Week 11 Flashcards
Digestive System
1
Q
What is the opposite of dehydration synthesis?
A
hydrolysis
2
Q
Does all chemical digestion consist of hydrolysis or dehydration reactions?
A
hydrolysis
3
Q
Carbohydrates include (3)?
A
- sugars
- starch
- glycogen
4
Q
Lipids include (3)
A
- triglycerides (fats and oils)
- phospholipids
- steroids (such as cholesterol, estrogen, and testosterone)
5
Q
_____________ are proteins that help speed up metabolism, or the chemical reactions in our bodies
A
Enzymes
6
Q
The (4) Digestive System Functions
A
- ingestion
- digestion
- absorption
- defecation
7
Q
Where does the chemical breakdown
of protein begins?
A
Stomach
8
Q
What does the stomach deliver to the
small intestine?
A
Chyme
9
Q
What is the name of the internal folds of
the mucosa present when the stomach is
empty?
A
Rugae
10
Q
What are the (7) structures of the stomach mucosa?
A
▪ Simple columnar epithelium dotted by
gastric pits that lead to gastric glands
▪ Mucous cells
▪ Mucous neck cells
▪ Chief cells
▪ Parietal cells
▪ Enteroendocrine cells
▪ Gastric glands
11
Q
What are (4) important macro molecules?
A
- proteins
- carbohydrates
- lipids
- nucleic acids
12
Q
What do mucous cells produce?
A
bicarbonate-rich alkaline mucus
13
Q
The digestive tract consists of what (6) parts?
A
- mouth
- pharynx
- esophagus
- stomach
- small intestine
- large intestine.
14
Q
What are the accessory (6) organs of the digestive system?
A
- teeth
- tongue
- salivary glands
- liver
- gallbladder
- pancreas
15
Q
What are the (3) functions of rugae?
A
- increase surface area for digestion
- can expand the stomach to accommodate a large meal
- tightly compressing the food for churning
16
Q
What glands are both endocrine and exocrine?
A
gastric glands
17
Q
What is the simple columnar epithelium of the mucous of the stomach dotted by?
A
gastric pits
18
Q
Columnar epithelial cells are AKA?
A
mucous cells
19
Q
What are the (4) sections of the stomach in order?
A
- cardia
- fundus
- body
- pylorus
20
Q
What are the (3) layers of the muscularis externa of the stomach?
A
- longitudinal layer
- circular layer
- oblique layer
21
Q
What part of the digestive tract has 3 layers of muscle?
A
the stomach
22
Q
What secrets mucous that is thin, watery, and slightly acidic?
A
The mucous neck cells
23
Q
What secretes mucus that is thick and basic in acidity?
A
The surface epithelium
24
Q
What do chief cells produce?
A
protein-digesting enzymes (pepsinogens)
25
Parietal cells produce (2)?
hydrochloric acid and intrinsic factor
26
What activates pepsinogen into pepsin?
hydrochloric acid
27
Enteroendocrine cells produce?
the hormone gastrin
28
What is needed for vitamin B12 absorption in the small intestine?
Intrinsic factor
29
what are the (3) subdivision of the small intestine in order?
▪ Duodenum
▪ Jejunum
▪ Ileum
30
In our gastric juice, there is (5) things present?
- hydrochloric acid
- pepsin/pepsinogen
- water
- mucous
- intrinsic factor
31
What type of digestion is mostly happening in the small intestine?
Chemical digestion
32
The duodenum receives what (3) things?
- chyme
- pancreatic juice
- bile
33
Most digestion and nutrient absorption occurs in which part of the small intestine?
jejunum
34
What (2) things produce enzymes for the small intestine?
- pancreas
- intestinal cells
35
What are the (4) structural modifications of the small intestine that increase surface area for food absorption?
- microvilli
- villi
- circular folds (plicae circulares)
- increased length
36
Where is the site where most absorption happens in the small intestine that has fingerlike projections?
villi
37
What are the tiny projections of the plasma membrane (that create a brush border appearance) from the small intestine called?
microvilli
38
What are the deep folds of mucosa and submucosa of the small intestine called?
