Brainscape's Knowledge GenomeTM

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


See full index

Anatomy > Digestive System > Flashcards

Digestive System Flashcards

1
Q

What is the primary function of digestive system?

A

Primary Function of Digestive System
* To break down food and/or liquids into smaller units of absorbable nutrients which are used by your body to generate energy

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

On average how
long do you think it takes for the sandwich you ate at lunch to
completely pass through your digestive tract?

A

24 hours

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

What is the Alimentary canal?

A

Alimentary canal
* Structures form long tube that breaks down food
* It takes approximately 24 hours from ingestion to defecation

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

What are the Accessory digestive organs?

A

Accessory digestive organs
* Participate in digestive process but food does not pass through
these structures
* Examples:
- Liver
- Pancreas
- Gallbladder
- Salivary glands

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

What is Ingestion?

A

Ingestion
* Put food into mouth

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

What is Propulsion?

A

Propulsion
* Movement of food through canal
* Swallowing is voluntary
* Peristalsis is involuntary

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

What is Mechanical digestion

A

Mechanical digestion
* Physical breakdown of food particles
* Chewing, churning, segmentation

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

What is Peristalsis?

A

Peristalsis
* An organized contraction and relaxation of smooth muscle layers that propels food through the alimentary canal in one direction
- Ex. cookie dough gets squeezed out
- Allows you to eat upside down

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

What is Segmentation?

A

Segmentation
* Contractions of smooth muscle move chyme (food product being digested) back and forth within canal to allow mixing and further breakdown
- mix up food particles and digestive enzymes
- homogenous mixture of food and enzymes

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

What is Chemical digestion?

A

Chemical digestion
* Enzymes and chemicals break down food

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

What is Absorption?

A

Absorption
* Particles (ex. Sugars, fatty acids, etc.) are
transported from canal into blood and lymph
capillaries

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

What is Defecation?

A

Defecation
* Indigestible products are eliminated as feces

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

What are the layers of the Alimentary Canal

A
  • The inner canal = lumen
  • There is a consistent layering of tissues that form most of
    the alimentary canal (there are some exceptions to be noted later)
  • From lumen to outer layer:
    • Mucosa: lines lumen
    • Submucosa: support layer
    • Muscularis externa: muscle layer
    • Serosa: outer surface
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the 3 sublayers of Mucosa?

A

3 sublayers:
1. Epithelium
* Type varies by location
* Mucus production, absorption, protection, etc.
* Continuous & contains many digestive glands
2. Lamina propria (loose areolar)
* Capillary rich (absorption)
* MALT = mucosa associated lymphoid tissue
* Provides defense
3. Muscularis mucosa (thin layer smooth
muscle)
* Localized movements, helps glands expel
contents

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

What are the components of submucosa?

A

Submucosa
* Similar to loose areolar CT but more collagen fibers (provide support)
* Highly vascularized
- Nutrient absorption
* Glands connecting to lumen may project to submucosa
* Submucosal nerve plexus
- Control of muscle cells, glandular secretions, etc. (more on this later…)

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

What are the components of Muscularis Externa?

A

Muscularis Externa
* 2 layers smooth muscle (stomach has 3)
* Circular: inner layer, typically squeezes tube
* Longitudinal: outer layer, typically shortens tube
* Peristalsis and segmentation
* Myenteric nerve plexus
* Innervates muscularis externa and is between longitudinal and circular muscles (more on this later…)

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

What is the enteric nervous system?

A
  • The enteric nervous system controls smooth muscle and
    glands of alimentary canal
  • Considered the “brain in the gut” - - Has as many neurons as the entire spinal cord
  • Reflex arc exists (sensory neurons –> interneurons –> motor neurons)
  • Made of two nerve plexuses within the wall of alimentary canal
    • Submucosal nerve plexus
    • Myenteric nerve plexus
  • Is influenced by the autonomic nervous system
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the components of Serosa?

A

Serosa
* Found around organs within abdominal cavity
* Simple squamous epithelium + a thin loose areolar CT = Serous membrane

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

What is esophagus lined with?

