Steven Yeh

Pd. 4

What Are They?

• 2 groups of protists– 1. Plasmodial slime molds– 2. Cellular Slime Molds

• Similar to fungi because of convergent evolution of filamentous body structure– Use spores to reproduce and spread to get

food like fungi– Decomposers like fungi

Plasmodial Slime Molds

• Brightly pigmented (yellow or orange)• All heterotrophic• Feeding stage is called plasmodium (amoeboid

mass)– Diameter of several centimeters at largest

– Diploid

– Single mass of cytoplasm undivided by membranes and have lots of nuclei

– Used to study details of mitosis

– Cytoplasm streams back and forth in pulsing flows called cytoplasmic streaming; helps distribute nutrients and oxygen

– Eats by phagocytosis by extending pseudopodia through soil/leaf mulch/logs.

Life Cycle of Plasmodial Slime Mold

Cellular Slime Molds

• Feeding stage: solitary cells that function individually– When out of food, it then functions like a unit

• Cells maintain identity and are separated by membranes

• Haploid (only zygote is diploid)• Fruiting bodies used in asexual

reproduction• No flagellated stages

Life Cycle of Cellular Slime Mold

Pictures of Slime Molds – Fuligo Septica

Myxomycetes and Lamproderma

Protostalids