Brainscape's Knowledge GenomeTM

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


See full index

GUT (DIGESTIVE PHYSIOLOGY : GMH) > Digestive anatomy : structure and function > Flashcards

Digestive anatomy : structure and function Flashcards

The salivary glands The liver The small intestine The stomach The large intestine and colonic motility

1
Q

What are the three major salivary glands?

A

The parotid glands, the submandibular glands, and the sublingual glands

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

What is the function of the salivary glands?

A

To produce saliva (crucial for start of digestion)

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

Where are the parotid glands located?

A

In the front of the ears, beneath the skin, (thorugh the cheek muscle opposite the crown of the 2nd molar teeth)

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

What is the saliva of the parotid glands like?

A

A watery saliva that has enzymes that breakdown carbs

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

What enzyme do parotid glands produce?

A

Amylase

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

What does amylase do?

A

Its an enzyme that breaks down starch into smaller molecules for digestion

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

Where are the submandibular glands located?

A

Under the tongue, they are hook shaped, the duct opens on the sublingual papilla

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

What is the saliva of the submandibular glands like?

A

Thicker saliva that has both enzymes and mucus (mucus= lubricate food and easier swallow)

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

What enzymes do the submandibular glands secrete?

A

Amylase and lipase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q
A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What does lipase do?

A

Helps to breakdown fats

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

What are the sublingual glands located?

A

Under the tongue, lateral to the submandibular

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

What is the saliva of the sublingual glands like?

A

Thin, watery saliva with high concentraction of mucus

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

What enzymes do sublingual glands produce?

A

Lingual lipase

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

What causes salivary gland secretion?

A

Nerve-mediated reflex based on the intentsity and type of stimulation

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

What type of stimulation activates salivary glands?

A

Chemosensory, masticatory or tactile

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is the reflex modulated by and what is an example of that?

A

Nerve signals from other centres in the CNS, this can be seen through hyposalivation at times of anxiety

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

What 2 reflexes increased salivary secretion?

A

the simple reflex and the conditioned reflex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is the 4 functions of salivia

A
  1. lubrication and binding
  2. Solubilization of dry food
  3. Oral hygiene
  4. Initiation of starch digestion
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is a brief summary of the function of the liver?

A

Regulates most chemical levels in the blood and excrets bile, which helps carry away waste products, and blood in stomach passes through the liver to ‘reset it’, also metabolises drugs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

How does bile functions

A

By-products of broken down subtances are excreted into bile or blood, Bile enters the intestine and goes into faeces, blood by-products go through the kidney into urine

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

Where is the liver located?

A

Upper right portion of the abdominal cavity, beneath the diaphragm and on top of the stomachs, right kidney and intestines

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

What supplys blood to the liver (2)?

A
  • Oxygenated blood flows from hepatic artery
  • Nutrient rich blood flows from the hepatic portal vein

(liver holds around 1 pint (13%) of bodys blood supply)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is an overview of the liver anatomy?

A

It consists of 2 main lobes, made up of 8 segments each. With in the segments are lobules that are connected to small ducts that all connect to form the hepatic duct

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What is the common hepatic duct?

A

This transports the bile to the gallbladder and the duodenum via the common bile duct

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

What is the hepatic artery?

A

The main blood vessel that supplies the liver with oxygenated blood

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

What is the hepatic Portal vein?

A

The blood vessel that carries bloods from the GI tract, gallbadder, pancres, and spleen to the liver

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

What is the structure of hepatocytes?

A

All hepatocytes are bordering on sinusoid on one side and a bile canaliculi on the other side.

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

Where is the small intestine located?

A

In the GI tract between the stomach and large intestine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What are the 3 parts of the small intestine?

A

The duodenum, jejunum and ileum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What is the small intestines function?

A

The digestion and absorption of nutrients

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What are the 4 main layers of the small intestine?

A

Mucoas, submucosa, muscularis externa, adventitia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What does the mucosa layer of the small intestine contain?

A

The epithelium, lamina propria and muscularis mucosae

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

WhWhat does the submucosa layer of the small intestine contain?

A

Connective tissue layer (blood vessels, lymphatics, and submucosal plexus)

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

What does the muscularis externa layer of the small intestine contain?

A

2 smooth muscle layers: The outer longitudinal layer and inner circular layer - the myenteric plexus lies between

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What does the adventitia layer of the small intestine contain?

A

Loosely arranged firboblasts and collagen w vessels and nerves through it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

What are some modifications the small intestine has to aid its functions?

A

Muscose and submucosa form folds (plicae) in a circular fashion in lumen, plicae also contain microvilli to increase surface area = increasing absorption

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

What are the cells of the epithelium in the small intestine?

A

Enterocytes, Goblet cells, crypts of lieberkuhn

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

What roles do enterocytes play in the small intestine?

