Amphibian Anatomy
The External Parts of a Frog
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Head
Front Legs
Fingers
Palm
Wrist
Lower Arm
Upper Arm
Elbow
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Trunk
Hind Legs
Thigh
Knee
Ankle
Sole
Webbing
Toes
The External Parts Functions
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The Frog body is divided into a head, a
short neck and a trunk. The head contains
a mouth, eyes, ears, nose, and, of course,
a brain.
Since their necks are so short they can’t
move their heads much.
Salamander
Skeletal anatomy of a frog
The Internal Parts of a Frog
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Male
Large Intestine
Small Intestine
Lung Lobes
Liver Lobes
Heart
Stomach
Gall Bladder
Testis
Fat body
Urinary bladder
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Female
Liver Lobes
Heart
Ovary with eggs
Gall Bladder
Small Intestine
Stomach
Oviduct
Digestive system
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The frog's digestive system starts in
the mouth with its tongue.
For the most part, frog tongues are
attached near the back of the jaw
and folded on the base of the mouth
with the tip of the tongue pointing
back toward its throat. Their tongues
can be flipped out very rapidly and
accurately in order to catch an
insect.
Most frogs do have tooth-like
structures which are attached to the
jaw and aid in breaking up the food
so that it can be digested.
The food then goes down their short
esophagus into the stomach, where
the food is digested. The waste
goes into the coiled, winding
intestines where it can be later
removed.
Cardiovascular system 
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-Some mixing of oxygenated and
deoxygenated blood occurs in
ventricle
They have a 3chambered heart,
arteries, veins, and
lymphatics.
A prominent ventral
abdominal vein is
present in amphibians
Reparatory System
They have four
modalities of
respiration:
1.- Branchial
2.- Boccopharyngeal
3.- Cutaneous
4.- Pulmonic
 Amphibian lungs are
paired
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-Gas exchange occurs through lungs,
gills, and/or the skin
-Some salamanders have no lungs
(secondarily lost)
-Adults have double circulation
-Both a pulmonary and a systemic
circuit
Excretory system
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The kidney of
amphibians is
mesonephric and
empties into a urinary
bladder.
The urinary blader of
some amphibians may
be biolobate.
Reproductive system
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Amphibians have paired
internal gonads that are
hormonally regulated.
The testes of the frog are
collection of seminiferous
tubules connected to the
mesenteric by collecting
ducts.
The amphibian ovaries are
located in proximity to the
kidneys as seen in higher
vertebrates.
Eggs are funneled into the
osteum of the oviduct and
then passed to the cloaca
Gender Determination
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Most not sexually dimorphic
-Size
-Color
Observe courtship
Candling abdomen for eggs
http://www.xlaevis.com/sexing.html
Gender Determination
Females
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More rotund body shape
http://www.telegraph.co.uk/
Gender Determination
Males
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Caudata
Crests, bright colors, tail swellings in
some during breeding season
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Anura
Vocal sacs, nuptial pads during
breeding season
http://www.xlaevis.com/sexing.html
Males are smaller than females
Resources
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Frog Biology http://www.biology.about.com/science/biology/library
/blfrogdissect.htm
Frog Biology http://library.thinkquest.org/11034/anat.htm
Anatomy of Amphibians http://www.lookd.com/frogs/anatomy.html
Images - http://wwwitg.lbl.gov/ITG/Whole.Frog/frog/frog.anatomy.html