Group Members: _____________________ _____________________________________

Date___________________ Period _______

Dissections Objective: In this two-week investigation, we will be looking at an invetebrate (grasshopper) and a vertebrate (frog). You will be focusing on the external and internal structures of these specimens. Standards: The standards covered for this lab is under the unit of Physiology.

o This lab will act as a fundamental basis and student reference for the physiology of human body systems.

o Students are to use investigation skills to explore the body systems.

Rubric: Completed frog coloring guides (4) 20 total

Dissection Vocabulary 10 Pre-dissection Research 8

Lab Questions 37 Reflections 15

Cleanliness of lab station & materials 10

Your score: Comments:

Assignment Points

Dissection Vocabulary: /10

Coloring Guides:

Grasshopper External /5

Grasshopper Internal /5

Frog Muscles /5

Frog Organs /5

Pre-dissection Research / 8

G Ex G In F Ex F In F Nv

Lab Questions /6 /4 /8 /14 /5

Reflections /3 /3 /3 /3 /3

Clean up /2 /2 /2 /2 /2

Section Totals

Total for lab: /100

Procedures:

You will be working in groups of 2 or 3. Each group has a dissection kit and one frog. You and your

partner are responsible for taking care of your materials and cleaning up your lab station. You and your

partner will each complete a daily log of detailed work and data collected throughout the week.

Dissection Kit

Number:

Received gloves: ______________

Dissection Vocabulary

We will be using the following new words throughout the dissection labs. You will need to be very

comfortable with this new language in order to communicate effectively with Ms. Pastor and your lab

partners.

A) My own dictionary: look up the words and write the definitions for your own reference.

o Anatomy: ___________________________

____________________________________

o Specimen: ___________________________

____________________________________

o Vertebrate: _________________________

____________________________________

o Invertebrate: ________________________

____________________________________

o External: ____________________________

____________________________________

o Internal: ____________________________

____________________________________

o Ventral: _____________________________

____________________________________

o Dorsal:______________________________

____________________________________

o Anterior: ____________________________

____________________________________

o Posterior: ___________________________

____________________________________

o Medial: _____________________________

____________________________________

o Lateral: _____________________________

____________________________________

o Inferior: ____________________________

____________________________________

o Superior: ____________________________

____________________________________

Using appropriate descriptions from the vocabulary refer to areas of a body. For example, instead of

saying “belly-side” or “front side”, we use the word “ventral”. For each of the figures below, label the

figures with the correct word that describes that area.

GRASSHOPPER-- COLORING GUIDES

Walking Legs Jumping Leg Claws Carapace

Hindwing Forewing Tympanum Spiracles

Antenna Abdomen Labrum Head

Thorax *Choose a color for each structure, color both box and structure

PRE-DISSECTION RESEARCH QUESTIONS

1) Like all insects the grasshopper has 3 body segments: Head, Thorax, Abdomen (p. 692-695)

a) Anterior segment is called the_____________________.

b) Middle segment is called the _____________________.

c) Posterior segment is called the ____________________.

2) List 4 parts contained in the head: (p.694)

1___________________ 2___________________ 3___________________ 4___________________

3) Which segment are the legs and wings attached to? __________________

4) Structures specialized for reproduction, digestion, respiration, and excretion are located in the ____________________

5) How does the grasshopper achieve the following senses?

a. Auditory (how does it hear?): ___________________________

b. Visual (how does it see?): ___________________________

c. Touch (how does it feel/touch?): ___________________________

d. Smell (how does it smell?): ___________________________

e. Taste (how does it eat?) : ___________________________

6) Describe where the grasshopper’s heart is located.

7) What does arthropod mean? (break it up into prefix-suffix) Grasshopper -- EXTERNAL STRUCTURES I. LAB QUESTIONS Locate and be able to identify the external structures of the grasshopper.

1) Is your grasshopper a male or female? How do you know? 2) Where are the bones? (Trick question… arthropods have an ______skeleton)

a. How many legs? ______

b. How many wings? _______

3) What is the function of the auditory membrane (tympanum)? Where is it located? 4) What is the function of the spiracles? Where are they located?

Data Table of Grasshopper Information

Length of grasshopper cm

Length of right jumping leg cm

Sex of Grasshopper (male or female)

III. REFLECTIONS

Write 3-4 sentences describing your experience today with grasshopper dissection. (What did you like about it? What did you dislike about it? Was there anything that you found really difficult? In what ways could you do better? What did you learn?) ____________________________________________________________________________________________

____________________________________________________________________________________________

____________________________________________________________________________________________

____________________________________________________________________________________________

IV. CLEAN UP GRASSHOPPER -- INTERNAL STRUCTURES

When using scissors, keep the scissor points just inside the body covering to avoid damaging the internal organs.

CAREFULLY cut along the ventral side of the grasshopper starting from the anus—along the abdomen—to the thorax.

Make a horizontal T cut at the thorax. Pin the grasshopper with 4 pins. If the specimen is a mature female, the interior spaces may be filled with slender eggs in the ovaries.

Inform your teacher if you find eggs—you may be asked to remove some of them.

I. LAB QUESTIONS

Locate and be able to identify the internal structures of the grasshopper:

1) Exoskeleton (remember—arthropods have their skeletal structure on the outside)

2) Muscular system—notice the many muscles, especially those connecting the wings & legs.

3) Digestive system - remove some of the lateral muscles and trachea as necessary without injuring other organs. Identify the following structures:

a. Esophagus d. Gastric caeca g. Rectum

b. Crop e. Stomach h. Anus

c. Gizzard f. Intestine

4) Circulatory system - heart

5) Respiratory system - trachea, spiracles

6) Excretory system - Malpighian tubules

7) Nervous system - brain, nerve cord

8) Reproductive system - testes, *ovaries, oviduct

9) How is the grasshopper heart different from the human heart?

10) How does the grasshopper get oxygen? What does it use to breathe?

III. REFLECTIONS

Write 3-4 sentences describing your experience today with grasshopper dissection. (What did you like about it? What did you dislike about it? Was there anything that you found really difficult? In what ways could you do better? What did you learn?) ____________________________________________________________________________________________

____________________________________________________________________________________________

____________________________________________________________________________________________

___________________________________________________________________________________________

IV. CLEAN UP FROG: External Structures*****************************************************************************

1) Record detailed observations of the feel and color of the dorsal and ventral body of the frog. Why do you think this would be a good survival trait?

2) How does the frog achieve the following senses?

a. Auditory

b. Visual

c. Touch

d. Taste- describe the position of the tongue

e. Smell

Cut the frog’s skin (integumentary coverings) at the ventral side starting from the anus up to the upper neck. Cut a T-section across from one armpit to the other. Take off the skin of the frog so that you can see the muscles.

EXTRA CREDIT for first group to have the skin in one complete piece…fingers and all!! Locate and be able to identify the major muscles of the frog.

3) What is the gastrocnemius for? 4) What do the striations (lines) of the muscles tell you about the movement?

REFLECTIONS Write 3-4 sentences describing your experience today with frog dissection. (What did you like about it? What did you dislike about it? Was there anything that you found really difficult? In what ways could you do better? What did you learn?) ____________________________________________________________________________________________

____________________________________________________________________________________________

____________________________________________________________________________________________

CLEAN-UP

Be sure to wipe down dissection trays and dry the dissection tools.

EC

FROG: Internal Structures **************************************************************************** Cut ventrally starting from the bottom of the abdomen to the bottom of the neck. Make a horizontal cut from one leg to the other. Make a horizontal cut from one underarm to the other. Pin open with 4 pins. Locate the major internal organs of the frog.

1) What is the first big organ that you see? How many lobes (parts) does it have?

______________________________________________________________________

2) Lifting up the liver, what organs get exposed? Name as many as you can see. Use your coloring

diagram to help you identify the organs. ______________________________________________________________________________________

______________________________________________________________________________________

3) What color is the fat body? ______________________ Stomach? ___________________________

Gall bladder? _________________ Where is it located? ____________________

Heart? ___________________________ Kidney?________________________

4) Is your frog a male or a female? ________________ How do you know? ______________________

______________________________________________________________________________________

5) Is the spinal cord on the ventral or dorsal side? _______________ Can you feel the vertebral

column? ____________ What is the vertebral column for? ___________________________________

6) Is the heart on the anterior or posterior side? ____________________________ Cut out the following organs:

a. liver & gall bladder b. heart (cut in half (creating ventral and dorsal halves)—to see how many chambers) How

many chambers? _____ c. lungs d. stomach e. small and large intestines intact (one piece)

7) Cut the stomach open. Did it have anything in it? ____________ Describe the texture of the inner

lining of the stomach. ______________________________________________________________________________________

______________________________________________________________________________________

8) Describe what the arteries and veins of the heart are connected to. Make a sketch of the heart in as much detail as you can here.

REFLECTIONS Write 3-4 sentences describing your experience today with frog dissection. (What did you like about it? What did you dislike about it? Was there anything that you found really difficult? In what ways could you do better? What did you learn?)

____________________________________________________________________________________________

____________________________________________________________________________________________

____________________________________________________________________________________________

CLEAN-UP

Be sure to wipe down dissection trays and dry the dissection tools.

FROG: Nervous System***************************************************************** Study and Removal of the Frog's Brain

Starting at the most anterior part of the head, the olfactory nerves connect to the nostrils and then to the olfactory lobes (A) where odors are processed. Just posterior to the olfactory lobes are two elongate bodies with rounded bases, this is the cerebrum (B), and it is the frog's thinking center. The cerebrum is the part of the brain that helps the frog respond to its environment. Posterior to the cerebrum are the optic lobes (C), which function in vision. The ridge just behind the optic lobes is the cerebellum (D), it is used to coordinate the frog's muscles and maintain balance. Posterior to the cerebellum is the medulla oblongata (E) which controls respiration, circulation, and other bodily functions; it also connects the brain to the spinal cord (F).

Complete the chart.

Brain Part Function Letter

Cerebellum

Cerebrum

Olfactory Lobe

Optic Lobe

Medulla Oblongata

Procedure: Removal of the Frog's Brain Turn the frog dorsal side up. Cut away the skin and flesh on the head from the nose to the base of the skull. With a scalpel, CAREFULLY scrape the top of the skull until the bone is thin and flexible. Be sure to scrape AWAY from you. With your scalpel held almost horizontally, carefully chip away the roof of the skull to expose the brain. Use scissors to cut away the heavier bone along the sides of the brain. To receive extra credit for removing the brain, you must present it to me. All lobes should be attached with as much tissue as possible present. GOOD LUCK!

REFLECTIONS Write 3-4 sentences describing your overall experience with frog dissection. What are some differences between the frog and humans. What are some similarities? ____________________________________________________________________________________________

____________________________________________________________________________________________

____________________________________________________________________________________________

CLEAN-UP

Be sure to wipe down dissection trays and dry the dissection tools.

EC