Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

BMS150 Post-MT2 > Physiology and Anatomy: Small Intestine > Flashcards

Physiology and Anatomy: Small Intestine Flashcards

1
Q

3 regions of the small intestine?

A
  • Duodenum (shortest)
  • Jejunum
  • Ileum (longest)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

T/F: The majority of the duodenum is retroperitoneal?

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

The jejunum has large _______

A

Plicae circulares

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

The ileum has many large ________

A

Lymphoid nodules (Peyer’s Patches)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Arterial supply of the first 2/3 of duodenum?

A

Hepatic artery of celiac trunk => superior pancreaticoduodenal art.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What branch of the superior mesenteric artery also supplies the duodenum?

A

Inferior pancreaticoduodenal art.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Arterial supply of the rest of the small intestine?

A

Superior mesenteric artery => jejunal and ileal arteries

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Venous drainage of the intestines?

A

Superior mesenteric (SI, LI, stomach and pancreas) + Splenic vein => portal hepatic vein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Mucosa epithelium?

A

Simple columnar, villi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Where are crypts of Lieberkuhn found?

A

In the mucosa of the duodenum, jejunum, and ileum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What type of glands does the duodenum contain?

A

Brunner’s glands

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Are there any glands in the jejunum and ileum?

A

No

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are plica circulares? What do they do? (3)

A

Folds in mucosa and submucosa
- Enhance absorption
- Increase SA
- Encourage mixing

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Each villus is covered by _______ with core of ______

A

Epithelium; Lamina Propria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is in the connective tissue of villi? (4)

A

Arteriole, venule, capillary network, lacteal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are microvilli and what do they do?

A
  • Projections of apical membrane too small to be seen individually = brush border
  • Greatly increase SA
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Where are goblet cells in the SI and what are they for?

A

Scattered among absorptive cells - secrete mucous to facilitate passage of materials

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What do Paneth cells do? (2)

A
  • Regulate the microenvironment of intestinal crypts
  • Initiate immune response
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Where are I cells? What do they secrete? What is their main function?

A
  • Location: SI/duodenum
  • Hormone: CCK
  • Fun: Pancreatic enz secretion, GB contraction
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Where are S cells? What do they secrete? What is their main function?

A
  • Location: SI
  • Hormone: Secretin
  • Fun: Bicarb and H2O secretion from pancreas, inhibit gastric emptying
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What do D cells secrete?

A

Somatostatin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What do K cells secrete?

A

GIP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Where are L cells? What do they secrete? What is their main function?

A
  • Location: SI
  • Hormone: Peptide YY
  • Fun: Inhibit gastric secretion and motility
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Where are Mo cells? What do they secrete? What is their main function?

A
  • Location: SI
  • Hormone: Motilin
  • Fun: Migrating motor complex
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What does stretch from chyme against the intestinal wall elicit?

A

Concentric contractions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What does the spacing between contractions cause? What is it?

A

Segmentation - chyme from one segment forced into relaxed next = mixes and circulates

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

A powerful wave of contractile activity that travels long distances down the small intestine?

A

Peristaltic rush

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Control of peristalsis can be _____ or ______

A

Nervous or Hormonal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Nervous control of the gut? (3)

A
  • Law of the gut
  • Chyme entering duodenum
  • Gastroenteric reflex initiated by distension
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What is the “law of the gut”? What mediates it?

A
  • Distention in the alimentary canal causes distal parts of the canal to relax and proximal parts to contract (circular muscle)
  • Mediated by ENS
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Hormonal control of peristalsis: Enhanced by…? (3)

A
  • Gastrin
  • CCK
  • Serotonin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Hormonal control of peristalsis: Inhibited by…? (3)

A
  • Secretin
  • Peptide YY
  • Epinephrine
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Requirements for chyme entering the duodenum? (3)

A
  • Food particles must be very small
  • Small volumes of low pH fluid
  • Gradual release
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What is the major organ that regulates the rate of gastric emptying?

A

Duodenum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Nervous control that can inhibit gastric emptying? (2)

A
  • SNS: level of spinal cord
  • ENS: submucosal and myenteric plexuses
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What will nervous control inhibit gastric emptying in response too? (4)

A
  • Change osmolarity in duod.
  • Decrease pH in duod.
  • Distention/irritation of duod.
  • Breakdown products of proteins/FAs
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Substances that elicit CCK release?

A

Fats > peptides > carbs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

What is likely the major paracrine regulator of gastric emptying?

A

CCK

39
Q

Substances that elicit secretin release?

A

low pH > fats, capsaicin, bile acids

40
Q

What kind of impact does secretin have on gastric emptying?

A

Mild impact

41
Q

What major hormone performs the role of “ileal brake”?

A

Peptide YY

42
Q

Substances that elicit peptide YY release?

A

Fats > carbs, amino acids

43
Q

What does Peptide YY do if undigested foods are reaching the distal small intestine?

A

Slows everything down

44
Q

The ileocecal valve protrudes into the _____ of the cecum

A

lumen

45
Q

The ileocecal valve is forcefully ____ when excess ______ builds up in the cecum

A

Closed; pressure

46
Q

What supplies a watery vehicle for absorption of substances from chyme as it comes in contact with villi?

A

Intestinal digestive juices by enterocytes

47
Q

Glands found proximal to Sphincter of Oddi?

A

Brunner’s glands

48
Q

What do Brunner’s glands secrete? What is it in response to?

A

Mucous in response to:
- Tactile/irritating stimuli
- Vagal stimulation
- GI hormones (secretin)

49
Q

Function of Brunner’s glands?

A

Protect duodenal wall from digestion of gastric juices

50
Q

What inhibits Brunner’s glands?

A

Sympathetic stimulation

51
Q

_____ and ______ chemically digest macromolecules in the chyme?

A

Bile and Pancreatic enzymes

52
Q

What does bile digest/do?

