Fetal Pig and Rat Dissection LAP Day 3

Adam Nye Letina Jeranyama Fetal Pig and Rat Dissection LAP Day 3 Content: In this lesson, students will practice the theory we have been learning in the classroom. They will dissect the throat and brain regions of either a fetal pig or rat. First, students will open the throat. Usually, this will involve breaking open the ribcage, and then cutting up until the student reaches the mouth of the animal. Then, students will scrape away layers of muscle so that the trachea and vocal cords of the animal are revealed. If the trachea is exposed properly, and the trachea does not have a large amount of fluid inside, air can be pumped through the vocal cords to make the noises the animals make while they are living. Once students have finished with the throat, they will open the forehead using two cuts, making a plus sign. The first cut will stretch from the nose to the top of the skull, whilst the other traverses the span from ear to ear. They will then pick off pieces of skull to expose the brain. Learning Goals: Students will be able to use their dissection tools appropriately and effectively. Students will be able to identify the basic organs of the nervous system, as well as parts of the respiratory system (trachea, vocal cords). Students will be able to demonstrate lab safety. Rationale: We engaged with human anatomy for the vast majority of the third quarter, and we are about to embark upon a unit pertaining to evolution. As a result, this lab falls in a neat place; students will be able to practice the anatomical theory we learned in class, identifying and examining the same organs and body systems we spent a quarter learning about. At the same time, they will able to look back upon this dissection when we talk about shared characteristics and analogous parts during evolution. The learning experience that this lab affords students is authentic, and they work together in small groups. Through small groups they need to practice individual competency and group accountability. Finally, some of my students intend to move on to higher sciences as they progress through high school and then college. For these students, every lab experience will be a valuable foundation to support them as they are expected to engage with labs on an increasingly independent level over time. Assessment: Assessment for this dissection will be twofold. As students are physically engaging with the lab, I will be moving from group to group. Floating around the room in this fashion will afford me the opportunity to make sure students are acting in a manner befitting the experiment (maturely and safely) while also allowing me to encourage the students to connect theory and practice, particularly reinforcing the concept of structure and function. At the end of the lab, students will complete a relatively brief lab write up that encourages them to link the anatomy of the animal they worked with to human anatomy, while also tasking them with labeling several basic parts of their animal’s anatomy. In addition, the lab write-up will continue to hone student experimental design skills. Personalization and Equity: The open format of this dissection will allow me to float around the room, providing extra support where students need it and stimulating deeper thought where students are ready for it. Many of my students have not engaged with dissection before, so one of my concerns is that the vast majority of my students will need extra support, while I am only one teacher. Hopefully I can provide them with an adequate level of assistance. On another note, this lab is incredibly hands-on, tasking students with completing every facet of the dissection. They will need to work together and individually to accomplish the task, combining theoretical knowledge with active practice. Activity Description and Agenda: Learning Activity: Students will dissect their animals, exposing the trachea and examining the brain. Homework: Pre-read the lab write-up, come in with the hypothesis and background information sections complete. Mass Learning Standards: SIS1. Make observations, raise questions, and formulate hypotheses. Observe the world from a scientific perspective. Pose questions and form hypotheses based on personal observations, scientific articles, experiments, and knowledge. Read, interpret, and examine the credibility and validity of scientific claims in different sources of information, such as scientific articles, advertisements, or media stories. Reflection: The third day of dissection went very smoothly, though some students had trouble with the brain. Most of the students had already begun exposing the trachea during the previous period, and as such were able to complete the process relatively efficiently. Most of the student jitters present on the first day had worn off, and students were able to work in a professional fashion throughout the period. A few of the students even opened the throat so neatly that the vocal cords still functioned, and we were able to blow air through them to make noise. Some students did struggle to chip off the skull without damaging the brain. To expose the brain, students make two cuts in the shape of a plus sign on the skull, and then picked off the bone a piece at a time using tweezers. Several students were able to expose the brain and examine it, but many students damaged the brain after digging too deeply with the tweezers. In the future, I might try to highlight even further the importance of caution when attempting to expose the brain.