Chapter 13 Digestion part 1 Flashcards
break up food molecules into smaller molecules that can be absorbed
digestive system
physical break up by chewing, mixing, churning
mechanical digestion
enzymatic break up of material
chemical digestion
transport of material across gut wall into bloodstream
absorption
ball of food that is swallowed
bolus
continuous tube from mouth opening to anus/cloaca
digestive tract
three subdivisions of digestive tract
buccal cavity
pharynx
alimentary canal
chamber receiving alimentary canal and urogenital products
cloaca
opening separate for digestive tract
anus
examples of accessory digestive glands
salivary glands, pancreas, liver
oral opening to palatoglossal arch or fauces
buccal cavity
buccal cavity features
teeth
tongue
palate
cheeks
roof of buccal cavity
palate
fishes primary palate
ceiling with no openings
tetrapod primary palate
nasal passage openings
anterior secondary palate
hard palate
posterior secondary palate (mammals)
soft/fleshy palate
characteristics of teeth
unique to vertebrates
enamel capped
epidermal and meschymal contribution to form teeth
homology with denticles/scales of primitive fish
above gingiva
crown of tooth
below gingiva
base of tooth
base in socket/aveolus
root
site of blood vessels and nerves
apical foramen
hard, crown surface, and ameloblasts
enamel
under enamel/centenum
dentin
dentin is formed from
odontoblasts
root surface which has annular growth
cementum
connects root to aveolar bone of socket
periodontal ligament
all teeth same
homodont
teeth are different
herterodont
who doesn’t have teeth
birds and turtles
teeth continuously replaced through life
polyphyodont
2 sets of teeth in life
diphyodont
what are flat teeth good for
crushing/grinding plant material or animals with shells
teeth for cutting flesh
blade like edges and serrations on edges
salamander larvae have what kind of teeth
cone shaped teeth
salamander adults have what kind of teeth
2-cusp teeth
some snakes and sharks have
reverse -curve teeth
hollow teeth modified for venom delivery
fangs
four types of teeth mammals have
incisors
canines
premolars
molars
incisors
cut
canines
puncture/ hold
premolars
grind/crush
molars
grind/crush
low crown
brachyodont
high crown
hypsodont
rounded cusps
bunodont
straight-ridges cusps
lophodont
crescent-shaped cusps
selenodont
specialized teeth for show/ territory defending/ attracting mates
tusks
tongue of lamprey/hagfish
from pharynx floor with keratinized teeth for rasping
fish tongues
lack muscular tongue
tetrapods tongue
mobile, hypobrachial origin, attached to hyoid apparatus
protract sticky tongue to capture prey
lingual feeding
embryonically pharyngeal pouches off lateral pharynx wall give rise to
thymus
parathyroid
tonsils
ultimobrachial gland
regions of alimentary canal
esophagus
stomach
intestine
cloaca/anus
4 layers of all regions of alimentary canals
mucosa
submucosa
muscularis externa
adventitia
inner layer made with epithelial lining and lamina propria and muscularis mucosae
mucosa
loose connective tissue layer that can have many things in it including nerve cells
submucosa
circular and longitudinal smooth muscle layers
muscularis externa
outer connective tissue layer
adventitia
gut lining epithelium embryonic origin
endoderm
smooth muscle, connective tissue embryonic origin
mesoderm
connects pharynx and stomach
esophagus
characteristics of esophagus
peristalsis
mucus secretion to aid food passage
stratified epithelium
smooth muscle posterior and skeletal muscle anterior
sites of temporary food storage along esophagus
crop
expanded segment posterior to esophagus
stomach
characteristics of stomach
food storage
food processing/disgestion
absorption
what can the stomach absorb
water
ions
vitamins
short chain fatty acids
internal lining folds of stomach
rugae
three regions of stomach
cardiac region
fundic region
pyloric region
at junction with esophagus
cardiac region
largest area of stomach
fundic region
parietal cells secrete
HCl
chief cells secrete
pepsinogen (inactive) becomes pepsin (active)
at junction with intestine
pyloric region
intestinal glands
crypts
folds in mucosa of small intestine
plicae circularis
projections of mucosa of small intestine
villi
there can be three defined regions of small intestine
duodenum
jejunum
ilium
shorter thicker region of intestine
large intestine
moves material along, mixes material
peristalisis
assists movement protects lining
mucus secretion
digestive enzymes from intestinal glands
intestinal juice
from duodenal glands to neutralize acidic chime from stomach
bicarbonate secretions
from pancreas via duct to duodenum providing digestive enzymes and bicarbonate
pancreatic juice
from liver/gall bladder and aids in fat digestion
bile
areas of immune/ defense structures
MALT, peyer’s patches, intestinal flora