Brainscape's Knowledge GenomeTM

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


See full index

Bioscience 2 > Digestive System 2 > Flashcards

Digestive System 2 Flashcards

1
Q

5 Functions of the gut

A
  • Motility
  • Secretion
  • Digestion
  • Absorption
  • Storage
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the 2 types of gut control?

A

Intrinsic control and extrinsic control

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

What is intrinsic control?

A

Where the gut controls itself

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

What is extrinsic control?

A

Where the gut is controlled by an external factor outside the gut.

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

What are the 2 types of control that intrinsic control can have?

A

Neuronal = enteric nervous system

Hormonal = secretin, gastrin, CCK, GIP, Motilin

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

What are the 2 types of control that extrinsic control can have?

A

Neuronal = Vagus and Splanchnic Nerves

Hormonal = Aldosterone

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

Name the 4 parts of the gastrointestinal tract

A
  • Mucosa
  • Submucosa
  • Tunica muscularis
  • Serosa / adventitia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How is gut regulation controlled in the enteric nervous system? What are the 3 inputs?

A

By input from the:

  • luminal receptors
  • hormones
  • autonomic nervous system
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the function of the myenteric plexus?
What control is it under?

A

Regulates motility and muscle action

Under control of the Parasympathetic nervous system

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

What is the function of the submucosal plexus?
What control is it under?

A

Regulates local fluid and hormone release

Under control of the parasympathetic nervous system only

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

What are the 3 main types of luminal receptors?

A

Mechanoreceptors

Chemoreceptors

Osmoreceptors

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

What do mechanoreceptors do?

A

Detect stretch and stimulate contractions

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

What do chemoreceptors do?

A

Sense chemical composition of the chyme and regulate pH

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

What do osmoreceptors do?

A

Sense osmolarity and control motility and secretions

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

What are the 2 functional divisions of the autonomic nervous system?

A

Sympathetic nervous system - fight or flight

Parasympathetic nervous system - rest and digest

Two neurone pathways

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

Key anatomical features of the sympathetic nervous system:

A
  • Originate at T1 - L2
  • Enter the sympathetic chain
  • Leave the sympathetic chain
  • Synapse at prevertebral ganglia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Key functions of the sympathetic nervous system:

A
  • slow digestive transit
  • closes sphincters
  • Fight or flight
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Key anatomical features of the parasympathetic nervous system:

A
  • Originate at brainstem or S-levels
  • Travel to target organ - along vagus nerve
  • Synapse at target
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Key functions of the parasympathetic nervous system:

A
  • Increases digestion
  • Opens sphincters
  • Rest and digest
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How is gut regulation controlled by the autonomic nervous system?

A

The sympathetic nervous system:
- decreases digestive secretions
- decreases digestive motility

The parasympathetic nervous system:
- Increases rest and digest
- Increases digestive motility

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

what does the suffix -crine mean?

A

= secrete

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

What does endocrine mean?

A

= secreted into blood

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

What does neurocrine mean?

A

Secreted by nerves

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

What does paracrine mean?

A

Secreted by adjacent cells

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

What does autocrine mean?

A

Secreted by self

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

What is the structure of a gut endocrine cell?

A
  • Columnar
  • Narrow apex - sensory - exposed to gut lumen
  • Wide base - secretory
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What are the 3 phases of digestion?

A
  • Cephalic
  • Gastric
  • Intestinal
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What is the cephalic phase?

A

= in the head - Salivation

  • Stimulated by parasympathetic innervation (Cranial nerves)
  • Increases blood flow to glands
  • Brainstem regulates visual or olfactory (response to sense of smell) salivation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What is the gastric phase?

A

= in stomach

  • Acid production and enzyme secretion
  • Sphincter relaxed
  • Relaxation of stomach and duodenum - allowing entry of chyme
  • Parasympathetic stimulation
  • Gastrin - produced by cells in duodenum, stomach and pancreas
  • Secretin produced
  • Cholecystokinin produced
  • Motilin produced
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What is the function of Gastrin?

A
  • Increases acid secretion
  • Increases pepsinogen secretion
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What is the function of Secretin?

A
  • stimulates bile secretion
  • Prevents acid secretion
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What is the function of cholecystokinin?

A
  • Stimulates bile and pancreatic secretion
  • Also affects motility
  • Decreases gastric emptying
33
Q

What is the function of motilin?

A
  • Increases motility/peristalsis in the gut
  • Clears tract between meals
34
Q

What is hunger and satiety controlled by?

A

=Hypothalamus

–> regulates the basic biological drives related to survival

the 4Fs = Fighting, Fleeing, Feeding, ‘mating’

35
Q

What are the 2 parts of the hypothalamus that control hunger and satiety?

A

Ventro medial area = Inhibitory - Satiety centre

Lateral Area = Facilitative - Appetite Centre

36
Q

What is the name of the hunger hormone? What is its function?

A

= Ghrelin

= stimulates hunger

37
Q

How is ghrelin stimulated?

A

Stimulated by an empty stomach / fasting

Low blood glucose - Sensory input
= appetite stimulated

38
Q

Where is ghrelin released?

A

Released by pancreas and stomach

39
Q

What is the satiety hormone? What is its function?

A

= Leptin

  • Opposes the action of ghrelin - indicates fullness (satiety)
40
Q

What is leptin produced by?

