The Chicken and YOU!! Teachers Guide Purpose: Review of skeletal, muscle, and integumentary systems and inquiry into evolution focusing on homologous structures. Students will get to see and manipulate the various tissues which have been discussed in class. Identify the skin, connective tissue, muscles, tendons, bones, ligaments, and cartilage. Use their observations to explain how the tissues work together to produce movement. Concepts: Identify the structure and function of the various tissues associated with the skeletal, muscular, and integumentary systems. Explain how the bones, muscles, tendons, ligaments, and connective tissue all work together to produce movement. Explain the homology between the structures of the chicken wing and those of the human arm. Objectives: Identify the tissues of the chicken wing. Discuss how the skeletal, muscular and integumentary body systems work together to produce movement. Relate the anatomy of the chicken wing to the human arm. Standards: ILS I 12 A 5: Apply scientific inquiries or technological designs to explain tests of evolutionary evidence, analyzing acceptance of geologic and fossil records, researching comparative anatomy, embryology, biochemistry and cytology studies of analogous and homologous structures. Materials needed: (students in groups of 2) Masking tape Soap/paper towel Markers Dissecting kits - 1/group Dissecting trays - 1/group Dissecting pins – 4/group Protective gloves – 1 pair/student Safety goggles – 1 pair/student Chicken wings – 1 wing/group Student guides – 1/student Preparation guide: Mark the lab stations around the room with masking tape and pen. Lab stations will be in a logical sequence (1-14: class of 28), so that students can easily find their station. Every pair of students should have a 5’ by 2.5’ table top to complete their dissection. All materials, except the gloves and the student guides, will be on a tray at the dissecting station. One student from each group will come to the front to get a pair of properly sized gloves for both group members. The students can be called up five lab stations at a time to reduce the number of students at the front getting gloves. Pass out the student guides as the students are called up to get their gloves. Prepare a couple dissected wings to use for a demonstration. One wing could be dissected down to the bone and a second could be down to the muscle to show the majority of the tissues without working on the dissection in front of the class. Prepare youtube video before class. http://www.youtube.com/watch?v=SDANht5JPmg Individual Lab Set Up Described: Label the lab station with masking tape. Place all materials on a tray at each dissecting station. Each station needs a dissecting kit, dissecting tray, dissecting pins, 2 pair of safety goggles, and 1 chicken wing. Students will receive a pair of protective gloves and a student guide before completing the dissection. Time/length of lab: 50 minutes, students observe the prepared wings for tissues they are unable to see in their own and do the Making the Human Connection as homework 2 day activity, students dissect the first day. The wings can be refrigerated overnight if dissection is not complete. On the second day the students are able to finish up their dissection. The discussion questions are then completed and the students work in the Making the Human Connection in class. Safety issues: Raw chicken may be contaminated by Salmonella, a pathogenic bacteria. Wear gloves and keep your hands away from your face and mouth throughout the dissection. Be cautious when using sharp dissection tools. Thoroughly wash your hands, countertop and instruments with warm, soapy water after the dissection. Pre-lab Discussion Guide: Purpose for the day: You will have the opportunity to review and physically see the various tissues which have been discussed in class throughout our skeletal, muscular, and integumentary body system unit. You will identify the skin, connective tissue, muscles, tendons, bones, ligaments, and cartilage. You will also determine if the human arm and a chicken’s wing are homologous structures. To begin the lab you need to make a hypothesis, “Do you think the chicken wing and the human arm are homologous structures?” Carefully follow the directions, answer the questions, and label the diagrams on the student guide to successfully complete the activity. Expectations: Show youtube video to lead into the explanation of the procedure and proper dissecting techniques. All dissecting tools will be used in the proper manner: (You can demonstrate using a prepared wing.) o Probe- used to pick, poke, or move the tissue. (removing skin) o Scissors- cutting