As part of the 7th graders current unit on the heart and circulatory system, we had a current parent come in (Dr. C – a Cardiac Electrophysiologist) to give a presentation to the whole 7th grade about the heart, pacemakers, heart health, and perform a dissection on the sheep heart. We set up a camera and projected it onto a large screen so that all the students could see to the dissection from anywhere in the room. Dr. C gave a wonderful presentation and we were lucky to have him share his experience and knowledge with us!
The next day, students had an opportunity to dissect a sheep heart and examine the structure and function of the heart up close. The students used sheep hearts that were frozen and then thawed prior to use instead of using preserved specimens. In my opinion, this provides a more realistic experience and is easier for the students to dissect. Since the heart was fresh, the cardiac muscle, arteries, valves, and veins were much easier to see and handle this way.
lab coat/apron/old shirt
pre-made labels using sticky notes or masking tape
Which way to the heart? Students learned about Heart Anatomy and Blood Flow (blog entry)
Pickle Dissection – Students learned how to use dissection tools (blog entry)
This is an updated version of an activity I have used with my 7th graders in the past. To get a true understanding of how blood circulates through their body, and to review the parts of the heart, I have the students sort the cards and place them in the right order starting and ending with the right atrium.
Students work in pairs placing the cards into the correct sequence on their desks. When they are ready to have their work checked, I start at the right atrium and go until I find a card out of place, then I stop and have them figure out what should come next and I’ll come back to check later. It will take several tries until they complete it correctly. When they are done, students can quiz each other using the cards or they can try the activity individually and have their partner check their work. Students can also use the Google Slides to review at home or print out a color set for their own use.
Heart Coloring Page – this is a great diagram of the heart. We color this together step-by-step in class when introducing the parts of the heart. Students can use pink and blue highlighters or colored pencils. (link)
We use blue only to distinguish deoxygenated blood from oxygenated blood in diagrams
I have the students hold the diagram in front of them and face each other so that they can see the right side of the heart matches their right side, but when the diagram is on their desk, the right side of the heart is on their left.
When we are done coloring, using their pointer finger, students trace the path of blood through the heart as I say each part in the correct sequence
This video has a simplified explanation, but is incorrect in stating that deoxygenation blood cells look blue, which adds to the common misconception students have about their blood being blue when it is in their veins.
You can ask them if they ever had their blood drawn, it doesn’t come out blue, it comes out maroon-ish or dark-red instead of bright red like when they get get a paper cut or scrape their knee.
The cow eye dissection is a great lesson to use as part of your unit on the nervous system and the five senses. There are several different ways you can use this lesson in the classroom.
Video & Model Only – share and discuss the video above. Using diagrams and clay/playdoh, students can create a model of the eye or use a scientific model to identify the structure and function of each part of the eye. Some students may be very uncomfortable watching the video and they can either turn around and listen or may have to leave the room.
Video, Model, and Demonstration – In addition to above, students can observe a cow eye demonstration. I like to use fresh specimens whenever possible, visiting your local butcher or farm is an option to look into instead of the preserved specimens, and generally are less expensive. Dispose of specimens properly.
Video, Model, Demonstration, and Dissection – In addition to above, students can work in small groups to perform a cow eye dissection. I like to use groups of 3 or 4 per dissection, this saves on specimens and it allows students to work at their own comfort level. Some students will only want to observe, some students want to do a little bit of the dissection, some will dive right in, and others will not take part at all and will have to do either the video/model only or the video/model and then observe your demonstration from a distance. Dispose of specimens properly.
Liberty Science Center: Traveling Science Workshop – Have LSC (or a local science museum) come to your school to conduct the lesson with your students.
Cow’s Eye Dissection | Grades: 6 – 10 Follow light on its journey through the eye. Led by a Liberty Science Center educator, students will pair off to perform cow eye dissections and in the process gain a deeper understanding of the structure of the human eye. NJCCCS: 5.1 C, 5.1.D, 5.3.A NGSS: LS1A: Structure and Function
Before starting the activity, have the students practice finding their pulses and counting. I find that they are more likely to feel their pulse on their neck (carotid) near their jaw.
For the lab, students will first get a baseline for their heart rate. They average their sitting and standing pulse and use that pulse to compare the other activities to. Each student will then make their own hypothesis, which activity will have the highest pulse? The lowest pulse?
Class management tip: We did each step of the lab together, and I kept time using the online stopwatch on the screen. That way, we were all jogging in place or doing jumping jacks at the same time.
Students recorded their data on to the excel spreadsheet and I collected and entered data onto my copy. Each student shared their data, one at a time, while the rest of us entered it. If you have google docs, you can add all data to the same shared Google Sheets.
The template that I have uploaded will automatically do the calculations for you and create a bar graph. You can turn that feature off, by deleting the formulas and graph, if you want students to learn how to use the formula for averages and create charts.
If you are having any issues with the excel sheet, or want to modify it, please reach out to your technology specialist for assistance.
For related lesson plans, please visit my Life Science page.
I used this hands-on activity as a review/reinforcement with my 7th graders and it really helped them understand the different blood types, about blood donation, and basic Punnett Squares. Plus they had fun playing the games and making up their own games.
All of the instructions and different games to play are explained in the handout. Some examples are: Who can donate? Punnett Square Practice, Identification, Memory, and Matching.
Other ways to use the cards:
Flashcards – Students can print their own at home and use them to study
You can set up a station/rotation to play the games as they are, or as ‘make your own’ game stations. Or a combination of both. Place one game at each station and have the students rotate every 7-10 minutes (see below for logistics)
Rotation Directions – students will rotate from table to table and learn to play the game at each station
Need a group of 4 students at each station.
When it is time to rotate, only 2 go to the next station, and 2 stay.
The 2 that stay are the experts on that game.
The 2 experts teach the 2 novices how to play when they rotate to the table.
When it is time to rotate, the 2 experts who stayed go to the next group, and the novices are now the experts and teach the 2 new novices that came to the station.
Quiz-Quiz Trade –
give each student a RBC card and have them identify it, then trade
give each student a blood-type card and ask for the genotype (ie AA or AO)
Or mix both decks and play both games
Find your Partner –
give half or your class Blood Type Cards and the other half of the class RBC cards and have them find the matching set
Interactive Links for further practice
Blood Typing Game – can you make the right choice? (link)
Are you my blood type? can you find the donor? (link)
Emergency Room – figure out the blood type and correct transfusion (link)