Bio: Ch 9, 5 Flashcards
(166 cards)
1
Q
intracellular digestion
A
oxidation of glucose and fatty acids to make energy
2
Q
extracellular digestion occurs in…
A
lumen of alimentary canal
3
Q
mechanical digestion
A
physical breakdown of large food particles into smaller food particles
4
Q
chemical digestion
A
enzymatic cleavage of chemical bonds, such as the peptide bonds of proteins or the glycosidic bonds of starches
5
Q
digestive tract pathway
A
oral cavity > pharynx > esophagus > stomach > small intestine >large intestine > rectum
6
Q
accessory organs of digestion
A
salivary glands, pancreas, liver, gallbladder
7
Q
enteric nervous system
A
wall of alimentary canal
controls peristalsis
function independently of brain and spinal cord
8
Q
enteric nervous system
upregulated/downregulated by…
A
upregulated by parasympathetic nervous system
downregulated by sympathetic nervous system
9
Q
extracellular digestion
A
nutrients are obtained fro mfood
10
Q
digestive system
ADH
A
promotes thirst
11
Q
digestive system
aldosterone
A
promotes thirst
12
Q
digestive system
glucagon
A
promote hunger
13
Q
digestive system
ghrelin
A
promote hunger
14
Q
digestive system
leptin
A
promote satiety
15
Q
digestive system
cholecystokinin (CCK)
A
promote satiety
16
Q
which hormones promote thirst
A
ADH and aldosterone
17
Q
which hormones promote hunger
A
glucagon and ghrelin
18
Q
which hormones promote satiety
A
leptin and CCK
19
Q
digestive system
what happens in oral cavity
A
- mastication starts mechanical digestion
- salivary amylase and lipase start chemical digestion
- food formed into bolus and swallowed
20
Q
what/where does mechanical digestion start?
A
oral cavity
mastication
21
Q
what/where does chemical digestion start?
A
oral cavity
salivary amylase and lipase
22
Q
digestive system
esophagus
A
propels food to the stomach using peristalsis
23
Q
what does food enter the stomach through?
A
lower esophogeal (cardiac) sphincter
24
Q
salivary amylase
A
hydrolyzes starch into smaller sugar
25
lipase
catlyzes hydrolysis of lipids
26
digestive system
3 main sources of energy
carbs, fats, proteins
27
parts of stomach
fundus and body - mostly gastric glands
antrum and pylorus - mostly pyloric glands
28
lesser curvature
internal curvature of the stomach
29
greater curvature
external curvature of stomach
30
rugae
folds that line the stomach
31
mucous cells
produce bicarbonate rich mucus to protect the stomach
32
chief cells
secrete pepsinogen
33
pepsinogen
protease activated by the acidic environment of the stomach
34
parietal cells
secrete HCl and intrinsic factor
35
intrinsic factor
needed for vitamin b12 absorption
36
G-cells
secrete gastrin
37
gastrin
peptide hormone
increases HCl secretion and gastric motility
38
gastric glands respond to signals from...
vagus nerve of parasympathetic nervous system
39
stomach secretes 6 products:
1. HCl - kills microbes, denature proteins, converts pepsinogen into pepsin
2. pepsinogen - partially digests proteins
3. mucus - protects mucosa
4. bicarbonate - protects mucuosa
5. water
6. intrinsic factor
40
chyme
food particles after mechanical and chemical digestion in stomach
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food passes into duodenum through...
