Lab Handout (Lab Manual)

Scroll below for In-Person Lab

Pre-Lab

Before coming to lab:

1. Read the background material found in your lab manual.
2. Review the figures and videos listed below for Activities 1 & 2 that demonstrate the following key nutritional terminology: autotroph, heterotroph, intracellular or extracellular digestion, complete or incomplete digestive system, monogastric or ruminant.
3. Understand and apply the appropriate terms above to the nutritional strategies employed by Paramecium and Hydra. Not all of these terms will apply.
4. You will also want to be able to apply there terms to your In Lab work with Activities 3 & 4 below.

Activity One: Paramecium feeding (online videos) - See materials below

1. Use the online videos on the lab website to learn about how the Paramecium feeds, type of digestion, and structures involved. The videos will substitute steps 1-4 & 6-7 of this activity.
2. While watching the videos pay particular attention to: How/where does food enter the cell? How is the food digested and moved around the cell? How is waste excreted?

Paramecium:

• Description: ciliate Protozoan
• Habitat: stagnant freshwater
• Movement: cilia
• Nutrition: An oral groove is used to ingest nutrients and food vacuoles are responsible for digestion.
• Distinct Layers: The cytoplasm of protozoans can be divided into 2 layers.  The ectoplasm is the more clear outermost layer and the endoplasm is the central area surrounding all organelles.

VIDEOS OF PARAMECIUM FEEDING (#1 IS WHAT YOU WOULD HAVE SEEN IN LAB)

1. Paramecium eating Congo Red stained yeast cells.  As the yeast cells enter the Paramecium, they are encapsulated into food vacuoles.  When the yeast cells get digested by acidic enzymes, the red stain will change the yeast cells from red to blue.
2. At higher magnification you can see the movement of the cilia around the perimeter of the cell used for movement, but also along the oral grove into the gullet.
3. Closer still you can observe the cilia along the oral grove and the movement of food particles flowing into the cell.  A food vacuole forms as particles get encapsulated to form a vacuole, which are then is released into the cytoplasm of the cell.
4. After observing this feeding behavior, what terms can you apply to this type of feeding (Food Acquisition) and Digestion and Absorption of nutrients?

Activity Two: Hydra feeding (online videos) - See materials below

1. Use the online videos on the lab website to learn about how the Hydra feeds, type of digestion, and structures involved. The videos will substitute Steps 1-3.

VIDEOS OF HYDRA FEEDING (#2 IS SIMILAR TO WHAT YOU WOULD HAVE SEEN IN LAB FEEDING THE HYDRA DAPHNIA OR BRINE SHRIMP)

1. Video of Hydra eating a mosquito larva.  Note the overall structure of the Hydra and the smaller bulb-like stinging cells (nematocysts) along the tentacles.  Though the mosquito larva is quite large, the lack of a skeleton and jelly like body allows the Hydra a lot of stretching to fit food items through the mouth and into the gastrovascular cavity for digestion.  How does the waste then get out?
2. Green Hydra eating 3 water fleas (Cyclops).  The Green Hydra have green algal endosymbionts that provide some carbohydrates to the Hydra, but not so much that they still need to eat small zooplankton.
3. Describe how Hydra get food, ingest it, digest it, get the nutrients, and get rid of waste?
4. After observing this feeding behavior, what terms can you apply to to the Hydra in for feeding (Food Acquisition) and Digestion and Absorption of nutrients?

In-Lab

 

Activity Three: Bullfrog Dissection

In-Lab Dissection:

1. Groups will work as a table to dissect a bullfrog.  Follow the direction in your lab manual.  Examine the external of your frog. Are there any clues that let you know if this is a male or female frog? Find all the indicated external structures listed in your Lab Handout. 
2. Work through the rest of the directions (steps 2-11).  Answer all the questions and make the sketches on paper and/or take appropriate pictures of your dissection in order to label the indicated structures.
3. If you take your own pictures of your dissection, you will need to label the main structures digitally.  Scan/take pictures of your work from your lab manual and upload to Moodle with your answers to the end of Lab Unit questions.
4. Additional images and videos are provided below that may be helpful for drawing some of the anatomy and/or answering questions.
5. For your Post-Lab Assignment - Answer the End of Lab Unit Questions #1-6 in your lab manual.  The questions encompass Activities 1-4.  Do not copy and paste the information found in the lab manual, website, internet or AI.  Use your own words and interpretations. 