A
  • The esophagus is lined with adventitia (a fibrous CT)
  • The esophagus is not contained
    within a body cavity lined with a
    serous membrane
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is Enteric Nervous System?

A

Enteric Nervous System
* Is located entirely within the wall of the alimentary canal
* Nerve plexuses allow for a localized response within visceral organs
* Partly independent of central nervous system
* Myenteric nerve plexus
* Submucosal nerve plexus

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

What is the Myenteric nerve plexus?

A

Myenteric nerve plexus
* Controls peristalsis and segmentation
* Within muscularis externa

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

What is the Submucosal nerve plexus?

A

Submucosal nerve plexus
* Controls secretions of glands & muscularis mucosa contractions
* Within submucosa

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

What is the Submucosal nerve plexus?

A

Submucosal nerve plexus
* Controls secretions of glands & muscularis mucosa contractions
* Within submucosa

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

What is the oral cavity?

A

Oral Cavity
* Mouth
* Ingestion of food
* Mechanical digestion
- Chewing = mastication
* Chemical digestion
- Mixed with saliva that contains amylase
– Starts chemical breakdown of carbohydrates

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

What is the Anatomy of the Mouth?

A

Mouth Anatomy
* Stratified squamous epithelium
* Thin submucosa layer anchored directly to underlying bone
* No muscularis externa or serosa/adventitia
* Lips

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

What is the Anatomy of the Lips?

A

Lips: margin between skin and oral cavity (lip proper = transition part)
* Poorly keratinized, translucent
- Red color from underlying capillaries
* No eccrine or sebaceous glands
* Lower lip 12X more likely to get nonmelanoma skin cancer

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

What is the Anatomy of the tongue?

A

Tongue
* Accessory digestive organ
* Superior surface (the part you see when you say “ah”) iscovered in keratinized stratified squamous epithelium
- Keratin makes it look whitish
* Moves food, helps mix to form bolus
(also involved with speech)
* Filiform papillae
- Rough surface
* Fungiform and circumvallate papillae
- Contain taste buds

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

What is the Lingual Frenulum?

A

Lingual Frenulum
* Lingual frenulum
* Fold of mucosa layer
* Connects tongue to floor of mouth

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

What is being “Tongue Tied”

A

Tongue Tie”
* If lingual frenulum extends too far forward, the tip of the tongue cannot move and speech is difficult
* Called ankyloglossia
* Makes saying sounds where the tongue touches teeth (letters such as t, z, p)
* Can be corrected surgically

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

What are the components salivary glands?

A

Salivary Glands
* Accessory digestive organs
* Exocrine glands
* Produce saliva

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

What are the components of salvia?

A

Saliva
* Moistens mouth
* Dissolves food (so can taste)
* Contains digestive enzymes
- Amylase starts breakdown of carbohydrates
- Lipase begins digestion of fats
* Contains mucus (helps swallowing)
* Neutralizes acids produced by bacteria that promote decay (has bicarbonate buffer)
* Antibacterial and antiviral components

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

What are the cell types of the Salivary Glands?

A

Cell types
* Serous cells secrete digestive enzymes
* Mucous cells secret mucus

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

What are the primary salivary glands?

A
  • Parotid gland and duct
  • Submandibular gland and duct
  • Sublingual gland and ducts
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What are the components of Parotid glands and ducts?

A

Parotid gland and duct
* Largest salivary gland
* Contains serous cells
- Produce watery enzyme-rich secretion
* Empties near 2nd upper molar

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

What is Mumps?

A

Mumps
* Viral infection
- Parotid glands swell; painful

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

What are the components of Submandibular gland and ducts?

A

Submandibular gland and duct
* Approximately equal amounts of serous and mucous cells
* Ducts open lateral to lingual frenulum

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

What are the components of Sublingual gland and ducts?

A

Sublingual gland and ducts
* Mostly mucous cells (secrete
mucus)
* Several ducts empty below
tongue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

What are the components of teeth?

A

Teeth
* Accessory digestive organs
* Involved in mastication (= chewing)
* Heterodont dentition
* Different shapes of teeth for different jobs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

What are Deciduous teeth?

A

Deciduous teeth
* “Baby teeth”
* 20 total erupt typically between ages 6 months
to 6 years

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

What are Permanent teeth?

