You will use this packet as your procedure packet as well as a study guide.

I will be checking review questions the next day so that you can finish any for HW.

Name: ______General Instructions

These procedures will be followed on a daily basis. Please keep referring to this page of your packet to make sure that you are following ALL directions!

Safety:

1. All members of your group MUST be wearing safety glasses/goggles.

2. Gloves are available and optional.

3. Absolutely NO FOOD, including gum.

Instruments:

1. Each group is responsible for one dissection try.

2. Your dissection tray will include the following tools:

a. Two pairs of scissors

b. Two probes

c. Two pairs of forceps

d. Eight (8) pins

Storage:

The frog will be studied for more than one class period. It is important to keep them moist and easily identifiable.

1. Make sure that the toe tag is securely attached to your frog and ALL GROUP MEMBERS’ NAMES are on the tag and easy to read. Please ask if you need a new tag.

2. Wrap your frog in a damp paper towel to prevent it from drying out.

3. Place your frog in your class period’s ziplock bag.

Cleanup:

1. Wrap any removed parts in a paper towel and discard them in a waste container. DO THIS BEFORE WASHING OUT YOUR TRAY!

2. Rinse and dry all dissection instruments, including your tray and return them to the proper storage location.

3. Spray down lab tables with antiseptic. 4. Everyone is responsible for cleaning up after themselves and NO ONE leaves the classroom until EVERYTHING is cleaned up!

Day One: External Structures of the Frog

Label the appropriate parts of the frog’s external structures.

Directions:

1. Place frog on the dissection try belly side down. Do not pin the frog at this time.

2. On the outside of the frog, locate and observe the following structures-turn the frog as needed to refer to the diagrams.

3. All organisms have sides to their bodies. Each side is given a specific “Scientific” Name. The head end is known as the anterior end, the rear end is known as the posterior end, the backside is known as the dorsal side, and the belly side is known as the ventral side.

4. Label the above diagram of the frog as appropriate. 5. Observe the frog’s exterior (outside). The frog has a head and trunk. The head contains the brain, mouth, eyes, ears, and nose. The trunk contains all of the frog’s internal organs.

Procedure:

1. Observe the following structures. You are responsible for know the structure, function, and location of all of the bold words. Complete the questions. Follow the bolded and underlined directions.

a. Look at the head found at the anterior end.

o Find the mouth- a large opening at the front of the head of the frog. It has both upper and lower jaws.

o Look at the nostrils- the two small holes just above the mouth.

o Find the eyes- The frog has three (3) eyelids. To close its eye, the frog must pull its eyeball into its socket

o Look at the eardrum known as the tympanum- the eardrum is a round membrane found on each side of the head.

 What is the frog’s ear missing? ______

 What does it look like to you? ______

b. Look at the frog’s trunk- The portion of the frog’s body located behind its head. c. Look at the appendages also known as the arms and legs.

o Find the forelimbs or front legs-

 What type of joint does its leg have? ______

o Find the forelimb digits or fingers

 How many fingers does your frog have? ______

o Find the hind limbs or back legs

o Find the hind limb digits or toes.

 How many toes does your frog have? ______

o Look at the skin- Frogs have very special skin! The skin of a frog IS NOT used for protection- Frogs drink and breathe through their skin.

o Look inside the mouth- Pry open the mouth with the probe and observe the mouth and throat. To loosen the jaw, you will need to cut the jaw (mandible) joint with the scissors.

 Find the maxillary teeth- They are found along the top jaw. Run your finger along the jaw line to feel that the tiny teeth feel like sand paper.

 Find the volmerine teeth- These are the two larger teeth found near the front of the roof of the mouth. They should be in the center. o Find the internal nostrils- These are holes found at the roof of the mouth. Use the probe to see how the internal and the external nostrils are connected.

o Find the throat- it’s the area at the back of the mouth. You MAY have to tilt your frog’s head back to be able to see the throat better.

o Behind the throat is the esophagus.

 What does the esophagus do? ______

o Look at the frog’s tongue- Notice that it is attached near the front of the mouth.

 Why do you think the tongue is attached to the front of the mouth? ______

Day One: Review Questions

Answer the following review questions from Day One’s Dissection for homework. These questions will be checked and graded upon completing the dissection project. You will also be responsible for knowing the material covered in these questions for your Practical Exam.

1. List the proper names for the following sides of the frog: a. Back Side- ______

b. Belly Side- ______

c. Rear End- ______

d. Front End- ______

2. ______are the two small holes outside the mouth.

3. The ______are two small holes in the roof of the mouth.

4. The frog has ______eyelids (number of eyelids).

5. The proper name of the eardrum is the ______.

6. The frog’s ear is not like a human’s. It is lacking an ______.

7. The three functions of the frog’s skin are to ______,

______and ______.

8. The ______teeth are located along the top ridge of the jaw. 9. The ______teeth are located at the center of the roof of the mouth.

10. The ______takes food to the stomach.

11. The tongue is attached to the ______of the frog’s mouth.

Day Two: Internal Structures of the Frog

Procedure:

1. Turn the frog on its dorsal side with the ventral side up. If you are unsure of which side is which, refer back to Day One. Hold the frog in place by pinning each hand and foot to the dissection tray. ONLY USE ONE PIN PER LIMB AND WAIT!