tissue (cutting tendons/ligaments, removing muscle) o Forceps- getting between/ under tissues o Pins – can be used to hold down the chicken wing. Dissecting Tips: Scalpels should not be used for bone or cartilage tissue work. Hold the scalpel as a pencil. Cut away from the body and away from other students. All dissection parts should remain within the dissecting pan. Properly dispose of all dissecting materials. o Students will get the teachers initials before disposing of their specimen. Safety: Raw chicken may be contaminated by Salmonella, a pathogenic bacteria. Wear gloves and keep your hands away from your face and mouth throughout the dissection. Be cautious when using sharp dissection tools. Thoroughly wash your hands, countertop and instruments with warm, soapy water after the dissection. Clean Up: Dispose of chicken parts and gloves in the garbage! All in back garbage can! Wash your lab station and equipment with warm, soapy water. Dry with a paper towel. Return all equipment to the proper place. Thoroughly wash your hands with warm, soapy water. Post-lab Discussion Guide: Questions to guide discussion: Explain the characteristics of the tissues observed in the chicken wing. What were those tissues connected to and what is their specific function? The students would then be asked to explain how the tissues cause movement; specifically, how do muscles work if they only have the ability to pull or contract. See answer key below for answers to discussion questions. If the lab is not finished: If the students do not have sufficient time to complete the dissection I will have previously dissected a wing to show them the various tissues they were unable to identify or see. Discussion questions can be completed as homework to be discussed the next day. Preview of tomorrow: “Making the Human Connection” activity will be completed the next day. This activity introduces the students to homologous structures which prepares them for the next unit on evolution. The activity will be followed by a review for the unit exam on the skeletal, muscular, and integumentary systems the next day. Adaptations for Students with special Needs: If the student is unable to safely use a scissors or scalpel the student will be placed with a partner who can complete the dissection portion of the activity while the student fills in the student guide. For the students who require additional time to complete tasks I will provide a chicken previously dissected so that they can simply look at the wing and identify the different structures. Lab Diagram: ANSWER KEY: Write a Hypothesis: Do you think the chicken wing and the human arm are homologous structures? If the human arm is or is not (circle one) homologous to the chicken wing, then during the dissection I will see structures throughout the wing which are not found in the human arm. The shape, size and structure of the bones or muscles in the wing may also be different between the chicken wing and human arm. Safety: Raw chicken may be contaminated by Salmonella, a pathogenic bacteria. Wear gloves and keep your hands away from your face and mouth throughout this investigation. Be cautious when using sharp dissection tools. Materials Dissecting kit Dissecting tray Protective gloves Safety goggles Chicken wing Procedure 1. Wash and pat chicken wing dry and place it in the dissecting pan. Part A: Comparing the External Structure and Function 2. Sketch the external structure of the chicken wing and label the following parts: upper wing, lower wing, and wing tip. Part B: Examining the Skin 3. With your fingers, pull the skin of the upper wing away from the pinkish muscle. The now-visible film-like tissue that attaches the skin to the muscle is called the hypodermis. The hypodermis is the connective tissue layer underlying the dermis of the skin. Compare the characteristics of the outer layers of the skin (epidermis & dermis they stay together) to the hypodermis. What is the function of the layers? Record your observations here. Layer Characteristics Hypodermis (Connective tissue) Clear, very thin sheet like Epidermis and Dermis Thicker tissue; white/pink Function Holds the outer skin layers to the muscle, helps facilitate movement Dermis -contains the blood vessels, supplies nutrients for the muscles and bones. Epidermis protects against infection and injury, barrier from the outside world. 4. Completely remove the rest of the skin from the upper part of the chicken wing by pulling and using the scissors to cut the skin away from the muscle. Be careful not the cut into the muscle, tendons, or ligaments as you remove the skin. 5. Remove the skin from the lower wing. Part C: Examining the Muscles 6. With your fingers, gently separate the muscles from each other. Notice the layers of loose connective tissue between the muscles. 