pyloric sphincter
42
duodenum
first part of small intesting
primarily involved in chemical digestion
43
parts of small intestin:
duodenum, jejunum, ileium
44
hormones and enzymes in duodenum/small intestine
disaccharidases, peptidases (aminopeptidase, dipeptidase), enteropeptidase, secretin, CCK
45
disaccaharidases
brush border enzymes that break down maltose, isomaltose, lactose, and sucrose into monosaccharides
46
brush border peptidases
includes
break down proteins
aminopeptidase, dipeptidase
47
brush border enzymes
present on the luminal surface of cells lining the duodenum
break down dimers and trimers of biomeolcules into absorbable monomers
48
enteropeptidase
activates trypsinogen and procarboxypeptidases
initiating an activation cascade
49
secretin
stimulates release of pancreatic juices into digestive tract
slows motility
50
CCK
stimulates bile release from gallbladder, release of pancreatic juices, and satiety
51
bile
fluid composed of bile salts, pigments, and cholesterol
emulsifiers fats, making them soluble and increasing their surface area
52
bile salts
facilitate chemical digestion of lipids
53
acinar cells
in pancreas
produce pancreatic juices that contain bicarbonate, pancreatic amylase, pancreatic peptidases, pancreatic lipase
54
liver
* produces bile, nutrients, urea
* detoxifies chemicals
* activates or inactivates medications
* synthesizes albumin and clotting factors
55
bile is stored in
gallbladder
56
gallbladder
stores and concentrates bile
57
jejunum and ilium
small intestine
absorption
58
small intestine structure
lined with villi, which are covered with microvilli
increases surface area available for absorption
59
villi structure
contain capillary bed and lacteal
60
lacteal
vessel of lymphatic system
61
small intestine
water soluble compounds such as... enter the...
monosaccharides, amino acids, water soluble vitamins, small fatty acids, water
enter capillary bed
62
small intestine
fat soluble compounds such as... enter the...
fats, cholesterol, fat soluble vitamins
enter the lacteal
63
large intestine
absorbs water ad salts, forming semisolid feces
64
cecum
outpocketing that accepts fluid from the small intestine through the iceocecal valve
site of attachment of the appendix
65
colon parts
ascending, transverse, descending, sigmoid
66
rectum
stores feces that are then excreted through anus
67
gut bacteria produce...
vitamin K and biotin (vitamin B7)
68
Compare the secretion of parietal cells versus chief cells.
Parietal cells and chief cells are both found in the stomach.
Parietal Cells release HCl, whereas Chief Cells release pepsinogen.
69
Which of the following produce a protective coating that prevents the stomach from digesting itself?
(A) Chief Cells
(B) Mucous Cells
(C) Parietal Cells
(D) Beta Cells
(B) Mucous Cells
Mucous Cells release mucin, which coats the stomach to prevent pepsin or HCl from degrading the stomach lining.
70
What converts trypsinogen and chymotrypsinogen into their active forms?
Enteropeptidase converts trypsinogen and chymotrypsinogen into their active forms.
71
Describe how pancreatic lipase and bile work together to break down fats.
Bile emulsifies fats, organizing them into smaller droplets that can be acted on by pancreatic lipase.
72
The duodenum is receiving a lot of chyme from the stomach that is being digested by gastric juice/hydrochloric acid. To neutralize all that acid, the exocrine pancreas secretes which of the following?
(A) H2O
(B) H2SO4-
(C) Cl-
(D) HCO3-
(D) HCO3-
The exocrine pancreas releases bicarbonate, a base, to neutralize the gastric acid.
73
The exocrine pancreas releases many enzymes to aid in digestion. Match the following enzymes to their function.
(1) Amylase
(2) Lipase
(3) Trypsin/chymotrypsin
(A) Break down triglycerides into free fatty acids/ monoglycerides/ diglycerides/ glycerol
(B) Break down starches into smaller carbohydrates
(C) Break down protein into amino acids
(1) Amylase -\>
(B) Break down starches into smaller carbohydrates
(2) Lipase -\> (A) Break down triglycerides into free fatty acids/ monoglycerides/ diglycerides/ glycerol
(3) Trypsin/chymotrypsin -\> (C) Break down protein into amino acids
74
The large intestine's primary responsibility is to absorb:
(A) nutrients
(B) proteins
(C) fatty acids
(D) water
(D) water
The large intestine's primary responsibility is to absorb water.
75
Gastrin will also increase or decrease stomach motility? What does that mean?
Gastrin increases stomach motility, which increases the churning of food by the stomach.
76
When chyme enters the duodenum, the production of which of the following hormones is triggered?
I. Ghrelin
II. Secretin
III. Cholecystokinen
(A) I Only
(B) I and III Only
(C) II and III Only
(D) I, II, and III
(C) II and III Only
When chyme enters the duodenum, the production of secretin and cholecystokinen is triggered.
