Micro Quiz 6

what are 5 functions of the digestive system?

prehension

mechanical and enzymatic breakdown of nutrients

absorption of nutrients

synthesis and secretion of hormones

excretion of waste material

what is prehension?

ingestion followed by fragmentation

which has largest stomach? which has largest colon?

Ruminants have largest stomach

horses and rabbits have largest colons since thats where they do fermentation

what parts of digestive system are endoderm dervived?

epithelium

parenchymatous organs (pancreas and liver)

associated glands

what digestive system parts are mesoderm derived?

submucosa

muscle layers

serosa

mesentery

what parts of GI tract are ectoderm derived?

Stratified squamous epithelium (oral cavity and anus)

nerve plexi

what part of ruminant stomach is grandular?

abomasum

are cats and dogs stomach pretty much entirely glandular?

yes

where in digestive system find stratified squamous epithelium?

lips to non-glandular stomach

and the anus

in digestive system where find simple columnar epithelium?

glandular stomach and intesine

what are 5 structures of the oral cavity?

lips

cheeks

palate

tongue

pharynx

are salivary glands and tonsils in oral cavity?

yes

what is a species specific feature in oral cavity?

dental pad in ruminants

are some parts of the oral cavity keratinized simple squamous epithelium?

yes

what is epithelium like of lips and cheek?

keratinized stratified squamous

what is epithelium like of hard and soft palate?

keratinized stratified squamous epithelium

what part of tongue is keratinized?

dorsal side

why is the dorsal surface of the tongue irregular?

due to the presence of small outgrowths called papillae

what are 2 categories of papillae?

mechanical

gustatory

what are the 4 types/shapes of papillae on tongue?

filiform

fungiform

circumvallate

foliate

what 3 directions are skeletal muscle arranged in on tongue?

longitudinal, transverse and vertical

where do tastebuds occur?

in the epithelium of circumvallate, foliate and fungiform papillae

where is filiform papillae found? what does it look like?

dorsal surface of tongue (body and apex)

-numerous and slender/conical/threadlike projections

where is fungiform papillae found? what does it look like?

dorsum, margins, parts of ventral tongue

-small, round/mushroom shaped

where is circumvallate papillae found? what does it look like?

transition from body to root of tongue

-large and flat with deep sulcus on either side

where is foliate papillae found? what does it look like?

lateral near root of tongue

-folds of mucosa with transverse furrows

what 3 papillae type have taste buds in their epithelium?

circumvallate

foliate

fungiform

what influence the shape and structure of dentition?

type of food consumed

prehension

mastication

what are the 3 hard structures of a tooth? where located?

enamel-external surface above gumline

cementum-external surface below gumline

dentin- beneath enamel and cementum

what are 2 soft structures of the teeth?

pulp

periodontal ligament

what is function of periodontal ligament?

hold tooth in place

what is periodontium?

anatomical structures involved in resisting forces applied to teeth

whata re the 4 tissues that compose periodontium?

gingivae

periodontal ligament

cementum

alveolar bone

what 3 cells form the hard tissues of the tooth? what does each make?

ameloblasts-enamel

odonotoblasts-dentin

cementoblasts-cementum

what 2 cell types secrete the soft tissues of the teeth? what do they make?

fibroblasts- periodontal ligament

loose CT and nerves-pulp

what is the order of teeth layers? inner to outer

pulp

odontoblasts

dentin

enamel

ameloblasts

what do odontoblasts cover?

mesnchymal papilla

what are 2 teeth shape?

brachydont

hypsodont

describe brachydont teeth

short teeth that cease to grow after eruption

-have one or more roots embedded in an alveolus

-have neck and crown

who has brachydont teeth?

all teeth of carnivores

incisors of ruminants

teeth of pigs (except their canines)

describe hypsodont teeth

tall teeth that continue to grow after eruption

-no crown and no neck

who have hypsodont teeth?

horses

cheek teeth of ruminants

canine teeth of pigs

which tooth shape continues to grow after erruption? which dont?

do grow: hypsodont

dont grow: brachydont

what is saliva?

liquid secreted by salivary glands that contains water, salts, mucin, enzymes, IgA, lysozymem lactoferrin and suspended cells

what 3 important enzymes found in saliva?

amylase

maltase

lipase

what antibody found in saliva?

igA

what are 4 functions of saliva?

