The document discusses the anatomy of frogs, describing both their external and internal features. Externally, frogs have nostrils, an eardrum, and a nictitating membrane that protects their eyes. Internally, they have organs for digestion, respiration, circulation, and reproduction, including a three-chambered heart, lungs, liver, pancreas, intestines, kidneys, and sex organs like testes and ovaries.

1. Frog Anatomy

2. External Anatomy
• External nares or nostrils - Anterior
openings for the entry or exit of air.
• Tympanic Membrane - The eardrum -
receives sound waves
• Nictitating Membrane - A transparent
part of a frog’s lower eyelid that moves
over the eye to clean it and protect it.

3. External Anatomy

4. Mouth Anatomy
• Eustachian Tube Openings:
Openings in the mouth that lead
to tubes that connect to the
middle ear to equalize air
pressure
• Vomarine and Maxillary Teeth:
Used for holding prey
• Internal Nares (nostrils): Helps
with breathing

5. Mouth Anatomy
• Esophagus: Tube leading to
the stomach
• Tongue: Helps with grabbing
and swallowing prey
• Glottis: Tube leading to the
lungs

6. Mouth Anatomy

7. Internal Anatomy
• Heart - Pumping organ of the
circulatory system that has 3
chambers. The Left Atrium, The
Right Atrium, and the Ventricle.
• Stomach - Stores food and mixes
it with enzymes to begin
digestion.

8. Internal Anatomy
• Liver - Secretes bile and helps
digest food and filters blood.
• Lungs - Exchange point where
carbon dioxide leaves and
oxygen enters the blood;
helps the frog breathe.

9. Internal Anatomy
• Pancreas - Gland which secretes
digestive enzymes.
• Gall Bladder - Sac which stores
bile.
• Spleen - Organ in the frog’s
circulatory system that makes,
stores, and destroys blood cells.

10. Internal Anatomy
• Small Intestine - The principal
organ of digestion and
absorption of digested food.
• Large Intestine - Posterior
organ of the digestive system
which stores undigested food.

11. Internal Anatomy
• Cloaca - Organ through which
the frog’s digestive waste and
reproductive cells leave the
body.
• Fat Bodies - Masses of fat in the
body cavities of frogs. Needed
for hibernating and mating.

12. Internal Anatomy
• Kidneys - Organs that filter
the blood and remove the
wastes to make urine.
• Urinary Bladder - The organ
that collects and stores urine
until released.

13. Internal Anatomy
• Testes - Male sex organs that
produce sex cells (sperm).
• Ovaries - Organs of the female
reproductive system that
produce the eggs.

14. Internal Anatomy

15. Internal Anatomy