Digestive System

Question 1

An animal’s diet must provide:

Answer 1

chemical energy, organic monomers and essential nutrients

Question 2

4 classes of essential nutrients

Answer 2

essential amino acids, essential fatty acids, vitamins and minerals

Question 3

Essential Amino Acids

Answer 3

Body cannot synthesize, need through diet: tryptophan, methionine, valine, threonine, phenylalanine, leucine, isoleucine, lysine

Question 4

E.A.A complete

Answer 4

milk eggs, dairy… have all 8 amino acids

Question 5

E.A.A. incomplete

Answer 5

plants, needs complimentary diet

Question 6

malnutrition

Answer 6

deficiency in essential nutrients, can have negative health impacts

Question 7

undernourishment

Answer 7

inefficient chemical energy, will use up stored fat and carbs, break down own proteins and lose muscle mass

Question 8

primary energy storage

Answer 8

excess energy stored first as glycogen in liver and muscle

Question 9

secondary energy storage

Answer 9

fat in adipose cells

Question 10

Kwashiorkor
syndrome

Answer 10

body undergoing starvation, begins to cannabilize own proteins and causes excess swelling in stomach

Question 11

overnourishment

Answer 11

excess nutrients converted into increased body mass, first as glycogen then as fat

Question 12

ingestion

Answer 12

feeding or eating

Question 13

digestion

Answer 13

breaking food down into
molecules small enough to absorb

Question 14

Mechanical digestion

Answer 14

chewing or grinding, increases
the surface area of food

Question 15

Chemical digestion

Answer 15

enzymatic hydrolysis splits bonds in molecules by the addition of water
so they can pass through membranes

Question 16

Absorption

Answer 16

uptake of small molecules by body
cells

Question 17

Elimination

Answer 17

the passage of undigested material
out of the digestive system

Question 18

specialized
compartments

Answer 18

reduce the risk of an animal
digesting its own cells

Question 19

alimentary canal

Answer 19

digestive tube with regions that carry out digestion and absorption in a stepwise fashion

Question 20

Mammalian accessory glands

Answer 20

salivary glands, the pancreas, the liver and the gallbladder

Question 21

Saliva

Answer 21

lubricates food; made up of mucus, a viscous mixture of water,
salts and heavily glycosylated proteins

Question 22

Salivary amylase

Answer 22

breaks down starch

Question 23

tongue

Answer 23

forms food into a bolus for swallowing

Question 24

pharynx

Answer 24

junction that opens to both the esophagus and the trachea

Question 25

esophagus

Answer 25

connects pharynx to the stomach

Question 26

epiglottis

Answer 26

blocks entry to the trachea

Question 27

upper esophageal sphincter

Answer 27

guides bolus through esophagus

Question 28

Coughing

Answer 28

swallowing reflex fails, food enters windpipe

Question 29

peristalsis

Answer 29

rhythmic contractions of circular and longitudinal smooth muscles in the wall of the esophagus

Question 30

sphincters

Answer 30

valves that regulate the movement of material (chyme) between compartments

Question 31

stomach

Answer 31

stores food and processes it into a liquid suspension

Question 32

gastric juice

Answer 32

secreted by stomach made of HCl and pepsin: pH of 2 --> kills bacteria and denatures proteins

Question 33

chyme

Answer 33

mixture of ingested food and gastric juice

Question 34

Pepsin

Answer 34

protease that breaks peptide bonds to cleave proteins into smaller polypeptides

Question 35

Parietal cells

Answer 35

secrete H and Cl ions separately into the lumen

Question 36

Chief cells

Answer 36

secrete inactive pepsinogen

Question 37

pepsinogen

Answer 37

inactive zymogen converted to active pepsin through autocatalysis with HCl

Question 38

Mucus

Answer 38

coats the walls of the stomach and protects it from being eroded and digested by HCl and pepsin

Question 39

peptic ulcer

Answer 39

When walls of the stomach are exposed directly to HCl and pepsin

Question 40

Helicobacter pylori

Answer 40

causes gastritis and peptic ulcer disease by producing bicarbonate and ammonium ions

Question 41

heartburn

Answer 41

acidic chyme enters esophagus

Question 42

small intestine

Answer 42

longest and most enzymatic hydrolysis of macromolecules, composed of duodenum, jejunum, ileum

Question 43

duodenum

Answer 43

chyme from the stomach mixes with digestive juices from the pancreas, liver, gallbladder and the small intestine itself

Question 44

Enzymes of the pancreas

Answer 44

proteases: trypsin, chymotrypsin and carboxypeptidase; Pancreatic amylase, Pancreatic lipase, Pancreatic nuclease; bicarbonate

Question 45

Bile salts

Answer 45

digestion of fats, liver and stored in the gallbladder, route of excretion for bilirubin

Question 46

Villi and microvilli

Answer 46

increase surface area of intestine for increased absorption, made up of epithelial cells of mucosa

Question 47

hepatic portal vein

Answer 47

carries nutrient-rich blood from the capillaries of the villi to the liver, then heart

Question 48

The liver

Answer 48

regulates nutrient distribution, interconverts and detoxifies organic molecules

Question 49

Fat Globule

Answer 49

broken up into fat droplets of triglycerides by bile salts

Question 50

Fat Droplet

Answer 50

triglycerides broken up by lipases into fatty acids and monoglycerides

Question 51

chylomicrons

Answer 51

triglycerides coated in phospholipids/cholesterol/proteins to become water soluble for lymph transport, largest lipoprotein intestine --> liver --> adipose

Question 52

Lipoproteins

Answer 52

transport fats in circulatory system, composed of core of fat and cholesterol covered by phospholipids & proteins

Question 53

VLDL

Answer 53

carry (newly synthesized) triglycerides from the liver to adipose tissue

Question 54

LDL

Answer 54

carry cholesterol from the liver to cells of the body --> BAD

Question 55

HDL

Answer 55

collects cholesterol from the body's tissues, and brings it back to the liver --> GOOD

Question 56

Atherosclerosis

Answer 56

heart disease caused by high LDL to Hal ratio causing clogging of arteries

Question 57

large intestine

Answer 57

end of digestive system, contains colon, cecum, and rectum

Question 58

colon

Answer 58

completes the recovery of water, solidifying feces waste

Question 59

rectum

Answer 59

stores feces until they can be eliminated through the anus