Amphibians Flashcards
What are the 2 key characteristics of amphibians
Air filled cavity
Paired internal Nares
Bony elements of paired fins
What were the 2 air breathing adaptations for moving out of the water?
Increased vascularization of air filled cavity
Double circulation
What are the 3 living orders of class amphibia?
Apoda/gymnophiona - caecilians
Caudata - salamanders
Anura - frogs and toads
Summarize order Apoda
Wormlike appearance
Small dermal scales
small useless eyes
Internal fertilization
Summarize order Caudata
Limbs at right ang;es
small
Changing body form based on environment - can lose gills completely or lose lungs
Cutaneous breathing
Summarize caudata reproduction
Males produce gelatinous spermatophores
Females pick up sperm cap with cloaca
What is unique about Caudate development
Paedomorphosis - retention of juveniles characteristics in adult stage
Summarize order anura
Adults lack tails
Caudal vertebrae are fused into urostyle
Long and muscular hinds
What features demonstrate order anuras water/terrestrial existence
Gas exchange with water
Buoyancy
Gas exchange with air
Can support selves against gravity
Lose water to air
Cutaneous breathing
What is special about Anuran skin?
Highly glandular to keep skin moist and produce sticky secretions during mating
Breathable
What do granular glands do in amphibians?
Produce noxious or toxic secretions
What is special about terrestrial vertebrate skeletons
Modified to support against gravity
Jaw structure and muscles adapted for prey crushing
Must be strong enough to support movement on land
What is unique about the Anuran skeleton
Specialized for jumping and swimming
Extremely shortened body
-Fewer vertebrae
–Cervical
–Trunk
–Sacral
Pectoral girdle
Lighter skull
reduced back skull
Back legs modified for jumping
What are the 3 types of breathing employed by amphibians
Cutaneous - Skin
Buccal - Mouth
What are the inner surfaces in frog lungs divided into?
Faveoli
Describe positive pressure breathing
Actively pushing air into lungs
Rib cage does not expand
Rhythmic throat movements ‘gulp’ air and forces it backward
How does contribution to gas exchange remain constant?
Buccal and Cutaneous breathing supplement eachother when needed
Describe the Anuran heart
2 Atria
1 Ventricle
Spiral folds in conus arteriosus
Describe the Amphibian sensory system
Can be simple
Lateral line system - in all aquatic larvae, some salamanders and some adult anurans
How does amphibian reproduction workA
Anurans - external
other - mostly internal
Eggs lack resistant covering - must be wet
What is frog sex called?
Amplexus - can last days
