Brainscape's Knowledge GenomeTM

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


See full index

Physiology Essentials > Digestive System > Flashcards

Digestive System Flashcards

1
Q

What are the digestive organs?

A

-Mouth
-Pharynx
-Oesophagus
-Stomach
-Small intestine
-Large intestine
(part of digestive tract: 4 layer tissue structure)

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

What are the accessory organs?

A

-Teeth
-Tongue
-Salivary glands
-Liver
-Gallbladder
-Pancreas
(provide digestive assistance, no 4 layer tissue structure)

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

What are the 4 layers of the digestive tract?

A

Mucosa
Submucosa
Muscularis Externa
Serosa

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

Describe what, where and function of mucosa

A

What is it?
-Mucous membrane
-Consisting of digestive epithelium: (simple columnar cells, enteroendocrine, mucous cells and goblet cells), lamina propria: alveolar tissue with blood vessels, sensory nerve endings, lymphatic vessels, tissues & muscular mucosa: smooth muscle
Where is it?
-Closest to lumen
Function
-Secretion & absorption
-Protection against digestive acids and enzymes
-Contraction of smooth muscle alters shape of lumen

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

Describe what, where and function of submucosa

A 
What is it?
-Layer of dense irregular connective tissue that contains large blood vessels, lymphatic vessels and exocrine glands
Where is it?
-2nd closest to lumen
Function
-Secretes buffers and enzymes into lumen
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Describe what, where and function of muscularis externa

A

What is it?
-2 layers of smooth muscle innervated by enteric nervous system
Where is it?
-Furthest from lumen
Function
-Enables attachment to adjacent structures

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

Describe what, where and function of serosa

A 
What is it?
-Serous membrane
Where is it?
-Furthest from lumen
Function
-Enables attachment to adjacent structures
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the functions of the digestive system?

A
  1. Ingestion
  2. Mechanical processing
  3. Digestion
  4. Secretion
  5. Absorption
  6. Excretion
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Describe ingestion in the digestive system?

A

Material enters digestive tract via mouth

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

Describe mechanical processing in the digestive system

A
  • Easier to propel along tract

- Increases surface area to allow easier breakdown

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

Describe digestion in the digestive system

A
  • Chemical breakdown of food for absorption
  • Large molecules (e.g. carbohydrates/starches) broken down to small molecules
    (e. g. absorbable sugars)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Describe secretion in the digestive system

A

Release of water, acids, enzymes, buffers, salts

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

Describe absorption in the digestive system

A

Movement of substrates, electrolytes, vitamins and water across walls of
digestive epithelium into interstitial spaces in lamina propria

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

Describe excretion in the digestive system

A

Removal of waste products from body

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

What are the two processes by which materials move through the digestive tract?

A

Peristalsis and Segmentation

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

What is peristalsis?

A

A propulsion process involving waves of smooth muscle contraction that move compacted ingested materials (bolus) along digestive tract

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

What is segmentation

A

Cycles of smooth muscle contraction and relaxation that chums and fragments the bolus to mix the contents of the bolus with secretions (eg: enzymes)

18
Q

What are functions of the mouth/oral cavity

A
  1. Sensory analysis of material before swallowing
  2. Mechanical processing (chewing)
  3. Lubrication
    - Digestion begins here
    - Salivary amylase breaks down starch
    - Lingual amylase breaks down lipids
    - Salivary glands produce saliva
19
Q

What is function of saliva?

A 
-Lubrication of mouth/ pharynx
• Cleanse mouth/teeth
• Moistening food
• Dissolve food/chemicals
• Begin digestion
20
Q

What is the structure of the stomach?

A 
-3 layers of smooth
muscle
-Rugae
-Storage, mixing
chamber
21
Q

What is the function of the stomach?

A 
Mechanical digestion
-Forms chyme, forced into duodenum
Chemical Digestion
-Denatures proteins (HCI)
-Coverts pepsinogen to pepsin
22
Q

What are the 3 phases of regulation of gastric activity?

