Brainscape's Knowledge GenomeTM

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


See full index

Pre-Med 2022-2023 > GHM L4 > Flashcards

GHM L4 Flashcards

1
Q

Describe the anatomy of the digestive system

A
  1. Mouth / oral cavity
  2. Tongue
  3. Salivary glands
  4. Pharnyx
  5. Spleen
  6. Stomach
  7. Liver
  8. Kidney
  9. Pancreas
  10. Small Intestine
  11. Large Intestine
  12. Gallbladder
  13. Anus
  14. Oesophagus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

State the functions of the small intestine

A
  1. Completes digestion of food with aid of liver + pancreatic secretions
  2. Absorption of nutrients + minerals into body
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Describe the structure of the small intestine

A

Ileum
Jejunum
Duodenum

Small intestine is long but due to muscle tone, is short in human stomach

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

What is “motility” in the small intestine?

A

Modes of contractions in the small intestine

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

Describe segmentation

A

Mode of contraction found in small intestine, large intestine, predominates in small intestine

Non-adjescent alimentary tract organs contract + relax ALTERNATELY which allows this bidirectional movement of chyme

Bi-directional movement of chyme, for mixing not transport

Increases mixing + absorption

Involunary

Initiated by intrinsic pacemaker cells

Duodenum more active than ileum, slow propulsion

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

Describe peristalsis

A

Mode of contraction found in oesophagus, small intestine, large intestine + rectum

Contraction of circular + longitudinal smooth muscle in coordination to move chyme distally

Adjascent alimentary tract organs contract + relax alternately to move chyme distally along tract

Involuntary

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

Describe the functions of motilin

A

Motilin is released by duodenum + stimulates gastric emptying between meals

This stimulates peristaltic waves successively and distally

This leads to MCC - Migrating Motor Complex which is the “tummy rumble” - removal of indigestable food

MCC originates in stomach + duodenum

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

State the name of the valve between the small intestine and large intestine

A

Ileoceacal valve

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

State two factors which stimulate the opening of the ileoceacal valve

A
  1. Gastroileal REFLEX
  2. Gastrin secretion by parietal cells in stomach

(when terminal end of ileum under pressure)

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

What stimulates the release of motilin in the duodenum?

A

pH / change in pH

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

Describe how the small intestine is innervated

A

Sympathetic nerves:

  1. Splanchnic nerves
  2. Thoracic nerves

Parasympathetic Nerves:

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

Describe how impulses are relayed in the small intestine

A

Impulses are relayed by

  1. Superior mesenteric plexus
  2. Celiac plexus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Describe what happens during parasympathetic excitation

A

Parasympathetic activation - rest & digest

  1. Increase digestive secretions, increase motility, increases salivation
  2. No sympathetic excitation
  3. Dilation of arteries in mesentery
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Which artery supples blood to the small intestine

A

Superior mesenteric artery

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

Which veins drains blood from the small intestine

A

Superior mesenteric vein, which reaches the HEPATIC PORTAL SYSTEM

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

What factors increase blood flow to the intestines?

A
  1. Parasympathetic stimulation
  2. Feeding / taking in food
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What factors constrict blood flow to the intestines?

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

What controls blood flow within the intestines?

A
  1. Glucose
  2. Local hormones
  3. Fatty acids

All REGULATED by ANS

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

State the function of the lesser omentum

A

Lesser omentum - attaches the liver to lesser curvature of stomach

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

What are the mesenteries of the abdominopelvic cavity?

A
  1. Greater omentum
  2. Transverse mesocolon
  3. Sigmoidal mesocolon
  4. Lesser omentum
  5. Mesentery
  6. Parietal peritoneum
  7. Visceral peritoneum
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Describe the anatomy of the duodenum

A

Most short + straight section of small intestine

From pyloric sphincter to duodenal - jejunal junction

Retroperistoneal, static

Most active site of absorption

Connects to liver via lesser omentum

Connects to hepatopancreatic ampulla (bile duct + pancreatic duct)

C-shaped, wraps around pancreas

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

What is coeliac disease?

A

Disease of duodenum

Autoimmune disease

Caused by reaction to gliadin, a gluten protein

Involves tissue transglutaminase

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

State symptoms of coeliac disease

A

Grey, greasy, large stools

Anaemia, fatigue

Vitamin deficiency

Failure to thrive

Lactose intolerance

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

What diseases can coeliac disease get confused with?

A
  1. IBS - irritable bowel syndrome
  2. Wheat allergy
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

When is someone likely to get coeliac disease?

A

Onset infant onwards

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

Describe the structure and function of the ileum and jujenum

A

Specialised for absorption

Intraperitoneal

Suspended in loops from posterior abdominal wall

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

How is the surface area of the small intestine increased?

A
  1. Villi
  2. Circular folds (slow down chyme movement)
28
Q

Describe the anatomy of a villus

A
  1. Absorptive cells
  2. Goblet cell
  3. Lacteal / lymphatic vessel
  4. Blood capillaries
  5. Microvilli
  6. Duodenal glands
  7. Enteroendocrine cells
  8. Intestinal crypt
29
Q

State the function of goblet cells in villi

A

Produce mucus

30
Q

State the function of absorptive cells

A

Enterocytes
Have microvilli

31
Q

Where are goblet cells more commonly found?

