Digestive System for the American Bullfrog
How the System Works
- Mouth: The mouth is where the digestion begins. It can flick it's tongue out rapidly to catch flies and other moving or fast animals, insects etc. The tongue is also really sticky to make sure the animal doesn't escape.
- Esophagus/Gullet: This is where the food travels through to get to the stomach.
- Liver: The liver produces something called bile which breaks down lipids. It also stores glycogen which is used for energy.
- Gallbladder: The gallbladder stores bile.
- Stomach: The stomach breaks down the food by churning it. The stomach produces an enzyme called pepsin which begins to break down the food.
- Pancreas: The pancreas produces insulin, glycogen which controls the blood pressure.
- Small Intestine: The small intestine absorbs the nutrients, fats, proteins, and carbs.
- Large Intestine: The large intestine absorbs any extra water that is left in the waste.
- Cloaca: The waste is released from the cloaca.
American Bullfrog Menu
https://sites.google.com/site/bio379swhittemore/home/fall-session-2010/class-blog/group-3/anatomy-projects/bullfrogdissectionphotosandinformation
Respiratory System
Breathing as a Tadpole
Frogs begin their lives as a tadpole which are amphibians. Tadpoles live underwater and breathe using gills which are tiny flaps under their skin. The gills job is to extract the oxygen dissolved in the water. The gills will collect and trap the oxygen from the water, which will then be transferred to the rest of their bodies. Basically what happens is the tadpole will take in oxygen from it's mouth, the muscles in the tadpoles throat will transport the water to the gills. There are blood vessels in the gills and when the water comes into contact with them, the entire body receives the oxygen.
Transforming and Developing
As a tadpole begins to transform into a frog, they begin developing lungs, feet and they loose their tales. For a bullfrog, this transformation will take about three years. The tadpole will first loose its gills and develop lungs. While it still has its tail, it begins to use its lungs to breathe. They will come up out of the water to breathe. Also, their breathing is controlled by a pulsing in its throat.
Breathing as Frogs
Frogs breathe through their nostrils and the air breathed is pulled down into their lungs by their pulsing throats. They release carbon dioxide when they have body contractions. When a frogs lungs are filled with air, they become more buoyant in water. They also have blood vessels on their skin which will help them breathe too.
http://www.ehow.com/info_8767273_do-tadpoles-oxygen.html
http://www.ehow.com/how-does_4566846_frogs-breathe.html
http://www.thefrog.org/biology/breathing/breathing.htm
http://www.ehow.com/how-does_4566846_frogs-breathe.html
http://www.thefrog.org/biology/breathing/breathing.htm