Brainscape's Knowledge GenomeTM

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


See full index

Physiology. Gastrointestinal Physiology. > The Gastric Phase of Digestion. > Flashcards

The Gastric Phase of Digestion. Flashcards

1
Q

What are the 3 regions of the stomach from cranial to caudal?

A

Fundus.

Corpus.

Pylorus.

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

What name is given to the region where the oesophagus joins the stomach?

A

The cardia.

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

What name is given to the region where the stomach joins the small intestine?

A

The pyloric sphincter.

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

What are the 4 main functions of the stomach?

A

Temporary storage of food.

Mixing and grinding of food.

Chemical and enzymatic digestion.

Release of chyme into the intestine.

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

What part of the stomach is responsible for food storage and what animals will mainly store food in the stomach?

A

The fundus.

Carnivores.

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

What nutrients are mainly broken down in the stomach?

A

Proteins and some fats.

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

Does any nutrient absorption occur in the stomach?

A

No.

Only some drugs and water are absorbed in the stomach.

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

Why does the stomach need to store food?

A

So that only small portions are released into the duodenum at any one time.

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

What part of the stomach is responsible for storage?

A

The proximal stomach (the fundus).

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

What reflex allows for the stomach to expand so it can accommodate incoming food?

A

The accommodation reflex.

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

How does the accommodation reflex work?

A

Food entering the stomach triggers mechanoreceptors.

Reduction in muscle tone.

Relaxation and expansion of the stomach.

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

What is the neurotransmitter that leads to the accommodation reflex?

A

VIP or nitric oxide.

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

What will reduce the accommodation reflex?

A

Sympathetic stimulation.

Suppression of reflex stimulation.

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

What feeling does the suppression of the accommodation reflex lead to?

A

Satiety.

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

How long will food stay in the stomach for?

A

1/2 an hour for fluids.

2-4 hours for solid foods.

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

Will larger or smaller species have faster digestion?

A

Smaller species have faster digestion.

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

What happens to the motility of the stomach once food enters?

A

Peristaltic motions push the chyme towards the pyloric sphincter.

When the sphincter is closed food will be pushed back via retropulsion.

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

Will the stomach carry out peristalsis when it is empty?

A

This is called the migrating motility complex and it is designed to clear the stomach.

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

What hormone leads to the migrating motility complex in the stomach?

A

Motilin.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are the 2 types of mucosa that are found in the stomach?

A

Non-glandular/cutaneous mucosa.

Glandular mucosa.

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

What species have a large area of the stomach covered by non-glandular mucosa?

A

Horses.

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

What is the function of the glandular mucosa of the stomach?

A

To secrete substances into the stomach.

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

What are the 3 regions that make up the glandular mucosa of the stomach?

A

A cardiac region.

A parietal region.

A pyloric region.

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

What are the glandular mucosa of the stomach lined with?

A

Gastric pits.

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

What 6 cells are found in the gastric pits of the gastric mucosa?

A

Mucous neck cells.

Parietal cells.

Enterochromaffin like cells.

Chief cells.

D cells.

G cells.

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

What is secreted by the mucous neck cells of the gastric mucosa?

A

Mucous.

Bicarbonate.

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

Why is mucous secreted into the stomach?

A

It protects the stomach lining from the gastric acid.

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

What is secreted by the parietal cells of the gastric mucosa?

A

Gastric acid.

Intrinsic factor.

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

What is secreted by the chief cells of the gastric mucosa?

A

Pepsinogen.

Gastric lipase.

30
Q

What is secreted by the enterochromaffin like cells of the gastric mucosa?

A

Histamine.

31
Q

Why is histamine secreted into the stomach?

A

It stimulates acid secretion.

32
Q

What is secreted by the D cells of the gastric mucosa?

A

Somatostatin.

33
Q

What is the function of the somatostatin that is secreted into the stomach by the D cells?

A

It inhibits acid secretion.

34
Q

What is secreted by the G cells of the gastric mucosa?

A

It secretes gastrin.

35
Q

Why is gastrin secreted into the stomach by the G cells?

