Lp 36

Question 1

Bile does not require?

Answer 1

Enzymes

Question 2

-enzymatic degradation of foodstuffs
-reduces macromolecules into absorbable substances

Answer 2

Enzymatic hydrolysis

Question 3

-have molecules that are hydrophobic &hydrophilic at opposite poles
-emulsify fats (attach to fat droplets at one end & h20 at other)

Answer 3

Bile salts

Question 4

SI absorbs?

Answer 4

-digested food
-minerals
-h20

Question 5

H20, indigestible substances & bacteria pass into?

Answer 5

LI

Question 6

H20 & minerals are reabsorbed; the rest?

Answer 6

Recal matter

Question 7

-membrane -bound enzymes (on brush borders of SI microvilli) mediate last stage of protein digestion
-absorbed into mucosal cells via 2* transport (co- transported w/ na+)

Answer 7

Amino acids

Question 8

3 monosaccharides derived from carbs?

Answer 8

-maltose: glucose (x2)
-sacrose: glucose + fructose
-lactose: glucose + galactose

Question 9

-located next to carb enzymes
-work as soon as monosaccharides form

Answer 9

Carriers that transport sugars

Question 10

-unique
-derivates of lipid digestion are h20 insoluble
-combine w/bile salts to form micelles

Answer 10

Lipids

Question 11

-contain: f.a, monoglycerides, cholesterol & fat-soluble vitamins (A,D,E,K)
-outer surface is hydrophilic; interacts w/ h20 in lumen
-tiny
-diffuse b/w microvilli
-absorbed by intestinal mucosa

Answer 11

Lipids micelles

Question 12

? Litres reach intestines daily
? % absorbed in SI

Answer 12

-9L
-95%

Question 13

Fat-soluble & h20-soluble vitamins absorbed by?

Answer 13

Diffusion

Question 14

Do transport w/sugars & a.a.

Answer 14

Na

Question 15

-passively diffuses
-absorption of h20 increase k+ concentration in chyme

Answer 15

K

Question 16

-co-transport (anti-port) in exchange for HCO3-
-HCO3- excretion: one method of ridding the body of ++ co2

Answer 16

Cl

Question 17

-regulated by vit D
-only in duodenum
-decrease plasma {ca+} causes increase absorption

Answer 17

Ca

Question 18

-actively transported
-stored in mucosal cells bound to ferritin
-decrease plasma [fe] causes increase fe uptake
-carried in blood carried by transferrin

Answer 18

Fe

Question 19

-food moving from mouth to anus
-provided by smooth mm except in pharynx & upper 1/3 of esophagus (skeletal m)

Answer 19

Motility

Question 20

-autorhythmic
-influenced by local, hormonal & neural factors

Answer 20

Smooth m in GI tract

Question 21

Tonic movements last min to hrs

Answer 21

Movement is tonic & rhythmic

Question 22

-constrict lumen
-push food down GI tract
-alt. Contraction of adjacent segments
-1 direction

Answer 22

Peristalsis

Question 23

-nonadjacent segments alternately contract & relax
-food moves fwd & back
-mixing

Answer 23

Segmentation

Question 24

Alimentary canal has its own nerve supply, the responsibility of?

Answer 24

Enteric neurons

Question 25

Enteric neurons are semiautonomous & comprise most of the major?

Answer 25

Intrinsic nerve plexuses

Question 26

-sensory & motor neurons
-largely regulate glands & smooth muscle in mucosa

Answer 26

Submucosa plexus

Question 27

-between circular & longitudinal muscle layers of muscularis externa
-provide major n supply to GI tract wall & control GI tract motility
-control of patterns of segmentation & peristalsis is largely automatic, involving pacemaker cells & local reflex arcs

Answer 27

Myenteric plexus

Question 28

-mostly excitatory
-increases motility (peristalsis) & secretion
-relaxes sphincters to allow movements of foodstuffs along tract
-increases bile secretion

Answer 28

Parasympathetic innervation

Question 29

-inhibits motility
-constricts sphincters
-decreases secretions
-inhibits bile secretion

Answer 29

Sympathetic innervation