Mammalian Digestive Systems

Abomasum

Abomasum

________: true glandular stomach where bacteria and pathogens are killed.

Rugae

________: folds of stomach with deep pockets, or gastric pits, contain.

Herbivores

________ have much longer intestines than carnivores.

Lacteal

________ (lymphatic vessel): allows for larger fat particles to enter, eventually dumped into blood.

Muscular nature

________ helps break up food.

Hydrochloric acid

________: kills microbes, dissolves particulate matter.

Omasum

________: lined by muscular folds, reduces particle size, absorbs water (and any leftover fatty acids)

Simple stomach

________: uses cecum at connection between small and large intestine.

Capillary

________: nutrients other than fat absorbed into blood.

Reticulum

________: form food bolus and initiate regurgitation.

Pepsinogen

________: converted to pepsin to begin protein digestion.

Rumen

________: digestive and fermentation vat, contains anaerobic microbes, site of fatty acid absorption.

Anterior end

________: functions primarily in ingestion.

Stomach

________: saclike organ evolved for storing food.

mutualistic microorganisms

Many herbivores have fermentation chambers, where ________ digest cellulose.

esophagus

Swallowing begins in ________ as voluntary action.

Large intestine

________: primary function to store and concentrate fecal matter and absorb some salt and water.

Middle portion

________: functions in storage and initial digestion.

Mouth

________: saliva begins initial processing of food.

fish lack

Some ________ a stomach, some birds (parrots and pigeons) lack a gallbladder.

Posterior part

________: functions in final digestion, absorption, and elimination.

Herbivores

________ must digest cellulose but lack cellulase.

Anterior end

functions primarily in ingestion

Middle portion

functions in storage and initial digestion

Posterior part

functions in final digestion, absorption, and elimination

Mouth

saliva begins initial processing of food

Pharynx/Esophagus

pathway to stomach only

Stomach

saclike organ evolved for storing food

Hydrochloric acid

kills microbes, dissolves particulate matter

Pepsinogen

converted to pepsin to begin protein digestion

Rugae

folds of stomach with deep pockets, or gastric pits, contain

Mucous cells

secrete mucus for protection

Parietal cells

secrete HCl (pH 1.5-2.5) HCL kills most bacteria & living cells; erodes plant materials; initiates change of pepsinogen to pepsin

Chief cells

secrete pepsinogen (inactive) which is converted by HCL into active pepsin

Stomach hormone

gastrin

Simple stomach

uses cecum at connection between small and large intestine

Reticulum

form food bolus and initiate regurgitation

Rumen

digestive and fermentation vat, contains anaerobic microbes, site of fatty acid absorption

Omasum

lined by muscular folds, reduces particle size, absorbs water (and any leftover fatty acids)

Abomasum

true glandular stomach where bacteria and pathogens are killed

Small intestine

nearly all digestion of food, and absorption of food and water

Villi

finger-like projections

Capillary

nutrients other than fat absorbed into blood

Lacteal (lymphatic vessel)

allows for larger fat particles to enter, eventually dumped into blood

Large intestine

primary function to store and concentrate fecal matter and absorb some salt and water