Digestion/nutrition

Front 1

Digestion system performs 5 tasks:

Back 1

1.mechanical processing and motility

2. Secretion

3. Digestion

4. Absorption

5.elimination

Front 2

1. Mechanical processing and motility

Back 2

Breaking up, mixing, and transporting of food material

Front 3

2. Secretion

Back 3

Release of enzymes and hormones

Front 4

3. Digestion

Back 4

Chemical breakdown of food to molecules small enough to be absorbed in the gut

Front 5

4.absorption

Back 5

Passage of digested nutrients into the blood and lymph

Front 6

5. Elimination

Back 6

The expulsion of undigested and unabsorbed residues at the end of the gut

Front 7

Mouth

Back 7

-entrance to system

-food is moistened and chewed

-polysaccharide digestion starts

Front 8

Salivary glands

Back 8

-secretes saliva that contains:

+ lubricating mucus

+amylase (starch digesting enzyme)

+lysozyme (enzyme that kills bacteria)

+bicarbonate ions

Front 9

Pharynx

Back 9

Muscular contractions move food to esophagus by swallowing reflex

Front 10

Esophagus

Back 10

Muscular moistened tube moves food from pharynx to stomach (peristalsis)

Front 11

Liver

Back 11

Secretes bile, which emulsifies fats and bicarbonate ions

Largest internal organs in humans

Front 12

Stomach

Back 12

Muscular sac

-stretches to store food (can expand 20 times)

-highly acidic

-secretes mucus and gastric juice that contains Pepsinogen, the precursor to the protein digesting enzyme Pepsin, and hcl

Front 13

Gallbladder

Back 13

Stores and concentrates bile secreted by liver

Front 14

Pancreas

Back 14

Secretes enzymes (protease, amylase, lipase, nuclease) that breakdown all the major food molecules and bicarbonate ions that neutralize

Front 15

Small intestine

Back 15

-duodenum recieves secretions from liver, gallbladder and pancreas

-produces enzymes that complete digestion of proteins, carbohydrates, and nucleic acids

-absorbs products of digestion

Front 16

Large intestine

Back 16

Absorbs water and mineral ions

-secretes mucus and bicarbonate ions

-concentrates undigested matter into feces

Front 17

Rectum

Back 17

Stores feces

Distention stimulates expulsion of feces

Front 18

Anus

Back 18

End of system

Front 19

Molars

Back 19

Grinding up vegetation

Front 20

Premolars

Back 20

Rip, shred, grind

Front 21

Canines

Back 21

Ripping and tearing

Front 22

Incisors

Back 22

Grab food into mouth

Front 23

Carnivore teeth

Back 23

Big canines and premolars (for ripping and tearing flesh)

Molars not well developed

Front 24

Herbivore teeth

Back 24

Mostly grinding teeth (premolars and molars)

Very small canines and incisors

Front 25

Carnivore digestive tract

Back 25

Small cecum, short intestines

Front 26

Herbivore digestive tract

Back 26

Much longer intestines (due to lots of work to get nutrients out of the vegetation); large cecum (due to eating lots of veggies)

Front 27

Herbivore

Back 27

Deer, koalas, some birds

Invertebrates: crickets and caterpillars

Front 28

Carnivores

Back 28

Wild cats, Tigers, snakes, sharks

Sea stars, ladybugs, spiders

Front 29

Obligate carnivores

Back 29

Those that rely entirely on animal fl3esh for their nutrients

Lions/cheetahs

Front 30

Facultative carnivore

Back 30

Those that eat non animal food in addition

Dogs

Front 31

Omnivore

Back 31

Humans bear chickens

Cockroaches crayfish

Front 32

Humans and herbivores have ____________.

Back 32

Monogastric digestive systems.

Front 33

Ruminants:

Back 33

Mainly herbivores (cows sheep goats)

Diet consists of large amounts of roughage/fiber

Evolved digestive systems that help them digest vast amounts of cellulose

Four chambered stomachs

Front 34

Pseudoruminants

Back 34

Camels and alpacas

Front 35

Stomach =

Back 35

Major site for protein digestion in animals

Front 36

Protein digestion mediated by enzyme called _______

Back 36

Pepsin

Front 37

Pepsin is secreted by ________ in the stomach in inactive form called _______.

Back 37

Chief cells; Pepsinogen

Front 38

Pepsin: breaks _______ _______ and cleaves proteins into ______ _______.

Back 38

Peptide bonds; smaller polypeptides

Front 39

Pepsin also helps activate more _______, starting a _______ _________ _______ that generates more _______.

Back 39

Pepsinogen; positive feedback mechanism; pepsin

Front 40

Trachea has an opening called the _____, which is covered by a cartilaginous flap called the ______.

