Planaria (a flatworm)

Polycelis felina

DescriptionP. felina• are nonparasitic. They do

not suck blood like leeches.

• are about 1 centimeter long.

• avoid light

DescriptionP. felina• are flat with heads shaped

like an arrow point.

• move by twisting, turning, stretching, and contracting its body.

FoodP. falina are carnivores.

• They eat decaying meat,

• insects,

• and larvae.

Method of FeedingP. falina• have a feeding tube in the

middle of its ventral side.• secrete digestive enzymes

from a single feeding tube to begin external digestion.

• suck up food through its feeding tube.

• eliminate waste through the same tube it eats with.

DigestionP. falina• have three germ

layers and a single digestive cavity.

• have branched intestines throughout the body

Planarian Traps

Habitat• Some planarians live in

saltwater.

• Some live in fresh water.

• Some live under logs and in the soil.

AdaptationsP. felina • secretes a slimy mucus.

• has cilia on its belly that help it glide on a film of mucus.

AdaptationsP. falina • have two eye spots that cannot see objects, but

only detect the brightness of light.

AdaptationsP. falina • Take in oxygen and release carbon dioxide by

diffusion through its skin.

O2 CO2

AdaptationsP. felina • can regrow lost body

parts.

• if cut in half, can regrow each half into two separate individuals.

Video(Planarian Regeneration and stem cells)

BibliographySlide 1: http://www.uniprot.org/taxonomy/6162

Slides 2-4: https://www.ebiomedia.com/the-biology-classics-planaria-feeding.html

Slides 3-7: http://en.wikipedia.org/wiki/Planarian

Slides 8-9: http://raven.islandwood.org/kids/stream_health/macros/Planaria.html

Slide 10-12: http://gardener.wikia.com/wiki/Planaria

Slide 13: http://mcb.illinois.edu/news/feature/270/ Video: http://www.hhmi.org/biointeractive/planarian-

regeneration-and-stem-cells