A

More numerous in distill end of small intestine

32
Q

Describe the structure and function of intestinal crypts

A

Tubular glands

The epithelial cells of intestinal crypts secrete intestinal juice

33
Q

What stimulates the epithelial cells of the intestinal crypts to secrete intestinal juice?

A

Acidic chyme

34
Q

Where are intestinal crypts more commonly found in small intestine?

A

Proximal end of small intestine (jejunum)

35
Q

Describe intestinal juice and its function

A

pH 7.4 - 7.8
1-2 litres secreted daily
Contains molecular digested food products for absorption
Does not contain enzymes

36
Q

What is the role of enteroendocrine cells?

A

Secrete enterogastrone hormones including
1. CCK (cholecystokinin) (release stimulated by fats + proteins)
2. Secretin - inhibit gastric acid, stimulates release of bicarbonates

Release T cells (intraepithelial lymphocytes), which releaee cytokines when exposed to antigens

37
Q

Describe the location and function of paneth cells

A

Found deep in intestinal crypt

Secrete antimicrobial peptides:
-lysozymes
-defensins

Kill harmful bacteria, allow friendly bacteria to colonise

38
Q

Describe small intestine cell renewal

A

Stem cell daughter cells differentiate into:
-absorptive cells
-enteroendocrine cells
-goblet cells
-paneth cells

Old cells removed by apoptosis

Aftet apoptosis, squammting cells shedd the epithelial layer of villi

Villi epithium replaced every 2-4 days

39
Q

Describe the location of stem cells in the small intestine

A

Deep at the base of intestinal crypt

40
Q

Desribe the location and function of the duodenal glands

A

Found in submucosas of duoednum

Produce alkaline mucos (contains bicarbonate)
to neutralise stomach acid

41
Q

State the cause of a duodenal ulcer

A

Inadequate mucus production from duodenal glands

42
Q

What is the alternative name for the duodenal gland?

A

Brunner’s gland

43
Q

State 3 functions of the large intestine

A
  1. Reabsorption of water from indigested food
  2. Absorption of metabolites from bacteria
  3. Removal of faeces
44
Q

Describe the positioning of the large intestine

A

Wraps around small intestine as three sides of a square

Extends from ileocaecal valve to anus

45
Q

Describe the anatomy of the large intestine

A
  1. Transverse Colon
  2. Ascending colon
  3. Descending colon
  4. Sigmoid colon
  5. Rectum
  6. Anal canal
  7. Vermiform appendix
  8. Cecum
46
Q

Which arteries supply the large intestine with blood?

A

Superior mesenteric artery

Inferior mesenteric artery

47
Q

Which veins drain the large intestine?

A

Inferioir mesenteric vein - splenic vein - superior mesenteric vein - hepatic portal system

48
Q

Name the branches of superior mesenteric artery

A

RIIM

Right colic artery
Intestinal artery
Ileocolic artery
Middle colic artery

49
Q

Name the branches of the inferior mesenteric artery

A

RS

Left colic artery
Superior rectal artery
Sigmoidal arteries

50
Q

What is the function of the rectum?

A

Temporary storage of faeces

51
Q

Describe why a patient may suffer from constipation

A

Defecation does not happen / delayed

Faeces returned to colon

More water absorption occurs

52
Q

State the function of the rectal valve

A

Prevent faeces moving with flatus

53
Q

Why may a patient suffer from haemarrhoids

A

Haemarrhoid veins inflammed

54
Q

State the function of anul sinuses

A

Release mucus when compressed

55
Q

Describe the anatomy of the rectum and anal canal

A

Rectal valve

Haemarrhoidal veins

Pectinate line

Anal sinuses

56
Q

Which nerve fibres surround the pectinate line

A

Visceral sensory fibres - ANS

Somatic sensory fibres

57
Q

Describe the mucosa of large intestine

A

Thick mucosa, lots of intestinal crypts, goblet cells

Colon + Rectum made of simple columnar epithelium

Anal canal - 3 types of epithelium:

Simple columnar epithelium
Stratified squammous epithelium
Stratified squamomous keratanised epithelium

No enzymatic secreting cells, no villi, no circular folds

58
Q

What are “flora” of the large intestine

A

Symbiotic Bacteria

59
Q

Describe symbiotic functions of bacteria in large intestine

A

Synthesis of vitmains B and K

Metabolises certain secretions - mucin

Ferments carbs (cellulose) producing flatus

60
Q

List the contents of faeces

A
  1. Undigestable food
  2. Water
  3. Mucus
  4. Bacteria
61
Q

Why is faeces brown?

A

Contains stercobilin - bile pigement
Produced as a product of haemoglobin breakdown
Without, faeces would be pale white

62
Q

State the 2 types of motilities which occur in the large intestines

A

Mode of contractions

  1. Mass movement / contractions
  2. Pocket / haustral contractions
63
Q

Describe mass movement in the large intestine

A

Slow, long distace

Involves large regions of the colon

Peristalsis

Dietry fibre aids this type of motility

64
Q

Describe haustall contraction in the large intestine

A

“pocket movement”

Involves only one haustum

Slow, short distance

Segmentation, mixing of food, aids water reabsorption

Propelling food from one haustum to the next

65
Q

Exactly where in the large intestine does haustal contraction take place

A

Ascending, transverse colon

66
Q

When does mass movement / contraction take place in large intestine

A

After eating meal - this leads to gastroileal reflex which causes the motility

67
Q

When does haustral contraction take place in large intestine

A

as a reaction to distension

Pre-Med 2022-2023 (57 decks)

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