Colloblasts (Comb Jelly Glue Cells)

Glue on a spring

Comb jellies are see-through ocean animals. They look a bit like jellyfish, but they are a different group. They swim by beating rows of tiny hairs called combs. When light hits the combs, they shimmer with rainbow colors!

Many comb jellies have two long tentacles. The tentacles are covered with colloblasts. Each colloblast has:

• A round head covered in sticky glue bumps.
• A straight stalk holding it to the tentacle.
• A spiral thread wound around the stalk, like a spring.

Sticky fishing lines

A comb jelly spreads out its tentacles like fishing lines. When a tiny animal bumps into a colloblast, the glue bumps burst and stick to it.

If the little animal tries to swim away, the spiral thread stretches like a spring, so it can't pull free. Then the comb jelly pulls its tentacle in and moves the food to its mouth.

Colloblast quiz