Brainscape's Knowledge GenomeTM

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


See full index

Biomedical Physiology > The Digestive System > Flashcards

The Digestive System Flashcards

1
Q

What is the largest endocrine organ in the body?

A

The digestive system, although there are cells scattered throughout the GIT

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

Ingested food is obviously an energy

A

source

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

Ingested food is digested and absorbed, what happens to the simple molecules obtained

A

they travel into cells via the circulatory system

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

*Label the following organs of the gastrointestinal tract

A

there ya go

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

What are the four digestive processes

A

motility, secretion, digestion and absorption

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

Of the four digestive processes, we have motility, what type of muscle makes up the motility parts?

A

Smooth muscle

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

Smooth muscle makes up the motility process of digestion, why is this?

A

Because it is involuntary

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

Although the smooth muscle in the walls of the digestive tract is phasic smooth muscle, it also maintains a constant low level of contraction, what is this called?

A

It is called tone

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

What is phasic digestive motility?

A

Phasic smooth muscle that displays action potential induced bursts of contraction

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

What are the two types of movement that come under phasic digestive motility?

A

Propulsive movements and mixing movements

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

One of the four processes making up digestion is phasic digestive motility, describe propulsive movements

A

Propelling or pushing the contents forward through the digestive tract with the rate of propulsion varying depending on the function accomplished by the different regions

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

Where would the rate of phasic digestive motility, propulsive movements be quickest and why?

A

In the oesophagus because the structure merely serves as a passageway from the mouth to the stomach

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

Where would the rate of phasic digestive motility, propulsive motion be slowest and why?

A

In the small intestines because it allows time for the breakdown and absorption of food

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

Mixing, a type of phasic digestive motility serves a twofold function, what is this?

A

Firstly, it mixes food with digetive juices, these movements promote digestion of the food. Secondly, they facilitate absorption by exposing all parts of the intesitnal contents to the absorbing surfaces of the digestive tract

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

Mixing occurs in both the small and large intestine, where would it occur at a slower rate?

A

In the large intestine

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

One of the four digestive processes involves secretion, what two types of secretion may occur

A

endocrine and exocrine

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

Where does endocrine secretion take place

A

cells are scattered throughout the GIT - gi hormones and gi peptides

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

where does exocrine secretion take place

A

cells in the lining of the git and accessory digestive organs

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

what is the difference between endocrine and exocrine gland secretions?

A

Generally speaking, exocrine glands are duct glands i.e;these glands are provided with ducts to transport their secretions.Eg:-salivary glands,pancres etc; Whereas Endocrine glands are ductless glands i.e;they release their secretions directly into blood stream.

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

what is one of the four processes of digestion, digestion itself?

A

Digestion is the chemical breakdown of food stuffs, by enzymatic hydrolysis

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

what is enzymatic hydrolysis?

A

Enzymatic hydrolysis is a process in which enzymes facilitate the cleavage of bonds in molecules with the addition of the elements of water.

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

what is one of the four processes involved in digestion, absorption about?

A

small units being transferred from the GIT lumen to the blood or the lymph

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

The gastrointestinal tract is made of four layers, name these four layers

A
  1. Mucosa
  2. Submucosa
  3. Muscularis externa
  4. Serosa
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What does the mucosa line?

A

The luminal surface

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

What is the function of the mucosa?

A

It has a protective function

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

There are regional differences in the mucosa in various parts of the GI tract, what are these and why?

A

Some areas of the GI tract have mucosa which has greater folding because they require a larger surface area

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

What is the submucosa?

A

A layer of connective tissues

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

Name two vessels present in the submucosa connective tissue

A

Blood and lymph vessels

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

What nerve plexus is found in the submucosa and what is it called?

A

The submucosal plexus

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

What is the muscularis externa made of?

A

A smooth muscle layer

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

The smooth muscle layer making up the muscularis externa is made of two muscle layers, what are these?

A

The inner circular layer and the outer longitudinal layer

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

What is the function of the inner circular layer

A

to contract to decrease diameter

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

what is the function of the outer longitudinal layer

A

to contract to decrease length

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

What movements do the muscles in the muscularis externa aid in

A

propulsive and mixing movements

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

There is a nerve plexus found in the muscularis externa which is the third layer of the GI tract, what is it called?

A

The myenteric plexus

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

what is a nerve plexus?

A

A nerve plexus is a plexus (branching network) of intersecting nerves. A nerve plexus is composed of afferent and efferent fibers that arise from the merging of the anterior rami of spinal nerves and blood vessels.

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

what is the serosa?

A

a connective tissue layer

38
Q

what does the serosa layer of the GI tract secrete?

A

serous fluid

39
Q

what is the serosa, being one of the layers of the GI tract continous with?

A

The mesentary

40
Q

what is the mesentary?

A

a fold of the peritoneum which attaches the stomach, small intestine, pancreas, spleen, and other organs to the posterior wall of the abdomen.

41
Q

the regulation of digestive function involves four factors, what four factors are these?

A
  1. autonomous smooth muscle function
  2. intrinsic nerve plexuses
  3. extrinsic nerves
  4. gi hormones
42
Q

GIT smooth muscle undergoes rhythmic depolarisations/repolarisations under autonomous smooth muscle function, what self induced cells allow this to happen?

A

The interstitial cells of Cajal

43
Q

What are the interstitial cells of Cajal and what do they resemble?

