Digestive System Part C

Question 1

small intestine

what are the 3 regions of the small intestine?

Answer 1

1.) duodenum
2.) jejunum
3.) ileum (joins large intestine at ileocecal valve)

Question 2

small intestine

what is the name of the region of the small intestine that joins the large intestine?

Answer 2

• ileocecal valve

Question 3

small intestine absorption

what are the modifications of the small intestine for absorption?

Answer 3

• its length

other structural changes that provide a large surface area for nutrient absorption

• circular folds
• villi
• microvilli

Question 4

small intestine absorption

how does the small intestine’s length and other structural modifications provide a huge surface area for nutrient absorption?

Answer 4

• the length and other structural modifications of the small intestine provide a huge surface area for nutrient absorption by increasing the size of the surface area to that of a tennis court

Question 5

small intestine absorption

what are circular folds in the small intestine, and how do they help with absorption?

Answer 5

• permanent folds in the small intestine
• force chyme to slowly spiral through the lumen, allowing more time for nutrient absorption

Question 6

small intestine absorption

what are villi in the small intestine, and how do they help with absorption?

Answer 6

• finger-like projections of mucosa in the small intestine
• contain a dense capillary bed and lymphatic capillary - help with absorption by increasing the surface area for nutrient absorption

Question 7

small intestine absorption

what are microvilli in the small intestine, and how do they help with absorption?

Answer 7

• brush border with enzymes used for final carbohydrate and protein digestion
• help with absorption by increasing the surface area for nutrient absorption

Question 8

MALT

what is MALT?

Answer 8

-mucosa-associated lymphoid tissue

Question 9

MALT

what is the function of MALT?

Answer 9

• protects the intestine against microorganisms

Question 10

MALT

what are the components of MALT?

Answer 10

• individual lymphoid follicles
• Peyer’s patches (aggregated lymphoid nodules)

Question 11

large intestine

what are the 5 overall functions of the large intestine?

Answer 11

1.) complete absorption
2.) reclaim vitamins, water, and electrolytes
3.) no food breakdown occurs except what bacteria digest
4.) produce certain vitamins
5.) form and expel feces

Question 12

large intestine

what are the 4 layers of the large intestine?

Answer 12

1.) mucosa
2.) submucosa
3.) muscularis
4.) serosa

Question 13

large intestine

what are the 2 special features in the muscularis externa layer of the large intestine?

Answer 13

1.) teniae coli
- modified bands of longitudinal muscle
2.) haustra
- pocketlike sacs.

Question 14

large intestine subdivisions

what is the order of subdivisions in the large intestine, starting with the cecum and ending with the anus? (7)

Answer 14

1.) cecum
2.) ascending colon
3.) transverse colon
4.) descending colon
5.) sigmoid colon
6.) rectum
7.) anus

Question 15

large intestine

what is the mechanical digestion process that occurs in the large intestine?

Answer 15

• haustral churning

Question 16

large intestine

what are the 3 chemical digestion processes that occur in the large intestine?

Answer 16

1.) fermentation of carbohydrates
2.) production of some B vitamins and vitamin K by bacteria flora
3.) mucous secretion

Question 17

large intestine

what is the role of bacteria flora in the chemical digestion process in the large intestine?

Answer 17

• to ferment carbohydrates, produce some B vitamins and vitamin K

Question 18

large intestine

what is the result of the chemical digestion process in the large intestine?

Answer 18

• the final stage of digestion through bacterial flora

Question 19

large intestine

what is the function of haustral churning in the large intestine?

Answer 19

• to mix and move the contents of the large intestine through rhythmic contractions of the intestinal wall

Question 20

anal sphincter

what type of control is the internal anal sphincter under compared to the external anal sphincter?

Answer 20

internal anal sphincter is
- under involuntary control

external anal sphincter
- under voluntary control

Question 21

diarrhea vs. constipation

what is diarrhea?

Answer 21

• condition characterized by watery stools due to chyme and feces passing too quickly through the small and large intestines
• unable to absorb enough water and nutrients

Question 22

diarrhea vs. constipation

what is constipation?

Answer 22

• condition where feces remain in the colon for excessive periods of time
• leading to too much water absorption and resulting in hard and difficult-to-pass stool

Question 23

digestion of carbohydrates

where does the digestion of carbohydrates begin?