A

Emulsification of lipids

53
Q

What do pancreatic enzymes do?

A

Hydrolysis of fats, proteins, carbs into smaller molecules

54
Q

Bile is secreted by the liver by what ducts? What do they join to form?

A

Right and left hepatic ducts => common bile duct

55
Q

What regulates the secretion of bile into the duodenum?

A

Sphincter of Oddi

56
Q

If the Sphincter of Oddi is closed, where is bile stored?

A

Gall Bladder

57
Q

The main pancreatic duct meets the common bile duct where?

A

Ampulla of Vater

58
Q

Digestive enzymes of the pancreas: protein digestion? (4)

A
  • Trypsin
  • Chymotrypsin
  • Elastase
  • Carboxypeptidase
59
Q

Digestive enzymes of the pancreas: carb digestion?

A
  • Pancreatic amylase
60
Q

Digestive enzymes of the pancreas: lipid digestion? (2)

A
  • Pancreatic lipase/co-lipase
  • Phospholipase A2
61
Q

What enzyme is contained in saliva? What is it secreted from?

A

Ptyalin (salivary amylase) - secreted by parotid gland

62
Q

What does ptyalin hydrolyze? What blocks its activity?

A
  • Hydrolyzes starch
  • Inhibited by acid of gastric secretions
63
Q

Most important for digestion of starches?

A

Pancreatic amylase

64
Q

3 major enzymes of the brush border? What do they digest?

A
  • Lactase, Maltase, Sucrase
  • Digest major disaccharides
65
Q

Monosaccharides can be absorbed via what? (2)

A
  • Facilitated diffusion
  • Co-transport via Na+ gradient
66
Q

Digestion of proteins in the mouth?

A

Only mechanical, no enzymatic digestion

67
Q

Digestion of proteins in the stomach? (2)

A
  • HCL: denatures proteins
  • Pepsin: begins process of digestion (can digest collagen)
68
Q

Where does most of protein digestion occur?

A

Duodenum and upper jejunum

69
Q

When proteins/peptides enter the small intestine, what enzymes attack them? (4)

A
  • Trypsin
  • Chymotrypsin
  • Carboxypeptidase
  • Proelastase
70
Q

What activates trypsinogen? => trypsin ?

A

Enterokinase (brush border enzyme) in the lumen

71
Q

What zymogens can trypsin activate? (4)

A
  • Chymotrypsin
  • Pro-elastase
  • Pro-carboxypeptidase
  • Pro-phospholipase A2
72
Q

What does trypsin do after food “runs out”?

A

Digests pancreatic hormones

73
Q

Membrane-bound peptidases that aid in digestion of large peptides to di- and tri-peptides?

A

Brush border peptidases

74
Q

33% of absorption is ____ and 67% is ______

A

Free amino acids; peptides

75
Q

Amino acid absorption? (2)

A

Active transport or secondary transport with Na+

76
Q

Dipeptide or tripeptide absorption? (3)

A
  • Some Na+ dependent
  • Some secondary transport with H+
  • Within cytoplasm of enterocyte, most are hydrolyzed to FAAs
77
Q

Why does digestion of fat present a problem?

A

Not water soluble so tends to accumulate in large droplets = reduced SA

78
Q

Solution to challenge of fat digestion?

A

Emulsify fat droplet into small droplets with amphipathic outer molecule = micelle

79
Q

Amphipathic molecules in bile that help form micelles? (3)

A
  • Lecithins
  • Bile salts
  • Cholesterol
80
Q

Once micelles have been formed, ________ can act on the triglycerides in “interior” of the micelle

A

Pancreatic lipase

81
Q

What does pancreatic lipase need to help it insert into the micelle and activate it?

A

Co-lipase

82
Q

What does pancreatic lipase break triglycerides into?

A

2 FFAs and 2 monoacyl glycerols

83
Q

What happens to lipids after they have been chemically digested and absorbed into the enterocyte?

A

They’re reassembled into triglycerides and other lipids and inserted into chylomicrons

84
Q

Where are chylomicrons built and secreted into?

A
  • Built: enterocyte
  • Secreted: Lymphatic vessels
85
Q

What do the proteins on the outside of the chylomicron help it with?

A

Helps it be delivered to and used by cells throughout body

86
Q

Carbohydrates and amino acids are transported across the __________ of the enterocyte, and diffuse into the capillary loops within the _______

A

Basement membrane; villus

87
Q

Small free fatty acids can diffuse into the blood and be carried by ________

A

Serum proteins

88
Q

Chylomicrons are secreted via ______ into the lamina propria

A

Exocytosis

89
Q

What can malabsorption result in? (3)

A
  • Diarrhea
  • Micronutrient deficiency
  • Macronutrient deficiency
90
Q

Types of malabsorption can be pathophysiologically organized into four major problems…?

A
  • Disturbances in intra- luminal digestion
  • Disturbances in terminal digestion
  • Disturbances in trans-epithelial transport
  • Disturbances in lymphatic transport
91
Q

Celiac disease:
- Intra-luminal digestion?
- Terminal digestion?
- Trans-epithelial transport?

A
  • No
  • Yes
  • Yes
92
Q

Chronic pancreatitis:
- Intra-luminal digestion?
- Terminal digestion?
- Trans-epithelial transport?

A
  • Yes
  • No
  • No
93
Q

Lactose Intolerance:
- Intra-luminal digestion?
- Terminal digestion?
- Trans-epithelial transport?

A
  • No
  • Yes
  • No
94
Q

Gastroenteritis:
- Intra-luminal digestion?
- Terminal digestion?
- Trans-epithelial transport?

A
  • No
  • Yes
  • Yes

BMS150 Post-MT2 (17 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions