Fourth Quarter Biology Portfoliio

V. Conclusions: 1. Name two different functions of the skin The loose, thin skin of a Frog contains many capillaries, and serves a vital aid in gas exchange through the process of cutaneous respiration, due the small surface area of the lungs. Because of its permeability, the skin of a frog also allows for the absorption of water.

2. Name a function of the mucus glands.

The mucus glands of a Frog excrete a lubricant that keeps the skin moist in air, and aids in gas exchange. In some species, they also excrete foul tasting, or poisonous substances 3. How many arteries does a frog have?

The frog has three primary arteries, as well as many smaller arteries. The Carotid arches transport blood to the brain, the Aortic Arches transport blood the the body, and the Pulmocutaneous artery transports blood to the lungs. Other arteries include the renal artery, the gastric artery, the hepatic artery, the subclavian artery, and the iliac artery.

4. What is an adaptive value of the nictitating membrane?

The transparent, movable nictitating membrane protects the eyes of a frog from chemical, bacteriological, and biological agents, without impeding vision.

5. Name four structures that empty their discharge into the cloaca. (answers in bold below) The large intestine, the gonads (ovaries and testes), the urinary bladder, and the kidneys all discharge into the frog's cloaca.

6. Name two ways that a frog's forelimbs differ from it's hind legs.

The longer back legs of a frog posses a skeleton with several specializations for absorbing the forces created by jumping and landing, and webbed hind feet.

7. How is the tongue of a frog attached to its mouth?

The muscular tongue of a frog is attached to the cranial end of the mouth so that the tongue can be flipped out and used to snare prey.

8. Where does the opening of the Glotis lead?

The glotis is a small, rounded structure with a vertical slit, found just caudal to the tongue, which serves as the opening to the larynx and the lungs 9. How many chambers are there in a frogs heart.

The tri-chambered heart of a frog consists of the left atrium, which contains only oxygenated blood, the right atrium, which contains only deoxygenated blood, and the muscular ventricle, which contains both oxygenated and deoxygenated blood, pumping them throughout the circulatory system.

10. Name the three arteries that branch from the Truncus Arteriosus The Carotid arches transport blood to the brain, the Aortic Arches transport blood the the body, and the Pulmocutaneous artery transports blood to the lungs.

11. How many lobes make up the liver of a frog?

The large liver of a frog creates bile, and consists of three separate lobes; the right lobe, the left anterior lobe, and the left posterior lobe.

12. Why is the Gallbladder Green?

The gallbladder serves as a storage area for bile, which tints it green.

13. What is the main function of mesentery?

The mesentery is a small, thin membrane resembling a pastic wrap, which holds the small intestine in place.

14. What system does the kidney belong to? What is its main function?

The kidneys of a frog serve as it's primary excretory organs, filtering the blood of harmful chemicals, and converting toxic ammonia into urea.