much secretion occurs in the stomach?
2-3 liters
156
why is the stomach so acidic?
the secretion of hydrochloric acid by parietal cells
157
Hydrochloric acid is important because
it maintains optimal pH for digestive enzymes and kills bacteria
158
Hydrochloric acid deactivates
salivary amylase due to the change of pH
159
what is pepsin?
an enzyme that is secreted into the stomach lumen by chief cells
160
what is the function of pepsin?
digestion of proteins
161
how does pepsin digest proteins?
reduces the length and changes the shape of amino acid chains
162
pepsin is secreted in the inactive form called
pepsinogen
163
what activates pepsinogen into pepsin?
the presence of hydrochloric acid
164
what is gastric lipase?
enzyme produced by chief cells that digests lipids
165
what is the optimal pH of gastric lipase?
5-6
166
what is mucus?
alkaline substance that is produced by mucous cells in the stomach lining
167
what is the function of mucus?
moistens the bolus and offers protection to the lining of the stomach
168
what is gastrin?
hormone of the stomach (not an enzyme) produced by endocrine cells
169
what is the function of gastrin?
relaxation of the pyloric sphincter after a meal and release of HCL and pepsinogen
170
what is histamine?
hormone produced by endocrine cells that affects H2 receptors on parietal cells
171
what is intrinsic factor?
a glycoprotein that is secreted by parietal cells
172
what is the function of intrinsic factor?
allows for the absorption of B12 needed for production of RBCs.
173
Can people live without a stomach?
yes but they needed to eat smaller meals more frequently.
174
what is the biggest problem with people who have no stomach?
anemia
175
what is anemia?
a decrease of RBCs
176
How is anemia treated??
B12 shots taken exogenously
177
where do most secretions come from?
the stomach
178
parietal cells are responsible for
hydrochloric acid production
| intrinsic factor
179
what are chief cells responsible for?
pepsinogen
| gastric lipase
180
what are endocrine cells responsible for
histamine and gastrin
181
what are mucous cells responsible for?
making mucus
182
Are carbs digested in the stomach?
no only proteins
183
what are the three phases to stomach digestion?
cephalic phase
gastric phase
intestinal phase
184
what is the cephalic phase?
the smell and thought of food
| chewing (small quantity of histamine and gastrin are released) (HCL/pepsin)
185
what is the gastric phase?
the stomach expands and activates a mechanoreceptor.
186
what is released during the gastric phase?
a large amount of histamine and gastrin producing a large amount of HCL and pepsin
187
what is the intestinal phase?
small intestine. chyme has now left the stomach and stomach has turned off. small intestine turns on.
188
what is released in the intestinal phase?
secretin
cholecystokinin
gastric inhibitory polypeptide
189
most absorption occurs in the
small intestine
190
what things can go through the stomach wall?
water
electrolytes
some drugs
alcohol
191
within 2-6 hours after eating the stomach has emptied its contents into the
duodenum though the pyloric sphincter
192
does ingestion occur in the stomach?
no
193
does secretion occur in the stomach?
2-3 liters mostly mucus
194
does motility occur in the stomach?
`peristalsis and mixing waves
195
does mechanical digestion occur in the stomach?
peristalsis and mixing waves
196
does chemical digestion occur in the stomach?
pepsin and gastric lipase
197
does absorption occur in the stomach?
water, electrolytes, some drugs and alcohol
198
does elimination occur in the stomach?
no
199
what are the three regions of the small intestine?>
duodenum
jejunum
ileum
200
what are the accessory structures of the small intestine?
pancreas
liver
gall bladder
201
where does majority of digestion occur
small intestine
202
As chyme leaves the stomach it passes through the duodenum and comes in contact with material from
pancreas
gall bladder
liver
203
the pancreas is both
exocrine and endocrine organ
204
the endocrine portion of the pancreas is responsible for
homeostasis
205
the exocrine portion of the small intestine is responsible for
digestive enzymes
206
________ make up the exocrine glands of the pancreas
acini cells
207
acini cells secrete
pancreatic juice that contains many digestive enzymes
208
the pancreatic juices will be secreted into the
pancreatic duct and the accessory duct
209
what is pancreatic juice?
clear, colorless secretion composed of water, electrolytes, and enzymes
210
what is the pH of pancreatic juice?
7.2-8.2
211
what is significant of the pH of pancreatic juice?
stops the action of pepsin and activates gastric lipase
212
what enzymes are in pancreatic juice?
