4-Zoology-Organ-Digestion-Parts

orifice

Body openings {orifice}| are at mouth and anus.

perineum

Space {perineum}| between vagina and rectum has muscle and other tissue.

4-Zoology-Organ-Digestion-Parts-General

abdomen

lower trunk above hips {abdomen, human}.

bowel

large intestine {bowel}|.

breadbasket

abdomen {breadbasket}.

entrails

intestines {entrails}.

gastrointestinal tract

Mouth, esophagus, stomach, and intestines form a tube {gastrointestinal tract}| {GI tract}.

viscera

intestines {viscera}|.

vitals

Body has organs {vitals} necessary for life, such as heart, lungs, and brain.

4-Zoology-Organ-Digestion-Parts-Tissue

adventitia

Digestive organs have outermost connective-tissue coverings {adventitia}.

fascia tissue

Fibrous connective tissue {fascia, tissue} surrounds organ or body cavity.

parenchyma

Digestive organs have tissue {parenchyma}, not including coverings and supports.

4-Zoology-Organ-Digestion-Parts-Mouth

mouth

First, lips and mouth {mouth, body}| receive food.

maw

mouth {maw}.

tongue muscle

A muscular appendage {tongue muscle}| attached to mouth back has taste buds, pushes food onto teeth, and rolls food into boluses.

bolus

Tongue muscle pushes food onto teeth and rolls food into balls {bolus}. Muscles push bolus into pharynx.

4-Zoology-Organ-Digestion-Parts-Mouth-Pharynx

pharynx

Organs {pharynx}| after mouth receive Eustachian tubes and have swallowing reflexes.

palate

Mouth roof {palate}| is hard in front and soft in back.

hard palate

Palate front {hard palate}| has bone covered by mucosa.

soft palate

Palate back {soft palate}| {velum} has connective tissue and muscle. Soft palate can close opening to nasal cavity while swallowing.

uvula

Soft palate has one cone {uvula}| hanging down, which can swell, causing snoring.

tonsil

At throat back are two ovoid lymph-tissue regions {tonsil}|.

esophagus

After pharynx, one tube {esophagus}| goes to stomach. Opening esophagus stimulates peristalsis down esophagus, to carry bolus to stomach.

4-Zoology-Organ-Digestion-Parts-Mouth-Saliva

salivary gland

Mouth glands {salivary gland}| secrete watery or mucous saliva, to hydrolyze starch to dextrins or glucose and to moisten food.

parotid gland

Salivary glands {parotid gland} can be near ear fronts.

sublingual gland

Salivary glands {sublingual gland} can be under tongue.

submaxillary gland

Salivary glands {submaxillary gland} can be near jaw angle.

4-Zoology-Organ-Digestion-Parts-Teeth

teeth

Mouth cutting, grinding, and chewing units {teeth, mouth}| can have roots, cementum, necks, gums, and crowns. Teeth are incisors, cuspids, bicuspids, and molars.

dental floss

String {dental floss} can remove debris and bacteria from teeth.

dentifrice

toothpaste {dentifrice}.

dentition

People gain teeth sets {dentition} in sequence.

denture

People can need replacement teeth {denture}|.

4-Zoology-Organ-Digestion-Parts-Teeth-Problems

malocclusion

Upper teeth can not align with lower teeth {malocclusion}.

bucktooth

Front tooth can stick out {bucktooth}|.

4-Zoology-Organ-Digestion-Parts-Teeth-Bacteria

calculus on teeth

Bacteria can form tooth film {calculus, teeth}|.

cavity in tooth

Bacteria can dissolve tooth enamel {cavity, teeth}|.

tartar on teeth

Bacteria can make layers {tartar}| on teeth.

tooth decay

Bacteria can dissolve tooth enamel {tooth decay}.

4-Zoology-Organ-Digestion-Parts-Teeth-Kinds

incisor

People have eight front teeth {incisor}|.

cuspid

People have four cone-shaped teeth {canine teeth} {cuspid}|.

eyetooth

One pointed canine tooth {eyetooth}| is between incisor and premolar.

bicuspid tooth

People have eight flattened two-pointed small teeth {pre-molar} {bicuspid}|.

molar teeth

People have twelve large flat teeth {molar, tooth}|. The first molars are six-year molars, behind baby teeth.

wisdom teeth

The last four molars {wisdom teeth}| {third molars} can be missing or embedded. Wisdom teeth appear at 17 to 21 years old.

4-Zoology-Organ-Digestion-Parts-Teeth-Kinds-Age

permanent tooth

People replace baby teeth with new sets {permanent tooth}|. People have 32 permanent teeth.

baby tooth

Children have first teeth sets {baby tooth}|. The 20 baby teeth include 8 incisors, 4 cuspids, and 8 bicuspids.

milk tooth

baby tooth {milk teeth}.