If you prefer not to participate in the Dissection:

1. Use the provided images found in the Frog Dissection (remote) PPT presentation to complete the material covered in Activity 3 in the lab manual.  These are nice clean images of a frog dissection.   
2. You will need to select View --> Slideshow.  Then click through different regions of the frog and organ systems to view all the indicated structures in your lab manual.
3. Additional images and videos are provided below that may be helpful for drawing some of the anatomy and/or answering questions.
4. Make sure to fill in the material requested in the lab manual and complete Steps 7-11.
5. Draw/sketch the internal anatomy from the online frog dissection and label all organs in correct location.  Do not take pictures of the online images to label.  Scan/take pictures of your work and upload to Moodle with your answers to the end of Lab Unit Questions (see below).  Please check to make sure your writing is legible.
6. For your Post-Lab Assignment - Answer the end of lab Questions #1-6 in your lab manual.  The questions encompass Activities 1-4.  Do not copy and paste the information found in the lab manual, website, internet or AI.  Use your own words and interpretations. 

Vertebrate Diversity in Heart Structure - Cool Interactive that includes Frog Hearts. Click on the Start Interactive, then on the Frog. The Systemic View will show you overall oxygenated and deoxygenated blood flow through the body. Then click on Heart Detail to see heart chamber details.

Images of Frog Dissections

	Frog Oral Cavity   a. Esophagus opening b. Vomerine teeth 1. Groove of the maxilla 2. Maxillary teeth 3. Internal nare 4. Eye ball 5. Eustachian tube opening 6. Jaw ridge 7. Underside of the tongue 8. Glottis 9. Cut muscle and bone
	Internal – Female Frog   1. Liver lobes 2. Heart 3. Ovary with eggs 4. Gall bladder 5. Small intestine 6. Stomach 7. Oviduct
	Internal – Male Frog   a. Large intestine b. Small intestine 1. Lung lobes 2. Heart 3. Liver lobes 4. Gall bladder 5. Stomach 6. Small intestine 7. Testis 8. Fat Body 9. Urinary bladder

Videos of a preserved bullfrog dissection

1. Review of external anatomy and internal mouth structures.  This video nicely shows the interesting attachment of the tongue and its function in capturing prey.  You will also see the 2 types of teeth used to help hold prey: the maxillary and vomerine teeth.
2. Review of Internal anatomy of the digestive, and the circulatory, respiratory and excretory systems.

Good written summaries and pictures of important frog structures and dissection.  The discussion of the mouth structures explain how the tongue is used to capture prey and points out the 2 types of teeth (maxillary and vomerine teeth).

 

Activity Four: Mammals' Teeth and Bird Bills

Part I: Mammals’ Teeth

1. Read the lab manual background material on Mammal's Teeth and the materials below..
2. You will complete Tables 9-1 and 9-2 under the guidance of your lab instructor. A lab handout will be provided.
3. In your lab groups, complete the rest of the Tables found on your lab handout.

Cool skull website – California Academy of Sciences – scroll down a little and click on “Enter the 3D gallery”

Skull Structures and Muscles of Mastication – Additional Information to help interpret feeding habit clues seen in skulls beyond looking at teeth.

Dental Formulas

Part II: Birds' Bills

1. Read the background material in your lab manual and the Bird Beaks and Bills information below.
2. In your lab groups, complete Table 9-5 on your lab handout. You will be examining bird skulls and bills with your group members.
   • For the bills provided, do you think that there might be another purpose other than diet for bill shape or color (defense, courtship display, etc.)? If yes, please explain.
   • Using the sheet provided below, Bird Beaks and Bills, identify at least three bird species (other than those you have already examined) and describe how their bill is designed for acquisition of food. If you do not know many species of birds, you can do a quick websearch of bird images from Audubon.org (click on the Explore Birds tab at the top of the webpage).  You may want to think of common backyard birds in your local region.

 Bird Beaks and Bills  - Explore the various types of beaks and bills. Birds have various bill/beak sizes and shapes for a variety of reasons. However, the most important factor in determining beak shape and size is feeding habits.

Post-lab

Additional Information

Gut Feelings Takes on New Meaning - Touch sensors in the gut lining respond to mechanical pressure and play an important role in digestion

What Big Teeth You Have - NCSU Biological Sciences researchers looking at tooth root surface area can help determine the size of primates.