A

Produced by fat cells (adipocytes)

41
Q

How does leptin act on its target?

A

Crosses the blood brain barrier to reach the hypothalamus

42
Q

What can occur if leptin stops working?

A

= severe over eating and obesity

43
Q

What are 3 other satiety hormones?

A
  • Cholecystokinin
  • Peptide YY
  • Glucagon - like peptide 1

–> all released in response to food. Neural controls carried by Vagus nerve but may be reliant on hormones.

44
Q

What is the endocrine section of the pancreas?

A

The islets of Langerhans

45
Q

What is located in the islets of Langerhans?

A

Alpha -cells
Beta -cells
D-cells

46
Q

What do alpha cells secrete?

A

= Glucagon

47
Q

What do Beta cells secrete?

A

Insulin

48
Q

What do D cells secrete?

A

= Somatostatin

–> present throughout pancreas but most abundant in the tail.

49
Q

When is glucagon secreted?

A

Secreted when blood glucose level falls.

Triggers breakdown of glycogen into glucose in the liver

50
Q

When is insulin secreted?

A

Secreted when blood glucose is high.
Triggers storage of glucose in liver, skeletal muscle and fat cells.

51
Q

When is somatostatin secreted from D cells?

A

Secreted induced by low pH.
Supresses the release of hormones from Alpha and Beta cells.
Inhibits gut motility and exocrine secretion.

52
Q

What is the definition of obesity?

A

Abnormal or excessive fat accumulation that presents a risk to health.

  • A BMI over 25 is overweight.
  • Over 30 is obese.
53
Q

How do you calculate BMI? What are the units of BMI?

A

= body mass / (height)^2

Units = kg/m^2

54
Q

What are the categories for BMI

A

<18.5 Underweight
18.5 – 24.9 Ideal
25 - 29.9 Overweight
>30 Obese

55
Q

What are alternatives to BMI?

A
  • Waist circumference
  • Waist to hip ratio
  • Skinfold thickness
  • Bioelectrical impedance
  • MRI or DEXA
56
Q

What are some examples of health risks of obesity?

A

Risks of metabolic, cardiovascular and musculoskeletal disorders and cancers.

Diabetes
Gallbladder disease
Sleep apnea
Cardiovascular disease
Osteoarthritis
Colon cancer
Gout

57
Q

What are some environmental factors influencing obesity?

A

Cost of food
Portion size
Type of food
Physical activity
Total energy intake

58
Q

How can obesity be managed?

A

Physical activity
Dietary strategies
Medication
Surgery

59
Q

What are more invasive methods of reducing obesity?

A

= Bariatric Surgery
- restrictive - reduced stomach size and dietary intake
- malabsorption (bypasses stomach and small intestine)

=Gastric band (restrictive, minimally invasive, adjustable)

=Gastric bypass ( malabsorptive / restrictive, invasive, irreversible)

= Gastric sleeve ( restrictive, invasive, irreversible)

60
Q

What is saliva?

A

a product of a number of glands present within and around the oral cavity

61
Q

What are major salivary glands?

A

paired and exist away from the oral cavity, draining into the cavity via a long duct –> exocrine glands

62
Q

What are minor salivary glands?

A

present throughout the mucosa of the oral cavity

63
Q

What supplies salivary glands?

A

innervated by parasympathetic neurones carried in a number of cranial nerves

64
Q

What are the 3 main salivary glands?

A

Parotid gland
Submandibular gland
Sublingual gland

65
Q

What type of secretion does the parotid gland have?

A

Serous secretion

66
Q

What type of secretion does the submandibular gland have?

A

Mixed secretion ( serous and mucous secretion)

67
Q

What type of secretion does the sublingual gland have?

A

Mainly mucous secretion

68
Q

What is the location and function of the parotid gland?

A

Sits beside the ear
Drains into the vestibule via the parotid duct
Largest of the paired salivary glands

69
Q

What is the location and function of the submandibular gland?

A

Sits under the jaw (mandible)
Drains into the floor of the mouth, under tongue.

70
Q

What is the location and function of the sublingual gland?

A

Present beneath the tongue.
Drains directly into the oral cavity via a number of small ducts.
Paired gland.

71
Q

What are the 8 main functions of saliva?

A

Digestion
Mineralisation
Antimicrobial
Buffering
Lubrication
Agglutination
Gustation
Hydration

72
Q

What are the functions of saliva in: Digestion

A

digestive enzymes present in saliva - amylase, mucins, lipases

73
Q

What are the functions of saliva in: Mineralisation

A

Proteins within saliva produce protective layer - assists in mineralisation of teeth

74
Q

What are the functions of saliva in: Antimicrobial

A

Saliva compounds can kill bacteria e.g amylase, mucins

75
Q

What are the functions of saliva in: Buffering

A

a delicate pH balance is needed for digestion and to protect the teeth. Carbonic anhydrase is buffer present in saliva

76
Q

What are the functions of saliva in: Lubrication

A

Saliva coats mucosa of the oral cavity

77
Q

What are the functions of saliva in: Agglutination

A

Bacteria present in the oral cavity is trapped in saliva

78
Q

What are the functions of saliva in: Gustation

A

(tasting) made possible by saliva, detection from taste buds when food is dissolved in saliva

79
Q

What are the functions of saliva in: Hydration

A

receptors can detect hydration levels and stimulate desire to drink

Bioscience 2 (21 decks)

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