Oat Biology Ch 14: Digestive System

Front 1

Heterotriphic

Back 1

Humans are

Unable to synthesize own material

Front 2

For a hetertroph, what must happen to food?

Back 2

Must be ingested after which digestin can occur

Front 3

What does digestion consist of

Back 3

Degradation of large molecules to smaller molecules to be absorbed into bloodstream used by cells

Front 4

What is intracellular digestion

Back 4

Within cell

Front 5

What is extracellular digestion

Back 5

Within the lumen or tract

Front 6

What is the order of digestive system

Back 6

Oral cavity --> Pharynx --> Esophagus --> Stomach --> SI --> LI -->Anus

Front 7

What are accessory organs

Back 7

Salivary glands, pancreas, liver and gallbladder

Front 8

What kind of digestion does oral cavity have?

Back 8

Mechanical and chemical digestion

Front 9

What do salivary glands secrete

Back 9

Saliva

Front 10

What does saliva do?

Back 10

Saliva lubricates food to allow for swallowing and produce a solvent for food particles

Front 11

What kind of enzyme does saliva have

Back 11

Salivary amylase

Front 12

What does salivary amylase do

Back 12

Hydrolyzes starch to maltose (a dissaride)

Front 13

What is bolus?

Back 13

Moistened and chewed enough food

Front 14

What closes the esophagus from the stomach?

Back 14

Lower esophageal sphincter

Front 15

What cavity is the body of the esophagus in?

Back 15

Thoracic cavity

Has negative pressure relative to the enviornment on inhalation while abdominal cavity has relative positive pressure

Front 16

What is the gastrosophageal reflux?

Back 16

*Can occur after spontaneous transient lower esophageal sphincter relaxations not associated with swallowing

*Usually have decreased lower esophageal sphincter pressure which is why increased passage of stomach contents to esophagus

Front 17

What are the walls of stomach lined by

Back 17

Gastric mucosa

Front 18

What do the gastric mucosa contain

Back 18

Gastric glands

Front 19

What does the gastric mucosa do?

Back 19

Severe mucus to protect against the acidic juices which are at a pH of 2

Front 20

What do chief cells do?

Back 20

Secrete pepsinogen which convert to pepsin when in contact with HCl to breakdown proteins

Front 21

What do parietal cells do?

Back 21

Secrete HCl and intrinsic factor

Front 22

What is the intrinsic factor do

Back 22

Absorption of vitamin B2

Front 23

What sort of digestion does does the stomach do

Back 23

Mechanical and chemical digestion

(Churrning of stomach and enzymatic secretion)

Front 24

What is chyme

Back 24

Goes to SI

Front 25

What are the divisions of the small intestine

Back 25

Duodenum

Jejunum

Ileum

Front 26

What is the small intestine for

Back 26

Absorption

Front 27

What is the vili of small intestine for

Back 27

To make increased surface area for digestion. Vili has capillaries and lacteals

Front 28

How does blood from the digestive tract travel

Back 28

Enter the portal system of the liver where it is detoxified and stripped of its nutrients

Large fatty acids are reconverted to triglycerides in liver

Front 29

Where does most digestion in SI occur?

Back 29

In duodenum

Front 30

What does the internal mucosa of the small intestine secrete

Back 30

Lipases

*Aminopeptidoges (polypeptide digestion)

*Disarrachides (Maltose, lactose and sucrose digestion)

Front 31

What do lipases do?

Back 31

Fat digestion

Front 32

Waht does gastrin do?

Back 32

Produced in G cells of the duodenum

*Functions to stimulate histamine and pepsinogen secretion as well as increase gastric blood flow

*Stimulates the parietal cells to produce HCl, which denatures proteins and activates digestive enzymes

Front 33

What does intrinsic factor

Back 33

A secretion of the parietal cells that facilitates the absoprtion of vitamin B12 across the intestinal lining

Front 34

What is cholecystokinin (CCK)

Back 34

Produced and stored in the I cells of the duodenal and jejunal mucosa. It is involved in stimulation of pancreatic enzyme and somatostatin secretion as well as gallbladder contraction. Hunger suppresent

Front 35

What does the liver produce?

Back 35

Bile

Front 36

Where is bile stored

Back 36

Gallbladder

Front 37

Where is bile released

Back 37

Into the small intestine

Front 38

Does bile contain enzymes?

Back 38

No

Front 39

What does bile do

Back 39

Emulsifies fat, breaking down large globules into small droplets

Front 40

What does emulsification of fat do

Back 40

Exposes a greater surface area of fat to the action of pancreatic lipase/

Front 41

Can fat be digested without bile?

Back 41

No

Front 42

Waht are other functions of the liver

Back 42

*Store of glycogen

*conversion of ammonia to urea

*Protein syntehsis

*Detoxification

*Cholesterol metabolsim

Front 43

What enzymes does the pancreas produce?

Back 43

*amylase (carbohydrate digestion)

*Trypsin (Protein digestion)

*Lipase (Fat digestion)

*chymotripsin and enterokinase (Enterokinase cleaves trypsinogin to trypsin --> Trypsin activates other zymgoens (enzyme precursors)

*bicarbonate-rich juice to neutralize acidic chyme before duodenum

Front 44

Do pancreatic enzymes operate optimally at higher or lower pH?

Back 44

Higher

Front 45

How long is the large intestine relatively

Back 45

1.5 m long

Front 46

What does the large intestine do

Back 46

Absorb salt and water not already absorbed by the small intestne

Front 47

What does the rectum do

Back 47

Provide transient storage of feces before elimination through the anus