Back 40

glottis; epiglottis

Front 41

when swallowing, the _________, closes the _____, and food passes into the _____ and not the trachea

Back 41

epiglottis; glottis; esophagus

Front 42

Parietal cells:

Back 42

secrete hydrogen and chloride ions, which combine in lumen to form HCL

Front 43

HCL

Back 43

primary acidic component of stomach juices

Front 44

chemical digestion is facilitated by churning action of _____

Back 44

stomach

Front 45

the partially digested food and gastric juice mixture is called

Back 45

chime

Front 46

chime passes from _____ to _______ _________

Back 46

stomach to small intestine

Front 47

movement of chime is regulated by

Back 47

pyloric sphincter

Front 48

Small Intestine:

Back 48

long tube like organ w/ highly folded surface w/fingerlike projections called the villi

Front 49

surface of villi have microscopic projections called ______

Back 49

microilli

Front 50

____________ allow for nutrients to be absorbed from the digested food and absorbed into the blood stream

Back 50

microvili

Front 51

villi and microvilli increase the ______ ______ and increase _______ ________ of nutrients

Back 51

surface area; absorption efficiency

Front 52

absorbed nutrients in the blood are carried into the _____ _____ ______ which leads to the liver

Back 52

haptic portal vein

Front 53

3 parts of the Small Intestine:

Back 53

Duodenum, Jejunum, Ileum

Front 54

duodenum: C shaped fixed part

Back 54

separated from stomach by the pyloric sphincter which opens to allow chime to move from stomach to duodenum

Front 55

in duodenum: chime is mixed w/ _______ ______ in an alkaline solution rich w/ bicarbonate that neutralizes acidity of chime and acts as a buffer

Back 55

pancreatic juices

Front 56

Bile:

Back 56

digestive juice produced by liver; important for lipid digestion

Front 57

BILE is store and concentrated in

Back 57

gallbladder

Front 58

bile contains bile salts that

Back 58

emulsify lipids

Front 59

bile breaks down food particles in the chime into

Back 59

glucose, triglycerides, and amino acids

Front 60

Jejunum:

Back 60

bulk of chemical digestion and nutrient absorption occurs here

Front 61

Jejunum: hydrolysis of nutrients is continued while most of the ________ and ______ _______ are absorbed through the intestinal lining

Back 61

carbohydrates and amino acids

Front 62

Ileum:

Back 62

bile salts and vitamins are absorbed into blood stream

Front 63

Large Intestine 3 parts:

Back 63

cecum, colon, rectum

Front 64

cecum:

Back 64

joins ileum to colon and is receiving pouch for waste matter

Front 65

Colon:

Back 65

home to bacteria or "intestinal flora" that aid in digestive process

4 regions: ascending, transverse, descending, sigmodal

Front 66

colon functions:

Back 66

extract water and mineral salts from undigested food and o store waste material

Front 67

accessory organs:

Back 67

organs that add secretions (enzymes) that catabolize food into nutrients

*salivary glands, liver, pancreas, gallbladder

Front 68

essential nutrients:

Back 68

must be eaten, the body cannot produce them

Front 69

omega 3 alpha lindenic acid and omega 6 linoleic acid=

Back 69

essential fatty acids needed to make some membrane phospholipids

Front 70

vitamins=

Back 70

class of essential of essential organic molecules that are required in small quantities for enzymes to function; considered coenzymes

Front 71

minerals:

Back 71

inorganic essential nutrients obtained from food that help in structure and regulation; considered cofactors

Front 72

body can only synthesize ___ of the ___ amino acids

Back 72

11 of the 20

Front 73

reaction to smell, sight or thought of food

Back 73

first response is salivation

Front 74

Digestive phases:

Back 74

cephalic, gastric, and intestinal

Front 75

Cephalic phase

Back 75

controlled by neural response to the the stimulus provided by food; results in salivation and secretion of gastric uices

Front 76

gastric phase: begins when food arrives to _____

Back 76

stomach

Front 77

gastric phase: gastric acids and enzymes process ingested materials stimulated by:

1)

2)

3)

Back 77

1) distention of stomach

2) decrease in pH

3) presence of undigested material

Front 78

Intestinal phase:

Back 78

begins when chime enters the small intestine triggering secretions

controls rate of gastric emptying

Front 79

Hormonal responses to food:

Back 79

endocrine system controls response of various glands in body; most imp factors is stomach acid environment

Front 80

Negative feedback: during gastric phase:

Back 80

hormone gastrin secreted by G cells in response to the presence of proteins

Front 81

gastrin:

Back 81

stimulates the release of stomach acid of HCL which aids in digestion of proteins

Front 82

when stomach is emptied the environment need not be maintained and _______ stops the release of HCL

Back 82

somatostatin

Front 83

in order to neutralize the acidic chime, a hormone called _____ stimulates the pancreas to produce alkaline bicarbonate solution and deliver it to the duodenum

Back 83

secretin

Front 84

secretin acts in tandem w/ another hormone called _______

Back 84

cholecystokinin (CCK)

Front 85

CCK stimulates the ______ to produce the requisite pancreatic juices; also stimulates the ________ to release bile into the duodenum

Back 85

pancreas;gallbladder