Answer 23

• begins in the mouth with salivary amylase

Question 24

digestion of carbohydrates

where does the digestion of carbohydrates continue after the mouth?

Answer 24

• continues in the small intestine with pancreatic amylase

Question 25

digestion of carbohydrates

what are starch and disaccharides broken down to during digestion?

Answer 25

• broken down to oligosaccharides and disaccharides

Question 26

digestion of carbohydrates

what are oligosaccharides and disaccharides further broken down into during digestion?

Answer 26

• further broken down into lactose, maltose, and sucrose

Question 27

digestion of carbohydrates

what is the final breakdown product of carbohydrates during digestion?

Answer 27

• monosaccharides such as glucose, fructose, and galactose

Question 28

digestion of carbohydrates

what is the final form of carbohydrates that is absorbed during digestion?

Answer 28

• only monosaccharides can be absorbed during digestion
• are absorbed into the bloodstream

Question 29

digestion of proteins

where does the digestion of proteins begin?

Answer 29

• begins in the stomach

Question 30

digestion of proteins

what breaks down proteins into large polypeptides in the stomach?

Answer 30

• proteins are broken down into large polypeptides by pepsin in the stomach

Question 31

digestion of proteins

where does protein digestion continue after the stomach?

Answer 31

• continues in the small intestine

Question 32

digestion of proteins

what breaks down small polypeptides and polypeptides in the small intestine?

Answer 32

• pancreatic enzymes break down small polypeptides and polypeptides in the small intestine

Question 33

digestion of proteins

what breaks down amino acids, dipeptides, and tripeptides in the small intestine?

Answer 33

• brush border enzymes break down amino acids, dipeptides, and tripeptides in the small intestine

Question 34

digestion of proteins

what is the final monomer that proteins are absorbed as?

Answer 34

• proteins are absorbed as amino acids.

Question 35

digestion of proteins

where are proteins absorbed into?

Answer 35

• absorbed into the bloodstream

Question 36

digestion of lipids

where does the digestion of lipids begin?

Answer 36

• digestion of lipids begins in the mouth by Lingual Lipase (minor) and
• in the stomach by Gastric Lipase (minor).

Question 37

digestion of lipids

what is emulsification in the context of lipid digestion?

Answer 37

• process of breaking down large fat globules into smaller droplets
• allowing for easier digestion and absorption of fats
• process is accomplished through the use of bile salts

Question 38

digestion of lipids

what are the 5 steps involved in breaking down fat into its monomer form, across the mucosal cell and into the lymphatic lacteal?

Answer 38

The steps involved in breaking down fat into its monomer form, across the mucosal cell and into the lymphatic lacteal are:

1.) Emulsification: Bile salts break down fat globules, coat them, and turn them into micelles.
2.) Micelle transport: The micelles cross the plasma membrane of the small intestine lining.
3.) Chylomicron formation: While crossing the membrane, lipids are converted back to triglycerides and packaged into chylomicrons.
4.) Chylomicron transport: The chylomicrons enter the lymphatic vessel.
5.) Conversion to monomer form: Once in the blood, the lipids are converted back to their monomer form.
Note: Steps 2-4 occur within the enterocyte (mucosal cell) of the small intestine.

Question 39

vitamins

What are the fat-soluble vitamins?

Answer 39

The fat-soluble vitamins are A, D, E, and K (ADEK).

Question 40

vitamins

How are fat-soluble vitamins absorbed?

Answer 40

Fat-soluble vitamins are transported like lipids and require the presence of dietary fat for optimal absorption.

Question 41

vitamins

What are the water-soluble vitamins?

Answer 41

The water-soluble vitamins are the B-complex vitamins (CB vitamins) and vitamin C.

Question 42

vitamins

How are water-soluble vitamins absorbed?

Answer 42

Water-soluble vitamins are absorbed by diffusion and are easily absorbed by the body.

Question 43

celiac disease

What is Celiac’s Disease?

Answer 43

Celiac’s Disease is a common malabsorption disease caused by an immune reaction to gluten.

Question 44

celiac disease

What does gluten do in individuals with Celiac’s Disease?

Answer 44

Gluten causes immune cell damage to the intestinal villi and brush border in individuals with Celiac’s Disease.

Question 45

celiac disease

How is Celiac’s Disease treated?

Answer 45

Celiac’s Disease is treated by eliminating gluten from the diet.