Circular folds (plicae circulares)
39
Between the bases of the villi in the small intestine, there are numerous pores that open into tubular glands called?
intestinal crypts
40
In the small intestine, most absorbed nutrients pass into the blood capillaries, but most lipids are picked up by?
the lacteals
41
What are the (6) parts in order of the large intestine?
- cecum
- ascending colon
- transverse colon
- descending colon
- sigmoid colon
- rectum
42
What type of cells produce alkaline mucus to lubricate the passage of feces in the large intestine?
goblet cells
43
What is it called when the muscularis externa layer is reduced to three bands of muscle in the large intestine?
taeniae coli
44
The teniae coli in the large intestine cause the wall to pucker into pocketlike sacs called?
haustra
45
The liver produces?
bile
46
The gallbladder stores?
bile
47
What are the (3) ducts of the liver?
- the common bile duct
- the cystic duct
- the pancreatic duct?
48
the bile duct is the same as?
the common bile duct
49
the bile duct joins the duct of the
pancreas and forms an expanded chamber called?
the hepatopancreatic ampulla and sphincter
50
During digestion, the contraction which duct reopens and then goes back to the common bile duct?
cystic duct
51
What is the movement of foods from one region of the digestive system to another referred to as?
Propulsion
52
What are (2) muscular movements of propulsion?
- Peristalsis
- Segmentation
53
alternating waves of contraction and
relaxation that squeezes food along the GI tract is what type of propulsion?
Peristalsis
54
What is the movement of materials back and forth to foster mixing in the small intestine called?
Segmentation
55
Is segmentation and peristalsis mechanical or chemical digestion?
Mechanical
56
What type of digestion is just rearranging molecules so they are more spread out?
Mechanical
57
Before food enters the blood, where does it have to enter first?
mucosal cells
58
What are carbohydrates are broken down into?
monosaccharides
59
What are proteins are broken down into?
amino acids
60
What are fats broken down to (2)?
- fatty acids
- glycerol
61
What are (3) disaccharides?
- Lactose
- Maltose
- Sucrose
62
What breaks down disaccharides?
Brush border enzymes
63
Lactose after using lactase turns into (2)?
- galactose
- glucose
64
Maltose after using maltase turns into?
- Glucose
65
Sucrose after using sucrase turns into (2)?
- Glucose
- Fructose
66
What enzyme initiates carbohydrate digestion?
Amylase
67
What breaks up large polypeptides from protein?
Trypsin
68
What separates the proteins chains?
Pepsin
69
Bile does what kind of digestion?
Mechanical digestion
70
unemulsified fat is separated by?
Bile salts
71
Waves of peristalsis occur from ________ to __________ forcing food past the pyloric sphincter
1. fundus
2. pylorus
72
The pylorus meters out what substance into the small intestine?
chyme (3 mL at a time)
73
What is it called when peristaltic waves close the pyloric sphincter, forcing content back into the stomach
Retropulsion
74
The stomach empties in how many hours?
4-6 hrs
75
What (2) factors causes the release of the
hormone gastrin?
- presence of food
- rising pH
76
What does gastrin cause the stomach glands to produce (3)?
* Protein-digesting enzymes
* Mucus
* Hydrochloric acid
77
What plays the major role in the digestion of fats, proteins, and carbohydrates as well as neutralizes acidic chyme?
Pancreatic enzymes
78
Which enzyme neutralizes acidic chyme?
pancreatic enzymes
79
Pancreatic juice has a rich supply of?
bicarbonate
80
(4) pancreatic enzymes?
- Pancreatic amylase
- trypsin
- Carboxypeptidase
- lipase
81
Release of pancreatic juice is stimulated by what (2) things?
▪ Vagus nerve
▪ Hormones
82
What (2) hormones stimulate the release of pancreatic juice?
- secretin
- cholecystokinin (CCK)
83
How are lipids absorbed?
diffusion
84
What hormone causes hepato-pancreatic sphincter to relax?
Cholecystokinin (CCK)
85
What hormone causes the liver to secrete more bile?
Secretin
86
What hormone causes weak contractions of the gallbladder?
vagus nerve
87
Which of the following forms of stimulation would cause the gallbladder to secrete bile (2)?