A

Permanent teeth
* 32 total that gradually replace deciduous
* “Wisdom teeth” = 3rd molars
* Emerge between 17 and 25 years old (not always 
can become impacted and do not emerge, or are
sometimes missing)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

What are the regions of a tooth?

A

Regions of a Tooth
* Crown
- Part above gum line
* Neck
- Narrow, contained within gum tissue
* Root
- Contained within bone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

What is the anatomy of teeth?

A
  • Pulp
  • Dentin
  • Enamel
  • Cement
  • Periodontal ligament
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

What is the pulp of a tooth?

A

Pulp
* Loose areolar CT with blood vessels and
nerves
* Provides nutrients and sensation to tooth
* Odontoblasts create dentin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

What is the Dentin of a tooth?

A

Dentin
* Collagen (from odontoblasts) and
minerals
* Forms bulk of tooth; deep to enamel
* Has radial striations = dentinal tubules
* Can contribute to tooth sensitivity
* No cells or blood vessels
* Harder than bone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

What is the Enamel of a tooth?

A

Enamel
* Hardest substance in body
* 99% calcium salts
(hydroxyapatite crystals)
* No cells or blood vessels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

What is the cement of a tooth?

A

Cement
* Calcified CT that covers root

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

What is the Periodontal ligament of a tooth?

A

Periodontal ligament
* Dense CT that attaches cement
of tooth to bony socket

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

What is a cavity?

A

Demineralization of enamel and dentin
* Begins with dental plaque
* Biofilm of sugar, bacteria and other
debris on teeth
* Bacteria break down sugars and produce
acids
* Dissolve calcium salts of teeth
(demineralization of enamel)
* Bacteria also produce protein-digesting
enzymes that destroy organic component
of teeth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

What is the Root Canal Procedure?

A
  • A root canal may be required when the pulp within the canal
    becomes infected
  • Pulp is drilled out
  • Tooth is now “dead”
  • Cavity is sterilized and filled
  • Tooth is capped off to help strengthen it
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

What is the Pharynx?

A
  • Pharynx connects oral cavity to
    esophagus and nasal cavity
  • 2 parts
  • Oropharynx
  • Laryngopharynx
  • Muscularis externa has skeletal
    muscle for swallowing
  • *Nasopharynx
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

What is the Oropharynx?

A

Oropharynx
* Immediately behind oral cavity
* Made of stratified squamous epithelium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

What is Laryngopharynx?

A

Laryngopharynx
* Inferior to oropharynx
* Made of stratified squamous epithelium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

What is the Esophagus?

A

Esophagus
* Connects pharynx to stomach
* Stratified squamous epithelium
(nonkeratinized)
* Mucous glands in submucosa
and mucosa secrete mucus
- Lubricates bolus of food as passes
through

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

What is the Muscularis externa of the Esophagus?

A

Muscularis externa
* Upper 1/3: skeletal muscle
* Middle 1/3: mix of skeletal and smooth
* Lower 1/3: smooth muscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

What is Hiatal hernia?

A

Hiatal hernia
* Superior part of stomach pushes through esophageal hiatus following weakening of diaphragmatic muscle fibers
- Acidic stomach juices are regurgitated, eroding wall of esophagus (= GERD, gastroesophageal reflux disease)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

What is Barrett’s esophagus?

A

Barrett’s esophagus
* Due to persistent exposure of acidic stomach contents
* Causes lower esophageal ulcers and precancerous epithelium

57
Q

What is the purpose of the stomach?

A
  • Food spends ~4 hours in stomach
    being churned into chyme
  • Mechanical digestion (churning)
  • Chemical digestion (digestive
    enzymes and HCl)
  • Some absorption takes place here
    (most absorption occurs in the small
    intestine)
  • Limited to water, alcohol, and drugs
    (aspirin)
58
Q

What is the lining of the stomach?

A
  • The lining mucosa is simple
    columnar epithelium
  • Made entirely of cells that produce
    bicarbonate-buffered mucus
    (protection)
  • Lining is dotted with many gastric pits
    which open into gastric glands (more
    later)
59
Q

What is the anatomy of the stomach?