A

they are tall columnar cells which have absorptive functions, containing brush border enzymes on the surface

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

What roles do goblet cells play in the small intestine?

A

Exocrine glands which secrete mucin

41
Q

What roles do Crypts of lieberkuhn play in the small intestine?

A

Glands in the eptielial lining that contain numerous cells like stem cells and enteroendocrine cells

42
Q

What are Paneth cells in the small intestine?

A

secrete protective agents to protect against pathogens (defensins and lysosomes)

43
Q

What are Peyer’s patches in the small intestine?

A

(protective) only found in the ileum they contain mucosa associated lympathatic tissue (MALT) to hold WBCs and lymphocytes

44
Q

What are the four main classes of enteroendocrine cells in the small intestine?

A

I cells, S cells, K cells, Enterochromaffin cells

45
Q

What is the function of I cells (enteroendocrine) in the small intestine ?

A

Cholecystokinin (CCK) is secreted when fat is in the small intestine. CCK stimulates contraction of gallbladder (push bile) and release of pancreatic enzymes.

46
Q

What is the function of S cells (enteroendocrine) in the small intestine ?

A

Secrete Secretin when low pH of chyme in small intestine. Secretin -> inhibts gastric emptying

47
Q

What is the function of K cells (enteroendocrine) in the small intestine ?

A

Secrete Gastric-Inhibitory peptide (GIP) in response to chyme -> it stimulates insulin release

48
Q

What is the function of Enterochromaffin cells (enteroendocrine) in the small intestine ?

A

mechanically stimulated by chyme. Release serotonin to activated cystic fibrosis transmembrane regulators -> secretes Cl-, NA+ ions and H2O

49
Q

What three main substances the small intestine receives?

A

Bile
Pancreatic enzymes
Alkaline juice (HCO3-)

50
Q

What is the Hepatopancreatic ampulla (ampulla of vater)

A

Common bile duct and pancreatic combine to form this which opens into the duodenum, regulated by the sphincter of Oddi

51
Q

How can you tell when the duodenum becomes ‘midgut’

A

The presence of major duodenal papilla

52
Q

What is the stomach responsible for?

A

formation of chyme, synthesis of proteins necessary for vit absorption, microbial defences, and propages the peristaltic reflex

NOT ABSORPTION OF NUTRIENTS

53
Q

What controls the physiological functions of the stomach?

A

Integration of enteric nervous system, parasympathetic nervous system, and secretion of various neurohormonal molecules

54
Q

What are the 4 regions of the stomach?

A

Fundus, cardia, body, and pylorus

55
Q

what do the walls of the stomach consist of?

A

4 tissue layers, same as small intestine, (mucosal layer, submucosa; muscularis externa; and adventitia/serosa)

56
Q

What is the purpose of the gastric wall in the stomach?

A

To aid in the formation of a transient acidic environment (make food into chyme)

57
Q

What can the gastric mucosal layer of the stomach further divide into (3)?

A

The surface epithelium, lamina propria, and muscularis mucosa

forms gastric pits and glands

58
Q

What 6 cells line the gastric glands of the stomach?

A

Surface mucus cells, Parietal cells, Cheif cells, ECL like cells, G cells, D cells

59
Q

What is the function of surface mucus cells in the gastric glands of the stomach?

A

mucus producing cells to act as a barrier against the gastric acid

60
Q

What is the function of parietal cells in the gastric glands of the stomach?

A

Secrete gastric acid into the lumen of stomach through gastric pits , also secrete instrinsic factor

61
Q

What is the function of chief cells in the gastric glands of the stomach?

A

Secrete pepsinogen (inactive until gastric acid) - pepsin digests proteins

Stimulated by cholinergic activity + by Gastrin

62
Q

What is the function of ECL like cells in the gastric glands of the stomach?

A

secrete Histamine when stimulated by gastrin, indirectly increases HCL production bc of histamines direct actions on parietal cells

63
Q

What is the function of G cells in the gastric glands of the stomach?

A

produce gastrin

gastrin increases HCL production

64
Q

How does gastrin increase HCL production

A

2 ways:
- Stimulation of the ECL like cells to release histamine -> potentiates parietal cells
- Direct stimulation of parietal cells

65
Q

What is the function of D cells in the gastric glands of the stomach?

A

secrete inhibitory molecule somatostatin (suppresses release of gastrin)

activated when lumen reaches level of acidity

66
Q

What is the alimentary canal?

A

This long tube of organs makes a pathway for food to travel through the body. It runs from the mouth to the anus

67
Q

What are the 3 movements associated with gastric motility?

A

Peristalic wave
Segmentation
Ancillary movements

68
Q

What layer of the stomach containcs smooth muscle cells?

A

muscularis externa

69
Q

How does the stomach turn bolus into chyme?