- Vagus nerve
- Cholecystokinin (CCK)
88
At the end of digestion, most substances are absorbed by what kind of transport
through cell membranes?
Active transport
89
Where is the destination of the building blocks?
Liver
90
How do the building blocks get transported to the liver?
- hepatic portal vein
- lymph
91
What is absorbed in the large intestine?
vitamins K and B
92
Is vitamin K and B broken down by stomach or from good bacteria?
Good bacteria - They digest fiber that the body can't
93
Haustral contractions are most seen where?
The large intestine
94
is the peristalsis in the large intestine sluggish or fast?
Sluggish
95
Mass movements from large intestines are slow, powerful movements
that occur how many times per day?
3 to 4 times per day
96
Defecation occurs with relaxation of which sphincter?
voluntary (external) anal sphincter
97
Foods are oxidized and transformed into what?
Adenosine triphosphate ATP
98
Are calories the same as kilocalories?
Yes
99
What are (3) functions of nutrients?
- growth
- maintenance
- repair
100
What are (4) major nutrients?
- carbohydrates
- lipids
- proteins
- water
101
What are (2) minor nutrients?
- vitamins
- minerals
102
Are nucleic acids major nutrients?
No
103
(2) categories of metabolism?
- catabolism
- anabolism
104
What category of substances are broken down to simpler substances where energy is released?
catabolism
105
What is our body's first choice for making energy (ATP)?
Glucose
106
excessively high levels of glucose
in the blood is referred to as?
hyperglycemia
107
low levels of glucose in the blood is referred to as?
hypoglycemia
108
Carbohydrate Metabolism in order (3)?
1. glycolysis
2. krebs cycle
3. electron transport chain
109
What part of the carbohydrate metabolism harvests the most ATP?
Electron transport chain
110
What part of carbohydrate metabolism occurs in the cytosol?
glycolysis
111
What part of carbohydrate metabolism
splits glucose into two pyruvate molecules?
glycolysis
112
Fats are important for (4)?
- insulating the body
- protecting organs
- building some cell structures (membranes & myelin sheaths)
- Excess dietary fat is stored in subcutaneous tissue (in adipose tissue)
113
Excessive fat breakdown causes blood to becom?
acidic
114
What is a product of amino acid breakdown?
Ammonia
115
when ammonia and carbon dioxide mix together, they produce?
Urea
116
What organ degrades hormones?
Liver
117
What does the liver produce?
- cholesterol
- blood proteins (albumin and clotting proteins)
- bile (gallbladder stores bile)
118
What acids are produced by the body when it breaks down fat for energy?
Ketones
119
If we have high blood sugar, what happens?
Glycogenesis
120
Stored glycogen converted to glucose is referred to as?
Glucogenolysis
121
Amino acids and fats converted to glucose is referred to as?
Gluconeogenesis
122
What (2) things are picked up by the liver?
Fats and fatty acids
123
What are the (2) Functions of cholesterol?
- structural basis of steroid hormones and vitamin D
- Building block of plasma membranes
124
Where is most cholesterol produced?
Liver (85%)
125
Can cholesterol and fatty acids freely circulate in the blood?
No
126
Do LDLs or HDLs transport cholesterol to body cells?
LDLs
127
Do LDLs or HDLs transport cholesterol from body cells to the liver?
HDLs
128
The alimentary canal is a continuous, hollow tube present by which week of development?
5th week
129
Teething begins around what age?
6 months
130
Occurs when small, bulging sacs or pouches form on the inner wall of the intestine is referred to as?
diverticulosis
131
What are the 3 ducts of the liver in order?
1st. Right and left hepatic ducts
2nd common hepatic duct
3rd cystic duct
132
When chyme entering the duodenum, what (2) hormones are secreted?
- Cholecystokinin (CCK)
- Secretin
133
What (2) hormones travel to the pancreas, and causes the secretion of enzyme-rich pancreatic juice?
- Cholecystokinin (CCK)
- Secretin
134
What hormone causes the gallbladder to secrete stored bile?
Cholecystokinin (CCK)
135
What causes the release of pancreatic juice in gallbladder and pancreas?
Vagus nerve
136
In Krebs Cycle, what waste product is being produced?
CO2