77
What is the primary role of secretin versus cholecystokinen?
The primary role of secretin is to increase the pH of the chyme as it enters the duodenum.
The primary role of cholecystokinen is to promote digestion in the duodenum.
78
peptide hormones are composed of
amino acids
79
peptide hormones are derived from
larger precursor proteins that are cleaved during posttranslational modification
80
peptide hormones
membranes
polar
cannot pass through plasma membrane
81
peptide hormones
location of receptor
extracellular (cell membrane)
82
peptide hormones
mechanism of action
* stimulates a receptor (usually GPCR)
* affecting levels of second messengers (usually cAMP)
* initiates signal cascade --\> can induce amplification of signal
83
peptide hormones
speed of onset
quick
84
peptide hormones
duration of action
short lived
85
peptide hormones
method of travel in bloodstream
water soluble --\> dissolves and travels freely
86
steroid hormones are derived from
cholesterol
87
steroid hormones are produced by
gonads and adrenal cortex
88
steroid hormones
location of receptor
intracellular or intranuclear
89
steroid hormones
mechanism of action
* binds to a receptor
* induces conformational change
* regulates transcription at the level of the DNA
90
steroid hormones
method of travel in bloodstream
lipid soluble --\> cannot dissolve in blood stream --\> binds to carrier protein
91
steroid hormones
speed of onset
slow
92
steroid hormones
duration of action
long lived
93
steroid hormones
membrane
minimally polar --\> can pass through membrane
94
amino acid hormones are derived from
amino acids
95
amino acid hormones
features
variable
96
amino acid hormones
exs
epinephrine, norepinephrine, triiodothyronine, thyroxine
97
catecholamines
mechanism of action
duration and speed of onset
bind to GPCR
usually fast and shortlived
98
catecholamines exs
epinephrine, norepinephrine
99
thyroid hormones
mechanism of action
bind intracellularly
100
direct hormones
secreted then act directly on a target tissue
have major effects on nonendocrine tissues
101
tropic hormones
require intermediary to act
have major effects on other endocrine tissues
102
peptide and amino acid derivative hormone
end in
-in or -ine
103
steroid hormones
end in
-one, -ol, -oid
104
anterior pituitary releases hormones in response to stimulation from
hypothalamus
105
anterior pituitary
hormones
FLAT PEG
* 4 tropic hormones (FLAT)
* FSH, LH, ACTH, TSH
* 3 direct hormones (PEG)
* prolactin, endorphins, growth hormone
106
follicle stimulating hormone (FSH)
released by anterior pituitary
promotes the development of ovarian follicles in females and spermatogenesis in males
107
lutenizing hormone (LH)
released by anterior pituitary
promotes ovulation in females and testosterone production in males
108
adrenocorticotropic hormone (ACTH)
released by anterior pituitary
promotes the synthesis and release glucocorticoids from the adrenal cortex
109
thyroid stimulating hormone (TSH)
released by anterior pituitary
promotes the synthesis and release of triiodothyronine and thyroxine from the thyroid
110
prolactin
released by anterior pituitary
promotes milk production
111
endorphins
released by anterior pituitary
decrease perception of pain and can produce euphoria
112
growth hormone (GH)
released by anterior pituitary
promotes growth of bone and muscle and shunts glucose to these tissues
raises blood glucose concentrations
113
posterior pituitary releases ___ hormones produced in the \_\_\_\_
2
hypothalamus
114
posterior pituitary
hormones
ADH and oxytocin
115
antidiuretic hormone (ADH or vasopressin)
released by posterior pituitary
secreted in response to low blood volume or increased blood osmolarity
increases reabsorption of water in collecting duct of nephron, increasing blood volume, and decreasing blood osmolarity
116
oxytocin
released by posterior pituitary
secreted during childbirth and promotes uterine contractions
positive feedback loop
117
negative feedback
hormone later in pathway inhibits hormones earlier in the pathway
118
hypophyseal portal system
blood vessel system that directly connects the hypothalamus with anterior pituitary
