Brainscape's Knowledge GenomeTM

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


See full index

Anatomy MD2001 > GI System > Flashcards

GI System Flashcards

1
Q

What is the mucosa layer of the GI made up of?

A

epithelium
lamina propria
muscularis mucosa

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

Properties of epithelium in GI?

A

continuous lining in GI tract
shed and replaced every 2-3 days
apical side faces GI lumen, basolateral side faces interstitium and vasculature
extent of vili and crypts depend on the section function of GI

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

What is the lamina propria?

A

Loose connective tissue made up of elastic and collagen fibres
contains sensory nerves, lymph vessels and secretory glands

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

What is the muscularis mucosa?

A

thin layer of smooth muscle that increases surface area by creating ridges and folds

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

What is the submucosa?

A

Thicker layer with similar composition to lamina propria
incorporates blood vessels and nerve bundles that form a submucosal plexus- it is an integral part of enteric nervous system

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

What is the Meissner Plexus?

A

Submucosal plexus

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

What is the muscularis externa made up of?

A

circular muscle
myenteric plexus
longitudinal muscle

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

What is the Auerbach plexus?

A

Myenteric plexus

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

Properties of muscularis externa

A

ENS coordinates contractions to mix and move contents between compartments, sphincters regulate this flow.

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

What makes up the serosa?

A

Outermost layer of connective tissue and squamous epithelial cells

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

What do sections of the GI tract have if they do not have a serosal layer?

A

They connect directly with adventitia

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

What divisions of the autonomic nervous system regulate the GI?

A

parasympathetic
sympathetic
enteric

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

Where is GI innervation from the parasympathetic nervous system derived from?

A

Vagus in the medulla oblongata

Pelvic splanchnic nerves in S2-S4

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

What stimulates the sensory and motor components of the parasympathetic NS?

A

stretch
pressure
temperature
osmolarity

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

What are the primary transmitters of the parasympathetic NS in the GI?

A

acetylcholine ACh
gastric-releasing peptide
substance P

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

What processes does the parasympathetic nervous system facilitate in GI system? *

A

digestion and absorption of nutrients

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

Where does the nerves of the sympathetic nervous system originate and synapse?

A 
Originate:
thoracic region T5-T12
lumbar region  L1-L3
celiac ganglion
Synapse:
superior mesenteric ganglion
inferior mesenteric ganglion
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What innverates the upper GI region? (sympathetic NS)

A

Nerves that synapse in superior cervical ganglion

decreases GI secretions and motility

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

Organisation of ENS nerves?

A

myenteric and submucosal plexuses

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

Operation of ENS?

A

Autonomously by intrinsic regulation and sensory reflexes

21
Q

Properties of myenteric plexus?

A

dense parallel neuronal configuration
regulates intestinal smooth muscle
tonic and rhythmic contractions

22
Q

Properties of submucosal plexus?

A

regulates intestinal secretion and local absorptive environment
can synapse on blood vessels, circular muscle and longitudinal muscle, and muscularis mucosa

23
Q

What supports ENS neurons?

A

enteric glial cells that resemble brain astrocytes

24
Q

What regulates ENS reflexes?

A

Neural circuits involving mechanoreceptor or chemoreceptor stimulation in mucosa

25
Q

Explain how a signal is transmitted in ENS?

A

Signal transmitted to neurons in submucosal plexus, which stimulate other neurons in submucosal or myenteric plexus that regulate endocrine or secretory cells

26
Q

What neurotransmitters are used by ENS?

A

enkephalins: constrict circular muscle around sphincters

VIP, substance P, ACh, nitric oxide and seratonin

27
Q

Explain cephalic phase of digestion*

A

triggered by the thought of food

Neural and causes release of ACh and VIP which stimulates secretion by salivary glands, stomach, pancreas, intestines

28
Q

Explain the gastric phase of digestion*

A

begins when food or oral secretions enter stomach
coincides with distension
neural, hormonal and paracrine GI responses

29
Q

Explain intestinal phase of digestion*

A

begins when stomach contents reaches duodenum

hormone, paracrine and neural responses

30
Q

GI hormones

A 
cholecystokinin
gastrin
glucose dependent insulinotropic peptide
motilin
sectretin
31
Q

GI paracrines

A

histamine (increases secretion)
somatostatin (decrease secretion)
prostagladins (decrease secretion)

32
Q

What is the role of the upper GI tract?

A

transports and prepares food for absorption- breaking food down and hydrating to improve environment for enzymatic action

33
Q

Role of mouth*

A

mechanical and chemical breakdown with mastication (chewing)

34
Q

Role of salivary glands

A

Produces saliva by sublingual and submandibular and parotid glands
lubricates mouth, begins food digestion and is protective

35
Q

What type of process is swallowing?*

A

A parasympathetic process

provides afferent feedback to swallowing centre and efferent responses through other nuclei

36
Q

Describe the process of swallowing*

A

tongue forces food back to initiate voluntary process
soft palate pulled upward to close access to nasopharynx
larynx and hyoid bone pulled upwards and epiglottis closes off access to larynx
upper esophageal sphincter relaxes to allow food to enter esophagus

37
Q

What is peristalsis? *

A

A series of coordinated muscle contractions/relaxations that commence after the upper esophageal sphincter and propels food down oesophagus

38
Q

What are the functions of the stomach?

A

accept and store food
mix food with secretions
digest food
deliver food to small intestine

39
Q

How are salivary secretions controlled?

A

by sympathetic and parasympathetic processes in 2 steps

  1. Na+ and Cl- transported into duct lumen
  2. ductal cells modify them by reabsorbing Na+ and Cl- and secreting HCO3 and K+
40
Q

Gastric secretions

A 
ions
water
mucus from mucus neck cells
pepsinogen from chief cells
intrinsic factor and H+ from paritetal cells
41
Q

Properties of small intestine *

A

longest section where most macronutrient, vitamin and mineral absorption occurs
mixing by segmentation and propulsion by peristalsis of contents
made up of duodenum, then jejunum, then ileum (longest)

42
Q

Properties of large intestine *

A

consist of caecum, ascending, transverse and descending, sigmoid colon, rectum and anus
where water and ion absorption take place
segmentation, peristalsis and mass movement occur

43
Q

What does the ileocecal sphincter do?

A

regulates amount of chyme entering large intestine

44
Q

Function of sympathetic nervous system in relation to GI system? *

A

Sympathetic stimulation causes inhibition of gastrointestinal secretion and motor activity, and contraction of gastrointestinal sphincters and blood vessels.

45
Q

Function of enteric nervous system in relation to GI system? *

A

It contains full reflex circuits for control of intestinal motility, fluid transport, blood flow and nutrient handling.

46
Q

Role of oesophagus? *

A

Transports food from mouth to stomach

47
Q

What are the different parts of the stomach from top to bottom?

A

Fundus
Body
Antrum
Pyloric sphincter

48
Q

What are the layers of the GI from inside to out?

A

Mucosa
Submucosa
Muscularis externa
Serosa

Anatomy MD2001 (21 decks)

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