7. Find the two groups of muscles in the upper arm. Hold the arm down at the shoulder, and alternately pull on each muscle group. Indicate in Figure A which muscle is the bicep and tricep and which muscle flexes and which extends the nearest joint. Bicep - flexes Figure A Tricep - extends 8. Find the muscle groups of the lower arm. Hold down the arm at the elbow, and alternately pull on each muscle. Why are there so many muscles? The fine, detailed movements of the bones in the wing tip require a greater number of muscles in the lower wing to control this movement. Part D: Examining the Tendons, Bones, Ligaments and Cartilage 9. Follow the muscles, one at a time to the joint between the upper and lower wing. Notice the shiny white tendons that connect the muscles to the joint, pull on a tendon to see how it helps the chicken move the wing. 10. Cut the tendons to remove the muscles. 11. Examine the bones of the upper part and lower part of the wing. Label the humerus, ulna, and radius bones in Figure B. Figure B humerus radius ulna 12. Observe the joints at the end of the upper wing and between the upper and lower wing. Identify the name of the joint and the type of joint in the chart below. End of the upper wing Between the upper and lower wing Joint Shoulder Elbow Type Ball and Socket Hinge 13. Look for shiny white ligaments holding bones together at the joint. Cut the ligaments so that the joint falls apart. 14. Observe the cartilage that covers the ends of bones. How is it different than the bone? Cartilage is flexible, between bones, provides a cushion so the bones to not rub on one another. Bone is hard, providing the structure and a hard brace for muscles to contract against and create movement. The bone acts as a lever in producing movement. 15. Get permission from your teacher to dispose of the chicken parts. Teachers Initials: _____ Clean Up: Dispose of chicken parts and gloves in the garbage! Wash your lab station and equipment with warm, soapy water. Dry with a paper towel. Return all equipment to the proper place. Thoroughly wash your hands with warm, soapy water. Discussion Questions: 1) Muscles are only able to pull, not push. How are complex movements possible with this limitation? Muscles work in pairs. While one contracts the other relaxes. The muscle pairs which work together are often on the opposite side of the bone allowing for one muscle to flex a joint and the other to extend a joint. 2) Explain how a wing moves using the terms muscle, bone, tendon, ligament, connective tissue, and joint. The bone acts as a lever, the pivot point is the joint, and the muscles provide the effort needed to produce movement. The tendons connect the muscles to the bone and the ligaments hold the bones together by attaching to the bone tissues on either side of the joint. The muscle contracts causing the tendon and ligaments attached associated bones and muscles causing movement in the next part of the wing. NAME: _________________ ____/9pts Making the Human Connection With your left hand grasp something with weight such as a heavy textbook and hold it at your side. Place your right hand on your upper left arm so that you can feel your muscles move. Slowly bend your left arm to raise the weight. Then slowly straighten your left arm to lower it. Repeat this motion a few times until you can feel and see what is happening. (1pts/question) 1) What joint did you use to lift the weight? elbow 2) Which muscle contracted and which muscle extended as you raised the weight. Bicep –contracts Tricep - extends 3) Which muscle contracted and which muscle extended as you lowered the weight. Bicep – extends Tricep - contracts 4) Which bone(s) in the arm moved? Ulna and radius move up as the bicep contracts 5) Which bone(s) in the arm didn’t move? Humerus Homologous structures are shared by related species and have been inherited from a common ancestor. 6) Based on the information gained from this activity, would you classify your arm and a chicken wing as homologous structures? Why or why not? Does this support your original hypothesis? (3pts) Yes, both have a humerus, ulna, and radius bone. Their bicep and tricep muscles work similarly. The bicep contracts and the tricep extends to pull the arm/wing up or in. The bicep extends and the tricep contracts to lower the arm/wing. 7) What additional information would you want to know to help you determine whether or not the human arm and chicken wing are homologous structures? (1pt) Structure of the bones and muscles in the wing tip/fingers