Structures of Life Crayfish FOSS Structures of Life, TESLA Science Notebooks

BIG IDEA: All living organisms have identifiable structures and characteristics that serve different functions in growth, survival, and reproduction.

Guiding Questions What are the structures of crayfish? What does a crayfish need to survive? What are observable crayfish behaviors?

What are some of the interesting parts that you notice on your crayfish? Parts of the crayfish are their structures. Just like the parts of the plants and seeds are called structures. We are going to keep a list of the structures that we observe in our science notebooks. Part I: Structures

Some of you were able to notice differences in your crayfish. They were not all the same. Some of these differences may be due to age or handicapping… Loss of an antennae or leg. What else could cause noticeable differences in our crayfish? Gender: Male and female crayfish will have different structures We can compare what we saw with our crayfish diagram and identify these different structures. Can you predict the gender of your crayfish? Part I: Structures

Female Crayfish Male Crayfish 1.Long antennae 2.Short antenna 3.Pincer 4.Eye 5.Mouth 6.Walking leg 7.Carapace 8.Short swimmeret 9.Modified swimmeret 10.Egg pore 11.Long swimmeret 10

How can you tell the difference between a male and female crayfish? Part I: Structures Male CrayfishFemale Crayfish First pair of swimmerets is modified Bigger pincersSmaller pincers Narrower taiIsWider tails No egg poresEgg pores Shorter swimmeretsLonger swimmerets

What do we need to know about crayfish in order to keep them in our classroom? Most living organisms require a certain amount of: Food… What will they eat, how much, how often? Water… How deep, what temperature, how clean? Shelter… Do they need hiding places or rocks? Air… How will they get air to breath? Space… Should they live together? Part II: Habitat

The place where an animal lives is called a habitat. In our classroom the crayfishes habitat will be these large tubs. Part II: Habitat Habitat Natural HabitatClassroom Habitat In their natural habitat, crayfish find their own food and shelter. In our classroom, they must be fed and given a safe place to live.

Part II: Habitat Classroom Habitat It will be your groups responsibility to care for the crayfish habitat and make observations. Our crayfish will eat elodea, blood worms, romaine, cat food The plastic cups are crayfish shelter Draw and Label your Habitat

Part III: Behaviors Crayfish Shelters What did you learn from your investigation about crayfish behaviors and their use of shelters? Do crayfish like to share their shelter with other crayfish? Will they defend their shelter or place in their habitat? Crayfish are territorial creatures. They will claim a location in their habitat and defend it against others. The biggest or strongest crayfish will normally claim the territory of its choice. How do you Know?

Molting is the process by which crayfish shed their outer shells in order to grow. A crayfish’s skeleton is on the outside of its body. It protects the crayfish from predators and other dangers. The crayfish has to shed its too-small shell to grow. The problem with this is it leaves the crayfish vulnerable until the new exoskeleton forms. A crayfish can also grow a new leg or claw if the old one breaks off. What is one advantage and one disadvantage of molting?

Beetle Structures

Beetle Habitat