A
  • Rugae (= “wrinkles”)
    Regions
  • Cardia
  • Fundus
  • Body
  • Pyloric antrum
  • Pylorus (= “gatekeeper”) with pyloric sphincter
  • Greater and lesser curvatures
  • Sphincters
60
Q

What is Rugae?

A

Rugae (= “wrinkles”)
* Folds of mucosa that increase surface area and allow stomach to expand
* Easily holds 1.5 liters of food, can hold 4 liters!

61
Q

What are sphincters?

A

Sphincters
* Thickened regions of muscularis externa
* Cardiac sphincter (near heart)
- Prevents food from moving back into esophagus
* Pyloric sphincter
- Controls release of chyme intoduodenum

62
Q

What are the muscularis layer of the stomach?

A

Muscularis externa has extra layer:
1. Longitudinal
2. Circular
3. Oblique →innermost

63
Q

What is the microscopic anatomy of stomach epithelium?

A
  • Mucosa is lined with simple columnar epithelium
  • Mucous neck cells
  • Gastric pits
  • Gastric gland
64
Q

What is Mucosa of stomach epithelium?

A

Mucosa is lined with simple columnar epithelium
* All secrete bicarbonate-buffered mucus
* Mucus protects stomach wall from acid and digestive enzymes

65
Q

What is the Mucous neck cells?

A

Mucous neck cells
* Secrete mucus (different from mucus produced by epithelium [above], function unknown)

66
Q

What are Gastric pits?

A

Gastric pits
* Regions where epithelium cups downward, meets with gastric gland

67
Q

What are Gastric glands?

A

Gastric gland
* Connect to lumen through gastric pit
* Contain specialized cells
- Parietal cells
- Chief cells
- Enteroendocrine cells
- Undifferentiated stem cells

68
Q

What are Parietal cells?

A

Parietal cells
* Produce and secrete 2 products
- HCl which destroys bacteria
- Gastric intrinsic factor (GIF) which is necessary for vitamin B12 absorption in small intestine
* Vitamin B12 is needed for production of RBCs

69
Q

What are Chief Cells?

A

Chief cells
* Produce and secrete pepsinogen (in-active form)
* Also secrete gastric lipase (enzyme)
- Fat digestion

70
Q

What is Pepsin?

A

Pepsin breaks down proteins in food
* It is created when pepsinogen mixes with HCl
* active version of pepsinogen
- gastrin stimulates release of HCl and pepsinogen
- Pepsinogen + HCl = pepsin

71
Q

What are Enteroendocrine cells?

A

Enteroendocrine cells (= “gut endocrine”)
* Release hormones
- Ex. Gastrin stimulates parietal cells to release HCl)

72
Q

What are Undifferentiated stem cells?

A

Undifferentiated stem cells
* Found at junction between gastric pits and gastric glands
* Because of harsh environment, stomach cells are replaced every 3-7 days

73
Q

What is the purpose of the small intestine?

A
  • Longest segment of canal at ~16 ft
  • Longer in cadavers than living people
  • Simple columnar epithelium
  • Site of most absorption and chemical digestion
  • Chyme move through via peristalsis
  • Is churned via segmentation
74
Q

What is the Duodenum

A

Duodenum (= “12 finger-widths long;” 5%)
* closest to stomach
* Shortest
* Receives a number of substances
- Chyme from stomach
- Digestive enzymes from pancreas
- Bile from liver/gallbladder

75
Q

What is the Jejunum?

A

Jejunum (= “empty;” 40%)
* Most absorption occurs here
* second part of small intestine

76
Q

What is the illeum?

A

Ileum (= “twisted intestine;” 55%)
* closest to large intestine
* Longest
* Absorption occurs here as well

77
Q

What are the wall layers of the small intestine?

A

All typical layers of the alimentary canal
occur in the small intestine
* Mucosa
* Submucosa
* External muscularis
* Serosa

78
Q

What is the total surface area of the small intestine?

A

200 m2
- large surface area = more absorption

79
Q

What gives the Small intestine a large surface area?