```
pancreatic amylase
trypsin
chymotrypsin
procarboxypeptidase
pancreatic lipase
ribonucleases
deoxyribonuclease
```
213
what is pancreatic amylase?
continues digestion of carbohydrates that was started in the mouth
214
what is the function of pancreatic amylase?
turns polysaccharides into disaccharides
215
what is trypsin, chymotrypsin and procarboxypeptidase?
enzymes secreted in inactive form and are activated by enterokinase
216
what is pancreatic lipase?
continues the digestion of lipids
217
what is the function of ribonucleases and deoxyribonucleases?
digestion of nucleic acids
218
what is pancreatitis?
inflammation of the pancreas. It overproduces enzymes causing damage to DNA. The pancreas begins eating itself
219
what is the treatment for pancreatitis?
no eating or drinking
220
what are the endocrine functions of the pancreas?
secretes the hormones glucagon and insulin
221
what are glucagon and insulin important for?
maintaining the level of glucose in the blood
222
where are glucagon and insulin produced?
islet of langerhans
223
what is the islet of Langerhans composed of?
alpha and beta cells
224
what are alpha cells?
produce glucagon when glucose levels in blood decrease
225
how does glucagon work?
travels to the liver and causes glycogenolysis. Glucose is released into the blood maintaining homeostasis
226
what is glycogenolysis?
breakdown of glucogen into glucose
227
what are beta cells?
they produce insulin when blood glucose levels increase.
228
how does insulin work?
it travels to the liver and causes glycogenesis. It also increases the permeability of the cell membrane to glucose allowing passage of glucose into the cell and out of the blood
229
what is glycogenesis?
converting glycogen into glucose
230
what is diabetes mellitus?
inability of the body to produce insulin, produce active insulin, or failure of the receptors to work properly.
231
what is the diagnosis of diabetes?
fasting hyperglycemia, glucosaria
232
what are the symptoms of diabetes>
PU/PD/PP
233
what is PU?
polyuria--constantly urinating
234
what is PD?
polydipsia--constantly drinking
235
what is PP?
polyphagia--constantly eating
236
what are the three types of diabetes?
type 1
type 2
gestational
237
what is type one diabetes?
juvenile onset
insulin dependent
diagnosed in children
238
what is type 2 diabetes?
adult onset
associated with the obese
non insulin dependent
a resistance to insulin
239
what is gestational diabetes?
pregnancy
| good prenatal care can fix it
240
Where is the liver located?
under the diaphram
241
what are the four lobes of the liver?
right
left
caudate
quadrate
242
what holds the liver in place?
falciform ligament (attaches to the diaphragm
243
what is the liver composed of
heptatic lobules containing hepatocytes
244
what are the spaces inside the liver called?
sinusoids
245
How does blood flow into the sinusoids?
blood vessels
246
The sinusoids are lined with
kupffer cells
247
what are kupffer cells?
phagocytic cells that destroy old RBCs, WBCs, bacteria, viruses and toxic materials
248
what are the main functions of the liver?
carbohydrate metabolism
lipid metabolism
protein metabolism
production of bile
249
what are some minor functions of the liver
detoxification
storage
protection
synthesis
250
what is carbohydrate metabolism of the liver?
maintains the normal blood glucose level with help of glucagon and insulin
251
The liver is the main site of
glycogenesis and glycogenolysis
252
what is lipid metabolism of the liver?
storage of triglycerides and production of cholesterol
253
what is protein metabolism of the liver?
converts ammonia into urea which is excreted by the kidneys
254
without the liver a person would
die in a few days because of ammonia poisoning
255
what is bile?
a greenish-brown substance that contains bile salts, bile pigments, cholesterol and fats
256
bile is produced by
the liver
257
bile is stored in the
gallbladder
258
what is the function of bile?
emulsifies fats when released into the duodenum. allows bilirubin to pass out of the body, neutralizes pH in the deuodenum along w/pancreatic juices
259
what gives feces its brownish color?
bile
260
a large portion of bile is reabsorbed in
the small intestine
261
what is bilirubin?
waste product of hemoglobin from old red blood cells
262
what is detoxification of the liver?
removal of some drugs and alcohol from the liver
263
what is stored in the liver?
glycogen, vitamins, minerals and iron
264
what is the protective function of the liver?
phagocytosis by kupffer cells
265
what do kupffer cells phagocytize in the liver?
old RBCc and WBCs
266
what does the liver synthesize?
albumin, heparin and clotting factors are all made in the liver
267
albumin attracts
water
268
what is jaundice?
yellowing of the skin and eyes
269
what is the cause of the yellowing of the eyes?
a buildup of bilirubin
270
what is cirrhosis?
widespread destruction of the liver cells by viral infections, drugs and alcohol
271
with cirrhosis, what happens to liver cells?
they die and aren't reproduced as fast as scar tissue does
272
what is hepatitis?
inflammation of the liver. five different types
273
what is hepatitis A?
fecal oral transmission, vaccines available and usually does not turn into cirrhosis
274
what is hepatitis B?
transmitted by bodily fluids. most common of hep viruses
| vaccine available
275
what is hepatitis C?