2. Follow the directions given by your teacher to cut the skin on the ventral side of the frog.

3. Pin the flaps of skin you just cut to the dissection tray. DO NOT CUT THEM OFF!!

a. Look at the abdominal muscles- the layer of muscles that make up the wall of the abdomen. NOW WAIT!

4. Follow the directions given by your teacher to cut the muscles. You will cut the muscles in the same fashion you did for the skin. Be careful and do not cut any organs! Be prepared to cut through bone!

5. Pin the flaps of muscle to your dissection tray the same way you pinned the skin down. Observe the organs that are in view.

Body Systems

1. Circulatory System

o Find the heart located in the center of the chest.

o Frogs have a ______-chambered heart. They have a right and left atrium (plural: atria) and a single ventricle.

o Find the liver- brownish organ that is divided into ______parts. It is the largest of the internal organs.  What is the function of the liver? ______

o Find the spleen- a reddish-brown oval structure (looks like a small pebble). Its function is to destroy bacteria, old red blood cells, and platelets. It also stores and releases blood in times of demand.

2. Respiratory System

o Find the lungs-they lie under and to the right and left of the heart.

 What is the function of the lungs? ______

--- CALL YOUR TEACHER AND WAIT! –

a. Remove ONE lung.

b. Cut the lung open along its length to observe the small chambers and sack-like structure of the lung.

c. Observe the lung under the stereoscope.

3. Digestive System

o Find the esophagus- Use your probe to see how the esophagus leads to the stomach.

o Find the stomach- this is a long white organ on the left side of the body cavity.

 What does the stomach do? ______ Why do you think the stomach is so large? ______

______

--- CALL YOUR TEACHER AND WAIT! ---

o Cut open the stomach lengthwise to observe the foods eaten by the frog.

o Observe the folds of the stomach lining.

 Did your frog have anything in its stomach? ______

 If yes, what did you find? ______

______

(Digestive System Continued…)

o Find the small intestine- small coiled tube attached to the bottom of the stomach. Be very careful when observing this organ! The pancreas is a very thin organ attached to the side of the small intestine and tears easily!

 What is the function of the small intestine? ______

o Find the large intestine- large tube that is attached to the end of the small intestine.  What is the function of the large intestine? ______

o Find the gallbladder- small round, dark (often greenish) sack attached to the back surface of the liver.

 What is the function of the gall bladder? ______

o Find the pancreas- ASK YOUR TEACHER FOR HELP- This is a flattened organ found in the tissue between the small intestine and the stomach.

 What is the function of the pancreas? ______

Day Two: Review Questions

Answer the following review questions from Day One’s Dissection for homework. These questions will be checked and graded upon completing the dissection project. You will also be responsible for knowing the material covered in these questions for your Practical Exam. 1. The layer of muscles that make up the abdomen are called the ______.

2. The function of the heart is to ______.

3. The frog’s heart has ______chambers.

4. The chambers of the frog’s heart are the ______, ______, and ______.

5. The liver is divided into ______parts.

6. The function of the spleen is to ______.

7. The function of the lung is to______.

8. The lungs re so small because ______.

9. The function of the stomach is to ______.

10. The stomach is so large because the frog ______.

11. The small intestine is coiled / straight (circle one)

12. The function of the large intestine is to ______. 13. The function of the liver is to ______.

14. The function of the gallbladder is to ______.

15. The function of the pancreas is to______.

Day Three: Internal Structures of the Frog Continued

Procedure:

1. Excretory System

o Find the kidneys- two reddish-brown, flattened organs lying on the back surface of the body cavity. You will need to remove the membrane covering them to get a good look. Kidneys are responsible for removing wastes and excess water from the body.

2. Reproductive System

 Is your frog male or female? ______

o If you have a female frog, find the ovaries- black and white in color. Ovaries produce reproductive cells called eggs.

(The Female Frog) o If you have a male frog, find the testes- each testis is a small oval organ attached to the front surface of the kidney. Typically they will be found with in the fat bodies near the kidneys. The testes produce reproductive cells called sperm.

(The Male Frog)

If you have a female frog, you will NEED to look at a male frog. If you have a male frog, you will NEED to look at a female frog.

o Find the fat bodies- fat bodies are long, finger-like yellowish tissue. They are responsible for storing fat.

2. Skeletal System

o Frogs have a single lower arm bone called the radioulna- the radius and ulna are fused together!

i. Cut through the skin and muscle of the left forelimb to expose the radioulna. CALL YOUR TEACHER FOR HELP!

o Frogs have a single lower leg bone called the tibiofibula- the tibia and the fibula are fused together!

i. Cut through the skin and muscle of the left hindlimb to expose the tibiofibula. CALL YOUR TEACHER FOR HELP!  How are the frog’s lower arm and leg bones different from ours? ______

Day Three: Review Questions

1. The function of the kidneys is to ______.

2. The ovaries are ______in color.

3. The testes are typically found near the ______.

4. The function of fat bodies is to ______.

5. The proper name for the lower arm bone is the ______. 6. The proper name for the upper arm bone is the ______.

7. The frog’s lower arm and leg bones are different from ours because they one have ______bone instead of two.

8. We dissected a ______frog. (Species of frog dissected).