4-Zoology-Organ-Digestion-Parts-Teeth-Layers

root of tooth

Teeth have parts {root, teeth} in jawbones, held with cementum.

cementum

Teeth roots are held in jawbone with glue {cementum}.

mesenchyme

Teeth have inner layers {mesenchyme} with nerves.

pulp of tooth

Inner tooth {dental pulp} {pulp, teeth} has blood vessels and nerves.

neck of tooth

Gums surround teeth bottoms {neck, teeth}.

gum in mouth

Teeth necks are in flesh {gum, teeth}|.

dentyne

Under enamel and in root is bone-like material {dentin} {dentyne}.

crown of tooth

Teeth have parts {crown, teeth} above gums. Grass eaters have crowns that go below gums {hypsodonty}. Leaf eaters have crowns only over top.

enamel of tooth

Crowns have hard, smooth, and white layers {enamel, teeth}.

4-Zoology-Organ-Digestion-Parts-Stomach

stomach

A muscular sac {stomach}| on trunk left side receives food from esophagus. Stomachs have region {cardiac region} near heart, large sac {fundus, stomach}, and pylorus. Stomachs have a smooth-muscle-ring sphincter at top opening, which closes after bolus enters. Stomach and digestive tract have inner mucosa, middle circular and longitudinal muscle layers, and outer connective-tissue layer. Stomachs hold 2.5 liters. Stomachs can absorb alcohol, aspirin, and poisons. Helicobacter pylori bacteria cause stomach ulcers.

craw

Birds and primitive mammals have stomachs {craw}| that store and break down food.

chyme

Peristalsis churns food to soup {chyme}. Chyme passes through sphincter to small intestine.

gastric gland

Stomach glands {gastric gland} secrete hydrochloric acid and proteolytic enzymes. Gastrin hormone controls stomach secretions.

mucosa

Stomach and digestive tract have inner mucous membrane {mucosa}|.

pylorus

Stomachs have a region {pylorus}| near small intestine.

vomiting reflex

Brain controls ability to eject stomach contents {vomiting reflex}|.

4-Zoology-Organ-Digestion-Parts-Intestine

intestine

After stomach comes small and then large intestine {intestine}|. Gut distension causes pain but squeezing, cutting, or burning does not cause pain.

lumen

Intestines have inside spaces {lumen, intestine}|.

4-Zoology-Organ-Digestion-Parts-Small Intestine

small intestine

After stomach is one folded tube {small intestine}|, 30 feet long, which absorbs almost all food materials. End sphincter allows material to pass to colon. Intestinal wall secretes enzymes to break up proteins. Glucose and amino acids have active transport into blood. Lymph absorbs fats. Small intestine has peristalsis and churning movements.

transit time

Food passes through small intestine eight hours {transit time}.

villus

Small-intestine mucosa has many cytoplasm fingers {villus}, to absorb sugars and salts.

4-Zoology-Organ-Digestion-Parts-Small Intestine-Connectors

mesentery

Small intestine attaches to body back wall by connective tissue {mesentery}|.

omentum

Fat and connective tissue {omentum}| are in front of intestines.

peritoneum

Connective-tissue membrane {peritoneum}| lines intestines and body cavity holding intestines.

peritonitis

Peritoneum can have bacterial infections {peritonitis}|.

4-Zoology-Organ-Digestion-Parts-Small Intestine-Regions

duodenum

Small intestine has first part {duodenum}|.

jejunum

Small intestine has second short part {jejunum}|.

ileum

Small intestine has long part {ileum}|.

4-Zoology-Organ-Digestion-Parts-Liver

liver organ

A large gland {liver, organ}| on middle right side secretes bile salts into small intestine. Liver stores and converts sugars and carbohydrates, receives amino acids and sugars from intestine via portal vein, makes urea, synthesizes plasma proteins, stores vitamins, detoxifies alcohol and ketones, and regulates and produces lipids and fatty acids.

gall bladder

Bladders {gall bladder}| under liver hold liver bile salts and release bile salts into duodenum, to break up fats and neutralize stomach acid. Secretin hormone can control bile stimulation. Precipitated-cholesterol gallstones can be in bile ducts.

bile

Gall bladders hold liver bile salts {bile}|. In duodenum, bile salts break up fats and neutralize stomach acid.

bile pigment

Hemoglobin breakdown products {bile pigment} can accumulate in jaundice.

4-Zoology-Organ-Digestion-Parts-Pancreas

pancreas organ

Under stomach, one gland {pancreas}| secretes enzymes {pancreatic juice} into duodenum, to break up proteins. Secretin controls pancreas.

islets of Langerhans

Pancreas cells {islets of Langerhans} {Langerhans islets} can secrete insulin and glucagon into blood.

4-Zoology-Organ-Digestion-Parts-Colon

colon intestine

After small intestine, wider intestine {colon, intestine}| {large intestine} curves up right side, across body-wall back, and then down left side. Colon removes water and has peristalsis and churning movements. Colon has 12-hour to 24-hour transit time.

cecum

colon beginning {cecum}|.

appendix of body

Cecum has a small tube {appendix, intestine}| at bottom.

sigmoid colon

Colon ends {sigmoid colon}| are holding regions.

rectum

A muscular tube {rectum}| connects to anus. Rectum distension stimulates defecation.

anus

Rectum has an end sphincter {anus}|.

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Date Modified: 2022.0225