A

Has a very large internal surface area to increase absorption:
1. Length (approx. 16 feet)
2. Circular folds
- contain villi, which contain microvilli

80
Q

What are Circular folds?

A

Circular folds
* 1 cm tall
* Increase surface area and forces chyme
to spiral through small intestine
- This slowing allows for increased
absorption of nutrients

81
Q

What is villi?

A

Villi
* 1 mm tall
* Made of absorptive cells (= enterocytes)
* Have blood capillaries and a lymphatic
capillary called a lacteal

82
Q

What is Microvilli on enterocytes?

A

Microvilli on enterocytes
* 1 um tall
* Called brush border as well

83
Q

What are the features of the villi?

A

Associated features
* Lamina propria is highly vascular
* Allows for increased absorption
- Capillaries - Absorb proteins and carbs
- Lacteals
- Absorb fats (which are too large
to enter capillaries)
* Muscularis mucosa
- Moves villi within lumen to increase contact with nutrients

84
Q

What are the specialized cells of the small intestine?

A
  • Absorptive enterocytes
  • Goblet cells
  • Enteroendocrine cells
    *Intestinal crypts
  • Undifferentiated epithelial cells
  • Paneth cells
  • Duodenal glands
85
Q

What are Absorptive enterocytes?

A

Absorptive enterocytes
* Found in mucosa
* Majority of epithelial cells
* Lots of mitochondria
- Absorption of nutrients requires energy
* Abundant ER
- Assemble absorbed lipids into chylomicrons
- Lipid-protein complexes
- This structure allows lipids to enter lacteals

86
Q

What are Goblet cells?

A

Goblet cells
* Found in mucosa
* Secrete mucus
- Protects surface cells and lubricates chyme

87
Q

What are Enteroendocrine cells ?

A

Enteroendocrine cells
* Secrete hormones to control
the release of other substances (ex. CCK and secretin)

88
Q

What are Intestinal crypts?

A

Intestinal crypts
* Invaginations of mucosa, between villi
* Epithelial cells produce intestinal juice
- A watery liquid that mixes with chyme

89
Q

What are Undifferentiated epithelial cells (stem
cells)?

A

Undifferentiated epithelial cells (stem
cells)
* Intestinal crypts
* Rapid replacement of cells
* New lining every 3-6 days

90
Q

What are Paneth cells?

A

Paneth cells
* Intestinal crypts
* At base of crypt
* Secrete enzymes that selectively destroy
unwanted bacteria
* Help maintain healthy microbiota
* Role in protecting stem cells

91
Q

What are Duodenal Glands?

A
  • Duodenal glands have ducts
    that open into intestinal crypts
  • Found in submucosa of duodenum only
  • Secrete alkalinic mucus to neutralize acidic chyme
92
Q

What are the Lymphoid Tissue in Small Intestine?

A
  • The small intestine has many areas of lymphoid tissue
  • MALT = mucosa associated lymphoid tissue
    • In mucosal layer of small intestine
  • Aggregated lymphoid nodules (Peyer’s patches)
    • Located in submucosa of ileum
93
Q

What is the structure of the Duodenum?

A

Inputs to duodenum:
* Stomach contributes chyme
* Gallbladder adds bile
- Breaks down fats
- Bile duct and sphincter control release
* Pancreas contributes
- Digestive enzymes
- Pancreatic juice (bicarbonate) that neutralizes chyme
- Main pancreatic duct and sphincter control release
* Hepatopancreatic sphincter is the final control “valve”

94
Q

What happens when Chyme enters duodenum from stomach
and activates enteroendocrine cells?

A
  • Presence of fats
    stimulates release of.
    • Cholecystokinin (CCK) Signals release of stored bile
    • Breaks down fats for better absorption
  • Presence of acids stimulates release of…
    • Secretin Signals release of pancreatic juice
    • Neutralizes acids
95
Q

What is the anatomy of the Large Intestine?

A
  • Epiploic (= “membrane-covered”) appendages
  • Teniae coli (= “ribbons of the colon”)
  • Haustra (= “to draw up”)
  • Ileocecal valve
  • Cecum (= “blind pouch”)
  • Colon (4 parts)
96
Q

What is the Epiploic?