A

Though back and forth churning motions by inner oblique layer of muscularis externa

70
Q

What controls when chyme can leave the stomach?

A

The pyloric sphincter

71
Q

What is the peristalic wave of the stomach?

A

Contraction of the longitudinal smooth muscle layer rhythmically

only occurs in a forward motion with relaxation

72
Q

What is the segmentation of the stomach?

A

Contraction of the circular muscle layer rhythmically

“waxing and meaning” pattern of electrical amplitudes -> can slow the speed of chyme progression

73
Q

What is the ancillary movements of the stomach?

A

Stomach relaxation, needed to allow for accumulation of food

occurs thorugh parasympathetic activation of the vagus nerve which inhibits contraction of gastric muscle layer

74
Q

What are the colons main roles?

A

Water absorption and immunity

75
Q

What is absorption in the colon regulated by?

A

Neuroendocrine mechanisms:
Aldosterone + Glucocorticoids and somatostatin

76
Q

What does aldosterone do in the colon?

A

Increased net absorption of water through stimulation of basolateral sodium potassium ATPase.

77
Q

what does glucocorticoids and somatostatin do in the colon?

A

Increased net absorption of water through stimulation of basolateral sodium potassium ATPase.

78
Q

What 5 ions/substances facilitate the colon in asborbing water?

A

Sodium, Cholride, Water, Potassium, Vitamins and fats

79
Q

What are the Crypts of Lieberkuhn in the Colon?

A

Contain glands and mucus-porducing goblet cells, protecting the intestinal wall from bacteria + pressure on the walls

80
Q

What are the 2 ways a colon protects itself?

A

Crypts of Lieberkuhn and gastrointestinal lymphoid tissue (GALT)

81
Q

How is water absorbed in the colon?

A

Osmosis
Water diffuses in response to an osmotic gradient established by the absorption of electrolytes. Sodium is actively absorbed in the colon by sodium channels. Potassium is either absorbed or secreted depending on the concentration in the lumen. The electrochemical gradient created by the active absorption of sodium allows for this. Chloride ions are exchanged for bicarbonate ions across an electrochemical gradient.

82
Q

What are the 2 types of movement in the colon?

A

Haustral shuttling and Mass movement

83
Q

What is Haustral shuttling in the colon ?

A

the continous movement of food through the colon by regular contraction

84
Q

What are the pacemaker cells of the colon?

A

they line the walls and send signals to the smooth muscle cells causing them to contract

85
Q

what are haustra?

A

Segements of the large intestine

86
Q

What is mass movement in the large intestine?

A

Occur 1-2 times a day, unifrom perstalic contraction of smooth muscle rapidly moving faeces into rectum -> feeling the urge to defecate

called the gastro-colic reflex

87
Q

Name 2 diseases that related to issues in the GI tract?

A

Ulcerative Colitis and Crohn’s disease

88
Q

What is Ulcerative Colitis?

A

Inflammation of the large bowel, symptoms include bloody diarrhoea, tenesmus, pain and fatigue
(Can only usally occur in colon/rectum)

89
Q

what is Crohn’s Disease?

A

Type of IBD, symptoms include diarrhoea, abdominal pain, fever, and weight loss
(Can occur anywhere in GI tract)

90
Q

What is the function of the rectum?

A

Temporary storage of faeces before defecation

91
Q

What triggers the urge to defecate?

A

Stretch recepotrs from the rectum becoming full

contraction of rectal muscles, relation of internal anal sphincter and an initial contraction of the external anal spincter all contribute to defecation

92
Q

What are the 2 main anal spincheters?

A

Internal and external

93
Q

What is the internal anal spinchtor controlled by?

A

parasympathic fibres which relax involuntarily

94
Q

What is the external anal spincter controlled by?

A

Is is skeletal muscle controled by somatic nerve supply from inferior anal branch of the pudendal nerve (controllable)

95
Q

What is the rectosphicteric reflex?

A

A relaxation of the internal sphincter occuring when the rectum is distended

can be delayed by contration of external spincter

96
Q

What is the process of defecation?

A

Relaxation of external anal sphincter, contraction of abdominal wall muscles, relaxation of pelvic wall muscles
Peristaltic waves then facilitate the movement of faeces through the anal cala

97
Q

What are the 2 main types of laxative?

A

Bulk and stimulant

98
Q

How does a bulk laxative work?

A

Adds fibre to the contents of the intenstine -> increases mass -> stimulates wall to cause peristalsis increasing movement of walls

99
Q

How does stimulant laxatives work?

A

On sensory receptors in the wall of intestine to increase the amount of water and electrolytes being retained in the gut -> causes peristalsis helping to empty bowels

GUT (DIGESTIVE PHYSIOLOGY : GMH) (3 decks)

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