digestion

provide moisture and lubrication

local immunity

evaporative cooling

what ar ethe 3 major salivary glands?

parotid

sublingual

mandibular

what are the 6 intramural minor salivary glands?

lingual

palatal

labial

buccal

zygomatic (carnivores)

molar (cats)

what 3 secretion types can salivary glands be?

serous

mucous

mixed

are salivary glands lobulated?

yes (how know they are not a lymph node)

what is a mixed gland?

mucous and serous cells sharing a common duct system

what epithelium lines all ducts in body?

simple cuboidal

how tell if looking at parotid gland?

all serous acini

how tell looking at sublingual salivary gland?

mainly muscous glands with a few serous glands and few serous demilunes

what are the 3 adenomere shapes?

tubular

acinar

alveolar

what adenomere type is salivary glands?

acinar

what is the general organization of a tubular organ?

4 layers

1. mucosa

2. submucosa

3. muscularis externa

4. serosa

what are 3 layers of the mucosa?

inner epithelium

middle lamina propria

thing outer muscularis mucosa

how many layers is muscularis externa?

mostly 2 layers but in some places 3 layers

what are the 2 layers of the muscularis externa?

inner circular

outer longitudinal

when call adventitia?

when its outside cavity and is just CT without a mesothelium layer

when is it serosa?

when inside body cavity and has mesothelium layer outermost

what is the epithelial lining of tubular digestive organs mucosa like?

simple columnar and glandular

what is the lamina propria of tubular digestive organs mucosa like?

loose CT with blood vessels, lymphatics, lymphocytes and smooth muscle cells that support the epithelium

what muscle type is muscularis mucosa always?

ALWAYS smooth muscle

what does the submuscosa do in GI tubular organs?

facilitate motility of the mucosa

what does the submucosa of tubular organs in GI tract contain?

vessels

nerve plexus

lymphatic nodules

glands

what is serosa continuous with?

mesentary

omentum

peritoneus

what tubular organ is only partly serosa?

esophogus (other part is adventitia)

what tubular organ is only partly adventitia?

espohogus (other part is serosa)

what epithelium type does esophagus have?

stratified squamous epithelium

what type of muscle does esophagus have?

skeletal and smooth

what type of external covering does esophagus have?

both serosa and adventitia

can the esophagus be keratinized or not keratinized?

yes

-some species have keratin and others dont

what does the submucosa of esophagus contain?

mucous glands

what muscle find in esophagus muscularis externa?

skeletal only or combination of skeletal and smooth

is it mainly serosa or adventitia that covers esophagus?

mostly adventita

what animals have keratinzed esophagus?

horses

pigs

cattle

goats

sheep

what animals have nonkeratinzed esophagus?

cats

dogs

what animals have partly striated muscle in esophagus?

horses

pigs

cats

what animals have fully striated muscle in esophagus?

cattle

goats

sheep

dogs

what is simple stomach? who has?

stomach with glandular muscoa only

-carnivores and humans

what is compound multichambered stomach? who has?

Stomach with stratified squamous in forestomachs and glandular epithelium in abomasum

-ruminants

in compound multichambered stomach which epithelium type does each part have?

rumen: stratified suamous

reticulum: stratified squamous

omasum: stratified squamous

abomasum: glandular

what is a composite stomach? who has?

stomach with both glandular and stratified squamous mucosa

pigs and horses

what are the 3 compartments of a ruminant forestomach? describe each

rumen: largest with low papillae

reticulum: honeycomb mucosa

omasum: many leaves, butchers bible

are all compartments of a ruminants forestomach keratinized stratified squamous epithelium?

yes

what is function of rumen and reticulum?

mixing

eructation

regurgitation

movement of ingesta

absorption of VFA (volatile fatty acids)

what is function of omasum?

squeeze ingesta

liquifies to move to abomasum for further digestion

how tell rumen?

short papillae

no smooth muscle in papillae

what does the increased surface area of rumen allow?

passive absorption of volatile fatty acids

how tell looking at reticulum?

muscle is present only in the tip of the papillae

how tell looking at omasum?

very long papillae

muscle goes to top of papillae

what compartment of ruminant stomach acts as fermentation vat?

rumen

what part is the true stomach of a ruminant?

abomasum

where is cud formed in ruminant stomach?

reticulum

where does acid and enzyme digestion occur in ruminant stomach?

abomasum

which compartment of ruminant stomach removes excess water?

omasum