Download Lab #6: Animal Circulation

Lab #5: Animal Circulation
OBJECTIVES:
• Examine the circulatory structures from various animals
GENERAL PROCEDURES:
• Students will work in groups of 2-4 as instructed, but all students will complete their own lab
notebooks.
• Your notebooks should contain drawings of each slide, model and specimen (rat and pigeon),
with clear labels of structures to identify. Make sure to note the magnification you are using
to view the slides. You will also need to know the functions of each structure, but you do not have
to list function in your notebook.
INTRODUCTION:
In this Lab exercise, we will examine the anatomy and physiology of animal circulation. You by
now have read and heard about animal circulation, and the lab activities here will help add to your
knowledge. As we link the circulatory and respiratory function together, we focus on the role of the
circulatory system in distributing oxygen (among other things) to the cells of the multicellular animal,
and carrying the carbon dioxide (among other things) away from the cells of a multicellular animal.
We will exam a diversity of circulatory structures in the animal kingdom.
The basics of a circulatory system in general include a “pump” (typically a “heart”) that drives
oxygen carrying fluid and cells around the body (in either a cavity for open circulation or vessels for
closed circulation). This fluid carries oxygen to cells (used for aerobic respiration), and carries carbon
dioxide (metabolic by-product) away from the cells. We will look at the anatomy and physiology of
these structures (hearts, vessels, and blood cells)
Part 1: Slides & models
Identify the structures listed in bold below. Also note which phylum each of the organisms belong to.
Slides:
Human Artery-Vein
Locate the artery (thick walled very circular) and the vein (thinner walled, not circular)
Amphibian Heart - use dissecting scope
Amphibians have a 3-chambered heart. Identify the large single ventricle and the two atria (one
will be noticeably larger than the other due to the angle of the cut). Are any blood vessels
visible?
Models:
Mussel Heart (plastimount)
Mussels have an open circulatory system. Locate the heart, which pumps the circulatory fluid
into the body cavity to bathe the organs directly.
Also note the gills, mouth, foot & mantle.
Earthworm model
Earthworms have a closed circulatory system. Locate the 5 aortic arches (hearts) and the dorsal
blood vessel and ventral blood vessel.
Review from Animal Digestion Lab: pharynx, esophagus, crop, gizzard, intestine
Human Circulatory System model
Make a diagram that traces the pathway of a drop of blood from the vena cava to the systemic
capillaries in the human circulatory system.
Structures to include: vena cava, pulmonary venules and veins, left atria, right atria, left
ventricle, right ventricle, left lung, right lung, aorta, systemic arteries and arterioles, systemic
venules and veins, pulmonary arteries and arterioles, pulmonary capillaries, systemic capillaries.
Part 2: Animal Dissections
Use the Rat Dissection handout for instructions on proper analysis and dissection techniques.
In your notebook, make a drawing of the rat and clearly identify each of the structures listed below.
You will also need to know the functions of each structure, but you do not have list them in notebook.
Rat
Heart & arteries: right and left (R & L) atria, R & L ventricles, aortic arch, R & L common carotid,
subclavian, brachio-cephalic (innominate), thoracic aorta, abdominal aorta, renal (locate the kidney!),
R & L common iliac
Veins: posterior & anterior vena cava, R & L external and internal jugular vein, hepatic portal vein, R
& L renal vein
Review from Animal Digestion Lab: coelom, liver, esophagus, stomach, spleen, pancreas, small
intestine, mesentery, caecum, large intestine, rectum
Part 3: Demo Pigeon
Examine the demonstration pigeon at the front of the room. In your notebook, make a drawing of the
pigeon and clearly identify each of the structures listed below. You will also need to know the
functions of each structure, but you do not have to list them in notebook.
Pigeon
right atrium, right ventricle, left atrium, left ventricle, aortic arch, right & left subclavian arteries
Part 4: Mammalian Heart
Use the Heart Dissection handout for instructions on proper analysis and dissection techniques.
In your notebook, make a drawing of the heart (external and internal) and clearly identify each of the
structures listed below. You will also need to know the functions of each structure, but you do not
have to list function in your notebook.
Note: you will need to answer the questions presented in the Heart Dissection instructions in
your notebook.
Mammlian Heart
External Structures: pericardium, R & L atria, R & L ventricles, aorta, pulmonary artery, vena cava,
pulmonary veins, coronary artery
Internal Structures: R & L atria, R & L ventricles, pulmonary semilunar valve, aortic semilunar valve,
tricuspid valve (right atrioventricular valve), chordae tendineae, bicuspid or mitral valve (left
atrioventricular valve)
Part 5: Questions for Discussion/Conclusion section of notebook
Questions
1. How did the walls of the artery compare to the walls of the vein in the artery-vein slide? Why do we
see a difference n structure (think about function of each)?
2. In what capillaries is the blood of a human oxygenated? In what capillaries is the blood of a human
deoxygenated?
3. Compare the circulatory systems of the phyla we have viewed in this lab. Consider which are open
vs. closed, and differences in heart structure.
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