What are Cnidarians?

Invertebrate animals that use stinging cells to capture food and

defend themselves.

Cnidarians Body Structures

Polyp - vaselike shape and usually adapted for a life attached

to an underwater surface.Medusa - a bowl shape and

adapted for a free-swimming life.

How cnidarians obtain food?

A stinging cell containing a thread with spines is shot into prey. Some spines contain venom.

When prey is helpless, cnidarians use tentacles to pull prey into

their mouths.

Anemone eating

http://www.youtube.com/watch?v=ctqvqES1PE8&feature=related

http://www.youtube.com/watch?v=o1A5acWEERA&feature=related

Clown fish and anemone

http://www.youtube.com/watch?v=NtfQ3aIBpGY&feature=related

http://www.youtube.com/watch?v=I089Tw7Fk_A&feature=related

How do cnidarians move?

A nerve network, not nervous system, conducts signals from sensory cells to muscle cells allowing them to respond to

danger and prey.

How do cnidarians move?

Video

How do cnidarians move?

video

How do cnidarians reproduce?

Sexual – Some species have both sexes, some are male and female.

Asexual – Polyps are asexual, some bud similarly to sponges

some pull apart.

How do cnidarians reproduce?

video

Reproduction

http://www.youtube.com/watch?v=u8LGZaezpV8&feature=related

Medusa life cycle