Animal Reproduction Interactivity

Can you describe how an aquarium moon jellyfish population will change over time?

Record Data and Observations

Part 1 Explore the Life Cycle

For each transition in the jellyfish life cycle, indicate whether it is the result of growth, sexual reproduction, or asexual reproduction. Provide the evidence that supports your choice for each.

Adult medusas to larvae

Larva to polyp

Polyp to reproducing polyp

Reproducing polyp to juvenile medusas

Juvenile medusas to adult medusas

Analyze and Conclude

1. Draw Conclusions Once polyps have been established and are producing juvenile medusas, is sexual reproduction required to provide adult medusas for the exhibit? Explain why or why not.

2. Scientific Writing The museum has asked you to make a sign for the exhibit. Visitors will read the sign when guides and volunteers are not available to talk about the exhibit. Using the information gathered in this interactivity, write a paragraph that describes what visitors may see in the tank and explains the reproductive cycle of jellyfish.

Jellyfish do not give birth to their young because they expel undeveloped eggs in the form of zygote or embryo from their bodies and deposit them on the ocean floor before moving on. They don't even care about the eggs that have been laid.

Step 2

Jellyfish have two distinct body types during their lives: medusa and polyps. Polyps reproduce by budding while medusa reproduce as by spawning eggs and sperm.

Jellyfish can reproduce in the adult, or medusa, stage by releasing sperm and eggs into the water, forming a planula. Polyps clone themselves and bud, or strobilate, into ephyra, a different stage of jellyfish life. The adult medusa jellyfish develops from his form.

Only a few jellyfish species obtain sperm through their mouths in order to fertilise eggs within their bodies, but the majority of jellyfish simply release sperm or eggs into the water. They will do this once a day, normally at dawn or dusk, if conditions are favorable.