On the Cutting Edge: Exploring Mammalian Organs

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Mammalian organ dissection offers an excellent opportunity for students to learn about anatomical structures and functions. It also allows students to explore the physiological links between organ systems and identify the general structures representative of mammals. Extending this activity to comparative dissection leads to an understanding of how organs differ among mammals, including humans.

Comparative dissection activities using preserved cow, pig, and sheep eyes help students better understand the mammalian eye. (Cow eyes are outstanding dissection specimens for students learning human eye structures.) Structural differences your students can observe include overall eyeball size; size and shape of the lens, iris, and cornea; cornea thickness; and tapetum coloring. Encourage your students to make careful observations and gain as much information as possible about each specimen they dissect.

Next, discuss possible adaptational reasons for the structural differences between the specimens. For example, differences in cornea thickness may correlate with animal height, and the size and shape of an eyeball correlates with that of the orbit from which it came. As an extension, have students research reptilian, amphibian, avian, or invertebrate eye structure. Then ask students to compare their findings and to discuss the structural similarities and differences between human eyes and the eyes of other organisms studied.


To help your students better understand the mammalian heart, consider a comparative dissection activity using preserved cow, pig, and sheep hearts. Since these organs belong to animals in the same class, students will observe many structural similarities among them. However, students will also observe differences among the organs in size, muscle thickness, and blood vessel size. During dissections, your students can obtain direct measurements of these parameters and record them.

While dissecting and comparing the specimens, students can discuss possible adaptational reasons for these differences. For example, reasons for differences in heart size include each animal’s size and activity level, and differences in blood vessel diameter could be due to differences in each animal’s cardiac output. As an extension activity, have students research amphibian, reptilian, and avian heart structures. Next, ask students to compare the number of chambers in nonmammalian hearts to the number of chambers in mammalian hearts. Students can research each animal’s activity level and discuss a possible correlation between activity level and blood circulation. To conclude the activity, have students compare their findings and discuss the similarities and differences between the human heart and the hearts of other organisms studied.

We continue to develop new, innovative dissection resources designed to meet your needs and exceed your expectations. Once your class has explored hearts and eyes, we offer some great options for further studies in mammalian anatomy. For example, our Carolina’s Perfect Solution® Pigs and Cats are our most popular animal specimens for studying tissues, organs, and systems to learn about human anatomy. And our Carolina’s Perfect Solution® Comparative Mammalian Organ Dissection Kit enables students to dissect and study several important mammalian organs.