A
  • Epiploic (= “membrane-covered”) appendages
  • Fat-filled pouches on outside
97
Q

What is the Teniae coli?

A

Teniae coli (= “ribbons of the colon”)
* Longitudinal strips of smooth muscle
* Cause puckering into sacs = haustra

98
Q

What are the Haustra?

A

Haustra (= “to draw up”)
* Saclike structures

99
Q

What is the Ileocecal valve?

A

Ileocecal valve
* Connects ileum to cecum

100
Q

What is the cecum?

A

Cecum (= “blind pouch”)
* Vermiform appendix (off of
cecum)
- Stores beneficial bacteria

101
Q

What are the four parts of the colon?

A

Colon (4 parts)
* Ascending
* Transverse
* Descending
* Sigmoid

102
Q

What type of epithelium would you expect to find lining the large
intestine?

A

Simple columnar

103
Q

What is the anatomy of Microanatomy of Large Intestine?

A
  • No circular folds
  • No villi
  • Absorptive cells = colonocytes
    absorb primarily
    water/electrolytes
  • Lots of goblet cells (mucus)
  • Reduce friction of fecal movement
  • Intestinal crypts with stem cells
  • Epithelium is replaced every 7 days
104
Q

What is the rectum?

A
  • Connects sigmoid colon to anal canal
  • Has rectal valves
  • Transverse folds that prevent feces being
    passed with flatus (gas)
105
Q

What is the Anal Canal?

A

Anal Canal
* Epithelium transitions into
stratified squamous
* External anal sphincter
- Skeletal muscle, voluntary
control
* Internal anal sphincter
- Smooth muscle, involuntary
control

106
Q

What are Hemorrhoids?

A

Hemorrhoids
* Hemorrhoids = varicose veins
of the hemorrhoidal veins in
anal canal
- External and/or internal
hemorrhoidal vein swelling
* Caused by excessive straining
(baby or defecating)

107
Q

What are the Accessory Digestive Organs of Abdominal
Cavity?

A
  • Liver
  • Gallbladder
  • Pancreas
108
Q

What is the purpose of the liver?

A

The liver is a chemical processing plant
1. Digestive function: produces bile
2. Metabolic functions: processes blood
coming from stomach and intestines

109
Q

What is the digestive function of the liver?

A
  1. Digestive function: produces bile
    * Bile salts break emulsify fats in small
    intestine
    * Bile is stored in gallbladder until released
    into duodenum
110
Q

What is the Metabolic functions of the liver?

A
  1. Metabolic functions: processes blood
    coming from stomach and intestines
    * Stores some vitamins
    * Processes fats and amino acids
    * Inactivates drugs and toxins
    * Stores glucose as glycogen
    * Makes blood proteins
111
Q

What are the four lobes of the liver?

A

Has 4 lobes
* Right
* Left
* Quadrate
* Caudate

112
Q

What is the hepatic portal vein?

A

Hepatic portal vein
* Gathers blood from
digestive organs and
transports it to the liver

113
Q

What is the blood supply to the liver?

A

Blood supply
* Hepatic artery proper
* Hepatic portal vein
* Inferior vena cava

114
Q

What is the purpose of the Hepatic artery proper?

A

Hepatic artery proper
* Provides oxygen-rich blood to
liver

115
Q

What is the purpose of the Hepatic portal vein?

A

Hepatic portal vein
* Transports nutrient-rich blood
from stomach and intestines to
liver

116
Q

What is the purpose of the Inferior vena cava?

A

Inferior vena cava
* Removes blood from liver after
it has been processed

117
Q

What is Bile?

A
  • Bile, which is produced
    in liver, is transported
    through ducts to the
    gallbladder for storage
118
Q

How is the anatomy of liver organized?

A
  • Cells of the liver are organized into 50,000-100,000 hexagonally-shaped lobules
119
Q

How are blood vessels organized in the liver?

A
  • Blood vessels & ducts are organized into
    portal triads at corners of lobules
120
Q

What is in each triad?

A

Each triad contains
* Bile duct (transports bile out of lobule)
* Portal venule (transports nutrient-rich blood
into lobule)
* Portal arteriole (transports oxygen-rich blood
into the lobule)

121
Q

What are Hepatocytes?