transmitted through bodily fluids. healthcare workers at most risk
276
what is the treatment for hepatitis c
prednisone and interferon
277
what is the gallbladder?
sac-like structure that is under the inferior surface of the liver
278
what does the gallbladder do?
stores and concentrates bile
279
what are gallstones?
bile becomes so concentrated that it crystallizes and blocks the ducts of the gallbladder
280
what causes gallstones?
cholesterol precipitation
281
what is the treatment for gallstones?
surgery
medication
sound waves
282
The liver has hepatic ducts that combine to form
common hepatic duct
283
the common hepatic duct combines with the gallbladders cystic becoming the
hepatopancreatic ampulla
284
the hepatopancreatic ampulla empties into the duodenum through an opening called
major duodenal papilla
285
the _____ opens allowing contents to enter the duodenum
sphincter of oddi
286
the accessory pancreatic duct empties into the duodenum through the
minor duodenal papilla
287
what is the stimulus to empty the gallbladder?
chloecystokinen
288
When no digestion is occuriing, the major duodenal ampula is closed and the released bile backs up into
the cystic duct into the gallbladder where it is stored
289
the major stimulus for contraction of the gallbladder and relaxation of the ampulla is
chloecistokinen
290
what is chloecistokinen?
intestinal hormone released when fatty chime enters the duodenum
291
The small intestine is the major site for
absorption and digestion
292
what are the three sections of the small intestine?
duodenum
jejenum
ileum
293
what is the largest portion of the small intestine?
ileum
294
the ileum contains lymphatic tissue called
peyers patch
295
where in the ileum is the peyers patch found?
submucosa
296
the ileum joins the small intestine at the
ileocecal valve
297
what is total transit time for the small intestine?
3-5 hours
298
where does 90% of absorption occur?
small intestine
299
why is the small intestine well suited for absorption?
increased surface area
300
what are plicae circularis?
large folds found in the walls of the small intestine similar to rugae of the tongue
301
the surface of the small intestine is lined with
villi
302
what are villi?
finger-like projections that extend into the lumen
303
what is the function of villi?
to increase surface area
304
On the surface of the small intestine lumen there are
microvilli
305
Microvilli are referred to as
the brush border
306
what mechanical digestion occurs in the small intestine?
segmentation
| peristalsis
307
what is segmentation?
localized contractions that mix the chime with the digestive juice
308
what chemical digestion occurs in the small intestine
the brush border enzymes
309
what are the brush border enzymes>
disaccharidases
| peptidases
310
what are disaccaridases responsible for?
finishing the digestion of carbohydrates by breaking down disaccharides into monosaccharides
311
what are some examples of disaccharidases?
maltase
lactase
sucrase
312
what is lactose intolerance?
individual fails to produce lactase and cannot digest lactose
313
what are the symptoms of lactose intolerance?
```
gas
cramping
diarrhea
pain
fluid retention
```
314
what are peptidases?
enzymes that finish the digestion of proteins down into amino acids
315
carbohydrates are absorbed as
monosacharides
316
how are carbohydrates absorbed?
enter the free end of the epithelial cells, pass through the cytoplasm, pass into a blood capillary and finally enter the hepatic portal vein. From there, they go to the liver and then to the rest of the body
317
proteins are absorbed as:
amino acids
318
how are proteins absorbed>
they follow the same routes as carbohydrates
319
nucleic acids are absorbed as
nucleotides
320
how are nucleic acids absorbed?
the same path as proteins and carbohydrates
321
lipids are absorbed as
fatty acids
322
how are lipids absorbed?
fatty acids diffuse from the lumen of the small intestine into the free end of the epithelial cells, go through the basal side and finally pass into a lacteal of the villus
323
what is a lacteal?
a vessel of the lymphatic system that absorbs fat
324
from the lacteal, what happens to the fat?
becomes part of the lymph and will finally pass into the bloodstream.
325
Fat does not go through the
hepatic portal vein
326
most water reabsorption happens in the
small intestine
327
how much water enters the small intestine daily?
9 liters
328
where does most of the water that enters the small intestine come from?
GI secretions
329
after passing through the small intestine, chime is ready to go through the
ileococal sphincter into the large intestine
330
does ingestion occur in the small intestine?
no
331
does secretion occur in the small intestine?
mucus and digestive enzymes
332
does motility occur in the small intestine?
peristalsis and segmentation
333
does mechanical digestion occur in the small intestine
peristalsis and segmentation
334
does chemical digestion occur in the small intestine?>
disaccharidases and peptidase
335
does absortion occur in the small intestine?
YES
336
Does elimination occur in the small intestine?
no
337
what is the transit time of the large intestine?
the longest at 18-24 hours
338
externally, what gives the large intestine its segmentated appearance?
haustra
339
what are haustra?
series of pouches
340
what are the different sections of the large intestine?
cecum
colon
rectum
anal canal
