GI reptiles fish and amphibians Flashcards
Describe the reptile mouth oral cavity
Mucous glands:
- lubricate prey, help swallowing
Salivary glands:
- scatters in submucosa
- lubrication
Venom glands:
- immobilise prey
Describe the snake tongue
in sheath under epiglottis/glottis
forked
heavily keratinised
for olfaction
chemical scents => Jacobson’s organ
Describe the Jacobson’s organ
accessory olfactory organ
roof of oral cavity
vomeronasal nerve
What types of teeth are found in squamates?
acrodont - not replaced in lost
Pleurodont - shed and replaced
Describe snake teeth
2 maxillary rows
1 mandibular rows
point backwards
Describe chelonian teeth
no teeth
sharp, keratinised beak
Describe the cranial kinesis of squamates
Can move upper and lower jaws relative to cranium
Quadrate bone - loose articulation with lower jaw (pushes upper jaw upward when lower jaw is opened
Describe the snake skull
No mandibular symphysis
Describe the reptile oesophagus
thin
fragile
highly distensible
Describe the intestines in reptiles
Snake - relatively straight
Lizards, chelonians - can be convoluted
Describe the LI of herbivorous chelonians
heavily convoluted with partitions to increase time for microbial fermentation
Caecum has high optimal temp (basking essential)
What is the triad in snakes?
spleen, pancreas and gall bladder are close together
get splenopancreas in some
Describe the GI microflora of herbivorous reptiles
aerobic
anaerobic
gram -ve
gram +ve
yeast
protozoa
Describe fat storage in reptiles
little subcut fat
fat bodies (often in caudal coelom)
base of tail in lizards
Describe the sensory methods of food detection in reptiles
Visual
Chemosensory:
- olfaction
- vomerolfaction (Jacobson’s organ)
- gustation
Thermal:
- heat pits detect temp of prey
What animals are found in the order caudata?
newt
salamander
siren
What animals are found in the order anura?
toads
frogs
describe animals that are found in the order gymnophiona?
legless
look like worms or snakes
burrowers
from tropical areas
Describe the diet of amphibians
larval form are herbivorous
adults are carnivores - often invertebrates
Describe the tongue of frogs and salamanders
long, muscular, sticky end
Describe amphibian teeth
crowns curve towards pharynx to hold prey in
shed and replace teeth throughout life
Describe amphibian GI anatomy
Short, simple GIT
SI - enzymatic digestion (villi for absorption)
LI - water and salt absorption
Cloaca
Describe the digestive glands found in amphibians
Buccal cavity (mouth):
- mucous glands (lubrication)
- salivary glands (lubrication)
- intermaxillary gland (sticky compound on tongue)
Describe unique features of fish digestive anatomy
immobile tongue
no salivary glands
pharyngeal teeth in some species to grind food
gill rakers - retain food and protect gills
Diffuse pancreas (not single organ)
Swim bladder
Describe the swim bladder
Outgrowth of oesophagus
Used for hydrostatic equilibrium (buoyancy)
Physostomes:
- maintains connection with oesophagus
- gulp airs to fill bladder
Physoclistous:
- use capillary network as source of gases
- not connected to oesophagus
Say aaaaahhhh
good boy
hmmmm juicy booty