A

Hepatocytes are the primary
cell of the liver
* Arranged into plates within
lobules
* Many functions
- Produce bile which is removed
via bile canaliculi
- Metabolize and store
substances from blood
* Great ability to regenerate

122
Q

What are Liver sinusoids?

A

Liver sinusoids
* Large capillaries between
plates of hepatocytes
* Site where arterial and
venous blood mix →blood is
carried to central vein

123
Q

What is the Central veins?

A

Central veins
* Drains blood from sinusoids out of liver

124
Q

What are Stellate macrophages?

A

Stellate macrophages = hepatic macrophages
* Move through sinusoids
* Destroy microorganisms that have made it through intestine and worn out blood cells

125
Q

How does bile move?

A

Bile moves from hepatocytes →bile canaliculus →bile duct

126
Q

What are the anatomical structures of the liver?

A
  • Hepatocytes
  • Liver sinusoids
  • Central veins
    *Stellate macrophages
127
Q

How does blood travel through the liver?

A
  • Blood in portal arteriole and Blood in portal venule (mix)
  • Blood mixes within sinusoid Gives hepatocytes access to oxygen, nutrients, etc
  • Blood leaves the lobules through the central veins
    on its way to the heart
128
Q

How do the liver and the gallbladder connect?

A
  • A series of ducts connect liver to gallbladder and duodenum
129
Q

What is the purpose of the gallbladder?

A
  • Gallbladder stores and concentrates bile
  • Bile = cholesterol, bile acids, salts, and bilirubin
130
Q

What are gallstones?

A

Gallstones
* Usually formed of cholesterol that precipitates out of bile while stored in gallbladder

131
Q

how is bile released?

A
  • A sphincter at the duodenum controls the release of bile into the duodenum
132
Q

What is the purpose of the pancreas?

A
  • Exocrine (digestive) function:
  • Acinar cells produce and secrete
    pancreatic enzymes/juices
    – Breakdown different food types
    – Neutralizes chyme (bicarbonate)
  • Pancreatic juices transported in
    main pancreatic duct and released
    by sphincter
  • Hormone controlling the release?
  • Secretin (produced by the small
    intestine)
133
Q

Endocrine function of the pancreas?

A

Pancreas also has endocrine function
* Different cells produce different hormones
- Beta cells produce insulin
- Alpha cells produce glucagon

134
Q

What is the Mesentery?

A
  • Mesentery: double-
    sided serous
    membrane that
    suspends organs
    within cavity
  • Contains blood
    vessels, nerves, fat
135
Q

What are the disorder of the GI tract?

A
  • Ulcers
  • Inflammatory Bowl Disease
  • Irritable bowel syndrome
  • Celiac disease
136
Q

What are ulcers?

A

Ulcers
* Crater-like erosions of the mucosa
* Most occur in pyloric region of stomach or
duodenum
* Used to think ulcers were caused by stress
* Now know they are due to bacterium:
Helicobacter pylori
- Binds to gastric epithelium →induces over-secretion
of acid and inflammation →ulcer
* Treatment: antibiotics

137
Q

What is the Inflammatory Bowl Disease?

A

Inflammatory Bowl Disease
* Two types
- Crohn’s Disease (more severe)
– Along entire intestine; primarily in terminal ileum
- Ulcerative colitis (less severe)
– Shallow inflammation large intestine; primarily in rectum
* General characteristics:
- Cramping, diarrhea, weight loss, intestinal bleeding
- Abnormal immune and inflammatory response to bacterial
antigens that normally occur in the intestine
* Can be treated with diet

138
Q

What is Irritable bowel syndrome?

A

Irritable bowel syndrome
* Affects large intestine
* Causes unknown (smooth muscle, nervous
system, inflammation…)
* Symptoms: abdominal pain, excess gas,
diarrhea, constipation, mucus in stool

139
Q

What is Celiac disease?

A

Celiac disease
* Autoimmune
* Gluten triggers and immune response, damages
villi of small intestine
* Treatment: gluten free diet

Anatomy (22 decks)

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