A

They are pacemaker cells, like self excitable cardiac muscle cells

44
Q

What is the function of the interstitial cells of Cajal

A

They are pacemaker cells that display rhymthmic spontaneous variations in the membrane potential

45
Q

What is the prominent type of self induced electrical activity in the digestive smooth muscle?

A

Slow-wave potentials, also referred to as the diestive tract’s basic electrical rhythm, BER

46
Q

The electrical activity under autonomous smooth muscle control spreads from cells by what?

A

gap junctions

47
Q

The sheets of muscles which are under basic electrical rhythm act as one unit, what is this called?

A

functional synctium

48
Q

BER produces slow waves and not action potentials but if the threshold potential is reached what happens?

A

Action potentials are triggered resulting in muscle contraction

49
Q

Various factors determine whether a threshold is reached in BER, list three

A

Mechanical - distension of GIT - so like a bolus of food
Nervous
Hormonal

50
Q

The frequency of slow waves is detemined by the inherent rate by what?

A

pacemaker cells establish an inherent rate

51
Q

The frequency of slow waves varies along the

A

GI tract

52
Q

The intensity of contraction by BER once the threshold potential is reached can vary, this is determined by which two factors?

A

The number of action potentials and the cytosolic Ca2+ concentration

53
Q

The enteric nervous system acts on a local scale, what is this therefore referred to as?

A

Intrinsic regulation

54
Q

What nerve is part of the enteric nervous system and runs along the entire length of the GI tract?

A

Intrinsic nerve plexus

55
Q

The enteric system is a sub division of what nervous system?

A

the peripheral nervous system

56
Q

The ENS nerves are embedded in the walls of what?

A

The GI tract

57
Q

On what scale does the enteric nervous system act?

A

On a local scale- coordinates local activity

58
Q

what are the two types of ganglia making up the enteric nervous system

A

the myenteric plexus and the submucosal plexus

59
Q

what is the function of the myenteric plexus

A

responsible for motility

60
Q

what is the function of the submucosal plexus

A

controls secretory activity and blood flow

61
Q

On what scale does the autonomic nervous system act and what is this therefore referred to as?

A

Not on a local scale lol and it is therefore extrinsic

62
Q

What is the autonomic nervous system a part of?

A

The cns

63
Q

What are the two divisions that innervate the smooth muscle of the GI tract?

A

parasympathetic and sympathetic - opposing actions mostly

64
Q

List two neurotransmitters that influence the regulation of digestive function through the autonomic nervous system

A

acetylcholine and noradrenaline

65
Q

Is acetylcholine involved in the parasympathetic or sympatheic nervous system?

A

parasympathetic

66
Q

What does acetylcholine do in the parasympathetic system of the autonomous regulation of the digestive tract

A

It increases motility and increases secretion

67
Q

is noradrenaline involved in the parasympathetic or sympathetic nervous system?

A

sympathetic

68
Q

what does noradrenaline do in the sympathetic system for the regulation of digestive function?

A

It decreases motility and decreases secretion

69
Q

GI hormones have an affect on the regulation of the digestive function, what two things can they do

A

they may have an inhibitory or excitatory effect on the GIT smooth muscle and exocrine gland cells

70
Q

what is the first step in the digestive process?

A

mastication

71
Q

What are the three functions of mastication?

A
  1. break down food into smaller pieces
  2. mix food with saliva
  3. stimulate taste buds
72
Q

one of the functions of mastication is to break down food into smaller pieces for what?

A

to facilitate in swallowing and to increase the surface area for salivary enzymes

73
Q

How many major pairs of salivary glands are there?

A

three homie

74
Q

What are the three major pairs of salivary glands?

A

sublingual, submandibular and parotid

75
Q

what is saliva made of?

A

h20, electrolytes and protein

76
Q

WHat are three important salivary proteins?

A

amylase, mucus and lysosyme

77
Q

*Label the three salivary glands

A

There ya go

78
Q

How does the saliva aid in the breakdown of food?

A

Due to the presence of dietary starches such as amylase

79
Q

How does the saliva facilitate in swallowing

A

because it has mucus

80
Q

Saliva has an antibactrial action, due to what?

A

lysosyme

81
Q

Saliva has bicarbonate buffers, what is this for?

A

to neutralise pH

82
Q

Salivary secretion is continous, roughly what is the average secretion per day

A

1/2 litres

83
Q

What is the basal salivary secretion?

A

it is low level parasympathetic activity which is continous and occurs in the absence of any stimulus

84
Q

Salivary secretion can be reflexly increased from the basal salivary secretion in which two ways

A

simple reflex and conditioned reflex - by the autonomic nervous system

85
Q

what causes the simple reflex for salivary secretion to be activated

A

chemoreceptors and pressure receptors are activated

86
Q

explain how the simple reflex involved in salivary secretion works

A

stimulus - impulses - salivary centre - implulses (extrinsic autonomic nerves) - salivary glands - secretion

87
Q

What is a conditioned reflex

A

a learned response

88
Q

How does a conditioned reflex of the salivary secretion come about

A

salivation occurs without oral stimulation, from thinking/seeing/smelling food

89
Q

what mediates the conditioned reflex of salivary secretion?

A

mediated via cerebral cortex

90
Q

what is special about salivary secretion, the simple and conditioned reflex

A

they are both ONLY under neural control

Biomedical Physiology (19 decks)

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