119
thyroid
hormones
triiodothyronine (T3) and thyroxine (T4)
calcatonin
120
T3 and T4 produced by
follicular cells
121
T3 and T4
released by thyroid
* contain iodine
* increase basal metabolic rate and alter the utilization of glucose and fatty acids
* required for proper neurological and physical development in children
122
calcitonin
released by thyroid
* decreases plasma calcium concentration by promoting calcium excretion in the kidneys
* decreases calcium absorption in the gut
* promotes calcium storage in bone
123
parathyroid glands release
parathyroid hormone
124
parathyroid hormone
released by parathyroid glands
* decreases excretion of calcium by the kidneys
* increases bone resorption directly to increase blood calcium conc
* activates vitamin D
* promotes resorption of phosphate from bone
* reduces reabsorption of phosphate in the kidney
* vitamin D promotes absorption of phosphate from gut - cancel out
125
vitamin D
necessary for calcium and phosphate absorption from the gut
126
adrenal cortex
hormones
* glucocorticoids (cortisol and cortisone)
* mineralocoriticoids (aldosterone)
* cortical sex hormones (androgens and estrogens)
127
glucocorticoids
| (cortisol and cortisone)
released from adrenal cortex
* increase blood glucose concentration
* reduce protein synthesis
* inhibit immune system
* participate in stress reponse
128
glucocorticoid (cortisol and cortisone) release stimulated by
ACTH
129
mineralocorticoids (aldosterone)
produced by adrenal cortex
promote sodium readsorption in distal convoluted tubule and collecting duct --\> increases water reabsorption
130
aldosterone
produced by adrenal cortex
increases potassium and hydrogen ion excretion
131
aldosterone activity is regulated by
renin-angiotensin-aldosterone-system
132
adrenal medulla
hormones
catecholamines (epinephrine, norephinephrine)
133
catecholamines
secreted by adrenal medulla
* promote glycogenolysis
* increase the basal metabolic rate
* increase heart rate
* dilate bronchi
* alter blood flow
134
pancreas
hormones
regulate glucose homeostasis
glucagon, insulin, somatostatin
135
glucagon produced by
alpha cells in pancreas
136
insulin produced by
beta cells in pancreas
137
somatostatin produced by
delta cells in pancreas
138
glucagon
hormone
produced by pancreas
raises blood glucose levels by stimulating protein and fat degradation, glycogenolysis, and gluconeogensis
139
insulin
hormone
produced by pancreas
lowers blood glucose levels by stimulating glucose uptake by cells and promoting anabolic processes like glycogen, fat, and protein synthesis
140
somatostatin
hormone
produced by pancreas
inhibits insulin and glucagon secretion
141
testes secrete
testosterone
142
ocaries secrete
estrogen and progesterone
143
pineal gland releases
melatonin
144
melatonin
regulates circadian rhythms
145
stomach and intestine produces
secretin, gastrin, CCK
146
kidneys secrete
erythropoitin
147
erythropoietin
secreted by kidneys
stimulates bone marrow to produce erythrocytes in response to low oxygen levels in the blood
148
heart's artria secrete
atrial natriuretic peptide (ANP)
149
atrial natriuretic peptide (ANP)
secreted by atria
promotes excretion of salt and water in kidneys in response to stretching of atria (high blood volume)
150
thymus secretes
thymosin
151
thymosin
secreted by thymus
important for proper t-cell development and differentiation
152
GnRH causes \_\_hormone\_\_ to be released
FSH and LH
153
GHRH causes \_\_hormone\_\_ to be released
GH
154
TRH causes \_\_hormone\_\_ to be released
TSH
155
corticotropin-releasing factor causes \_\_hormone\_\_ to be released
ACTH
156
gigantism
excess of GH
157
dwarfism
deficit of GH
158
hypothyroidism
deficiency of iodine
159
hyperthyroidism
excess of thyroid hormone
160
glucagon is released when glucose levels are \_\_\_
low
161
insulin is secreted when glucose levels are \_\_\_
high
162
hypoglycemia
excess insulin
low blood glucose concentration
163
hyperglycemia
excess blood glucose concentration
164
polyuria
increased frequency of urination
165
polydipsia
increased thirst
166