A

Cephalic Phase
Gastric Phase
Intestinal Phase

23
Q

Describe Cephalic Phase

A

-Begins: sight, smell, taste, though of food
(leads to)
-Action potentials in vagus nerve
(stimulates)
-High secretion of gastrin (G cells), mucous (mucous cells), HCL (parietal cells) and pepsinogen (chief cells)
-Prepares stomach for arrival of food

24
Q

Describe Gastric Phase

A 
-Begins: arrival of food in stomach
(stimulates)
-Stretch receptors and chemoreceptors
(stimulates)
-High secretion of gastrin (G cells), mucous (mucous cells), HCL (parietal cells) and pepsinogen (chief cells)
-High gastric activity
25
Q

Describe Intestinal Phase

A

-Begins: chyme enters duodenum
(stimulates)
-High secretion of (in duodenum) secretin, cholecystokinin (CCK) and gastric inhibitory peptide (GIP)
-Control rate of gastric emptying (from stomach to duodenum)

26
Q

What is the function of the duodenum?

A

-Receives chyme from stomach
-Mixes with digestive enzymes from
pancreas
-Neutralises acid

27
Q

What is the function of the jejunum?

A

Chemical digestion & nutrient absorption

28
Q

What is the function of the Ileum?

A

Nutrient absorption

29
Q

What are the features of the small intestine that maximise surface area?

A
  • Length (approx. 6m)
  • Large surface area
  • Circular folds (plicae circulares)
  • Villi: contain capillaries and lacteals
  • Microvilli: have a brush border
30
Q

What are the 3 parts of the small intestine?

A

1) Duodenum
2) Jejunum
3) Ileum

31
Q

How does the pancreas contribute to digestion?

A

Controlled by duodenal hormones (CCK and

secretin) , Pancreatic secretions:
- Water
- Salts
- Bicarbonate & phosphate buffers (release stimulated by Secretin)
- Enzymes to digest nutrients (release stimulated by CCK)

32
Q

What are the main functions of the liver?

A
  1. Metabolic regulation
    - Carbohydrate, lipid & protein metabolism
    - Waste removal
    - Store vitamins/minerals
  2. Haematological regulation
    - Removal of bacteria, old RBC/WBC
    - Make plasma proteins
    - Removes hormones/antibodies
    - Removes/stores toxins
    - Activates vitamin D
  3. Bile production
33
Q

What is the role of bile in the digestive system?

A
  • Bile produced in liver; stored in gall bladder
  • Digests lipids
  • Bile salts break droplets apart (emulsification)
34
Q

Describe the main steps involved in the digestion and absorption of carbohydrates

A 
ORAL CAVITY 
(salivary amylase)
SMALL INTESTINE
-Brush border enzymes breaks down disaccharide lactose to glucose
(absorption)
CAPILLARIES
35
Q

Describe the main steps involved in the digestion and absorption of lipids?

A 
ORAL CAVITY
(lingual lipase)
SMALL INTESTINE
-Bile salts- allows access to enzymes, pancreatic lipase
(absorption)
LACTEALS
36
Q

Describe the main steps involved in the digestion and absorption of proteins?

A 
ORAL CAVITY
(chewing-access to enzymes)
STOMACH
(pepsinogen --> pepsin)
SMALL INTESTINE
-Brush border & pancreatic enzymes
(absorption)
CAPILLARIES
37
Q

How does the large intestine histological structure differ from the small intestine?

A
  • No villi or circular folds in mucosa: haustra instead

- Muscularis externa different to SI

38
Q

What are the two key functions of the large intestine?

A
  • Reabsorption of water

- Compaction of intestinal contents into feces

39
Q

Describe chemical digestion in large intestine

A 
-Final stage of digestion occurs through
activity of bacteria
-Produces gases and other by-products
-Bacteria produce enzymes that humans
don’t have genetic capacity to produce
40
Q

Describe mechanical digestion in the small intestine

A
  • Movement of LI begins when substances pass ileo-caecal sphincter
  • Peristalsis slower waves than SI
  • Haustral churning (segmentation)
  • Mass movements

Physiology Essentials (13 decks)

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