A

It stimulates acid secretion.

36
Q

What part of the stomach will G cells be found in?

A

Only in the pylorus.

37
Q

What name is given to the openings of the gastric pits of the stomach?

A

The gastric gland.

38
Q

Will G cells secrete gastrin into the stomach?

A

No, they secrete it into the blood.

39
Q

How do the different cells within the gastric pits communicate with each other?

A

Via paracrine signalling.

40
Q

What is found at the bottom of the gastric pits of the stomach?

A

Stem cells which form new cells.

41
Q

What cells cover the entire glandular mucosa and secrete mucous?

A

Goblet cells.

42
Q

What pH does mucous have?

A

It contains bicarbonate so it alkaline.

43
Q

What controls the secretion of mucous into the stomach?

A

Local reflexes within the enteric nervous system.

Central reflexes via the vagus nerve.

44
Q

Stimulation of mucous secretion via goblet cells will be as a result of what hormone?

A

Prostaglandin.

45
Q

What kind of drugs will affect mucous secretion?

A

NSAID drugs.

These drugs inhibit prostaglandin synthesis and this affects the stomach.

46
Q

What is released into the stomach by the parietal cells?

A

Stomach acid.

47
Q

What are the 5 main functions of gastric acid?

A

Break down ingesta.

Denature proteins.

Emulsify fats.

Turn pepsinogen into pepsin.

Kill microbes.

48
Q

What 3 substances lead to the secretion of gastric acid via the parietal cells?

A

Acetylcholine.

Gastrin.

Histamine.

49
Q

What causes stimulation of gastric acid release via acetylcholine?

A

The central and enteric nervous systems.

50
Q

What causes stimulation of gastric acid release via gastrin?

A

G cells release gastrin following stimulation via arrival of peptides in the stomach.

51
Q

What cells cause stimulation of gastric acid release via histamine?

A

The enterochromaffin cells release histamine.

52
Q

What is the strongest stimulator of gastric acid release?

A

Histamine release.

53
Q

What is the major enzyme that forms gastric acid from its constituents?

A

Carbonic anhydrase.

54
Q

What is exchanged that allows fro parietal cells to secrete acid into the stomach?

A

Hydrogen ions are exchanged for potassium ions.

55
Q

How can over-production of histamine affect the stomach?

A

It can lead to an over secretion of acid.

56
Q

What immune cells commonly produce histamine?

A

Mast cells.

57
Q

What cells are responsible for secreting pepsinogen into the stomach?

A

Chief cells.

58
Q

What is pepsinogen?

A

The inactive form of the enzyme pepsin.

59
Q

What is required to convert pepsinogen into pepsin?

A

An acidic environment.

60
Q

What is the optimum pH for pepsin?

A

Between 1 and 3.

61
Q

What is the function of pepsins?

A

They break down proteins into smaller polypeptides or oligopeptides.

62
Q

Is pepsin secreted in young animals that are still nursing?

A

No, they secrete prochymosin (rennin in calves).

63
Q

What is the function of the intrinsic factor that is secreted by parietal cells?

A

It binds to B12 and prevents it from being digested.

64
Q

What is the major function of B12?

A

It is a major co-factor for erythropoiesis.

65
Q

What are the 3 major reasons why gastric motility needs to be tightly controlled?

A

To prepare the stomach for incoming food.

So the amount of gastric secretions can match the type and quantity of food being digested.

To initiate the secretion of pancreatic enzymes and bile into the small intestine.

66
Q

What phase of digestion will stomach secretions begin in?

A

The cephalic phase.

67
Q

When does the gastric phase of digestion begin?

A

When food enters the stomach.

68
Q

How does the stomach know when food arrives inside it?

A

Mechano and chem receptors are stimulated.

69
Q

What happens once the stomachs receptors are activated following the entry of food?

A

They stimulate nerves and this leads to the relaxation of the stomach.

This also stimulates stomach contractions and secretions.

70
Q

When will gastrin secretion be blocked?

A

When the pH is less than 2.

Physiology. Gastrointestinal Physiology. (6 decks)

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