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Slide 2 / 22 4th Grade Bite into Structure and Function Activity 2015-08-27 www.njctl.org
Slide 3 / 22 Animal Teeth Animal teeth are a good example of how structure fits function. Below is a cast of human teeth. There are three different types of teeth. Can you identify them? Click on the picture to see the answer. Incisors Canine Canine Molars Molars Source: Wikimedia Commons. Author: Stotan.
Slide 4 / 22 Incisors Different animals have different amounts and types of incisors. Humans have 8 (four on top and four on bottom). Incisors Think about your incisors. What do you use them for? How does their structure fit their function? Source: Wikimedia Commons. Author: Stotan.
Slide 5 / 22 Canines Canines also come in many shapes and sizes. Humans have 4 canines - two on top and two on bottom. Canine Canine Source: Wikimedia Commons. Author: Stotan. Think about your canines. What do you use them for? How does their structure fit their function?
Slide 6 / 22 Molars The number of molars present in animals varies greatly. How many do you have? Molars Molars Source: Wikimedia Commons. Author: Stotan. Think about your molars. What do you use them for? How does their structure fit their function?
Slide 7 / 22 What does this animal eat? You can often determine the type of food an animal eats based on its teeth. Look at the skull below. What types of teeth do you see? Make a hypothesis about what the animal eats. Click to the next slide to see the answer. Source: Wikimedia Commons. Author: Vassil.
Slide 8 / 22 What does this animal eat? This is a sheep. It has incisors at the front and molars at the back. The sheep eats plants. It uses its incisors to bite the plants and its molars to chew the plants. Molars Incisors Source: Wikimedia Commons. Author: Vassil. Most herbivores (plant eaters) have incisors and molars. Why don't sheep have any canines?
Slide 9 / 22 What does this animal eat? Try this one. Look at the teeth and make a hypothesis about the type of food that this animal eats. Click to the next slide for the answer. Source: Wikipedia. Author: BS Thurner Hof.
Slide 10 / 22 What does this animal eat? This is the skull from an orca (killer whale). Orcas eat other fish and marine mammals. They have canines to tear apart their food. They do not have incisors or molars because they do not bite or chew their food. Incisors Source: Wikipedia. Author: BS Thurner Hof. Most carnivores (meat eaters) have large incisors to tear meat.
Slide 11 / 22 What does this animal eat? How about this skull? What type of food do you think this animal eats? Source: Wikipedia. Author: Thedemonhog.
Slide 12 / 22 What does this animal eat? This is the skull from a grizzly bear. Grizzlies eat many different things: grass, berries, fish and other animals. They use their incisors to bite plants, canines to tear meat and molars to chew their food. Incisors Molars Canines Source: Wikipedia. Author: Thedemonhog. Many omnivores (eat both plants and animals) have a similar arrangement of teeth.
Slide 13 / 22 Tooth Challenge Now that you understand the different functions of teeth, you are ready for the Tooth Challenge! Organize into small groups. The following slides have pictures of unusual teeth. Discuss different ideas with your group and then submit your hypothesis for what the animal eats and/or how it uses its teeth. Remember: Look at the structure of the teeth. Structure fits function! The tusks of this walrus are actually its canine teeth! Source: Wikimedia Commons. Author: Hickey.
Slide 14 / 22 Tooth Challenge #1 Source: Dinopedia. Author: Dino-might1337. 1. Discuss with your group. Write down your final hypothesis on your activity worksheet. 2. All groups will share their hypothesis with the class. 3. As a class, discuss the merits of each hypothesis.
Slide 15 / 22 Tooth Challenge #2 Source: Wikimedia Commons. Author: NOAA Fisheries Service. 1. Discuss with your group. Write down your final hypothesis on your activity worksheet. 2. All groups will share their hypothesis with the class. 3. As a class, discuss the merits of each hypothesis.
Slide 16 / 22 Tooth Challenge #3 Source: YouTube. Author: World 5 List. 1. Discuss with your group. Write down your final hypothesis on your activity worksheet. 2. All groups will share their hypothesis with the class. 3. As a class, discuss the merits of each hypothesis.
Slide 17 / 22 Tooth Challenge Answers
Slide 18 / 22 Answer: Tooth Challenge #1 This is the helicoprion, a shark that went extinct 230 million years ago. Source: Dinopedia. Author: Dino-might1337. There are a few different hypotheses about how the shark used these teeth. Some think that it would swim into a school of fish and fling out the lower jaw to catch fish. Others think that the teeth were used to break into the hard shells of certain prey.
Slide 19 / 22 Answer: Tooth Challenge #2 This is baleen from a baleen whale. Source: Wikimedia Commons. Author: NOAA Fisheries Service. Source: Wikipedia. Author: Kurzon. Baleen is made from the same material as our hair and nails. The baleen whale takes in a huge mouthful of water, then pushes the water out through the baleen. The baleen acts as a filter, with only small animals (such as krill) remaining in the mouth as food.
Slide 20 / 22 Answer: Tooth Challenge #3 This is a leatherback sea turtle. Source: YouTube. Author: World 5 List. Source: Wikimedia Commons. Author: U.S. Fish and Wildlife Service Southeast Region. The leatherback sea turtle is the largest of all turtles. These turtles only eat one thing: jellyfish. Jellyfish are very slimy and slippery. The jagged, backwards facing teeth ensure that the jellyfish efficiently move into the turtle's stomach.
Slide 21 / 22 Works Cited
Slide 22 / 22 BS Thurner Hof 2005, Orca-Schadel.jpg, photograph, viewed on 15 July 2015, <https://en.wikipedia.org/wiki/file:orca-sch%c3%a4del.jpg>. Dino-Might1337 2015, Helicoprion1337.jpg, image, viewed on 15 July 2015, <http://dinopedia.wikia.com/wiki/file:helicoprion1337.jpg>. Hickey, Bill 2008, Walrus.jpeg, photograph, viewed on 15 July 2015, <https://commons.wikimedia.org/wiki/file:walrus.jpeg>. Kurzon 2013, Humpback Whale underwater shot.jpg, photograph, viewed on 15 July 2015, <https://en.wikipedia.org/wiki/file:humpback_whale_underwater_shot.jpg>. NOAA Fisheries Service 2004, Baleen.jpg, photograph, viewed on 15 July 2015, <https://commons.wikimedia.org/wiki/file:baleen.jpg>. Stotan 2006, Upper Jaw Dentition.jpeg, photograph, viewed on 15 July 2015, <https://commons.wikimedia.org/wiki/file:upper_jaw_dentition.jpeg>. Thedemonhog 2008, Grizzly skull.jpg, photograph, viewed on 15 July 2015, <https://en.wikipedia.org/wiki/file:grizzly_skull.jpg>. U.S. Fish and Wildlife Service Southeast Region 2011, Leatherback sea turtle Tinglar, USVI (5839996547).jpg, photograph, viewed on 15 July 2015, <https://commons.wikimedia.org/wiki/file:leatherback_sea_turtle_tinglar,_usvi_(5839996547).jpg>. Vassil 2007, Crane mouton.jpg, photograph, viewed on 15 July 2015, <https://commons.wikimedia.org/wiki/file:cr%c3%a2ne_mouton.jpg>. World 5 List 2014, Top 5 Animals With Incredible Teeth, video, viewed on 15 July 2015, <https://www.youtube.com/watch?v=h0p3fe9boyc>.