Chapter 21

Chapter 21

Protist and Fungi

Protists are the most diverse of all eukaryotes

• protists: eukaryotes that are not animals, plants, or fungi but show characteristics of those kingdoms.

Protist Introduction

Diversity of Protists

–Can be microscopic or can be extremely large.–Can be single celled or can be multi-

celled. –Can be autotrophic or heterotropic

Protists are broken into 3 different groups…

1. Animal Like Protists (protozoans)

• Animal like protists are heterotrophs• Eat bacteria, other protists, non-living organic

matter• Lack cell wall• Live in most aquatic environments & some in

body fluids

Protozoans are broken down into different groups by how they move.

– Zooflagellates• Use flagella to move

– Ciliates• Have cilia to move • Or feed

– Pseudopods• “false foot”• Use cytoplasm to move

Examples of Protozoans

• Paramecium:– Cilliate found in ponds

• Stentor– Ciliate that uses cilia around mouth to feed.

• Plasmodium– Protozoan that causes malaria

• Giardia– Zooflagellate that can lead to giardiasis.

Fungus Like Protists

DecomposersObtain energy from breaking down dead organic matterCell wall made of cellulose and not chitin

Examples:Slime molds

Plant Like Protists• Autotrophs– Obtain energy through

photosynthesis– All contain chloroplast

to photosynthesize

• Can be single celled– Euglena: Flagellate

that uses an eyespot to detect light. When light is not present it can become heterotrophic

Plant Like Protists

• Colonial: volvox

• Several single celled plant like protist that live and function together.

• Euglena have both characteristics of plants and animals

Fungus Kingdom

• 2nd kingdom of eukaryotes• Characterized by decomposition

Parts of a fungi

• Reproductive Structure– Part above ground that is

seen.– Used to characterize the

fungus• Hyphae

– Cytoplasmic threads with chitin cell walls

• Mycelium– Mat of hyphae

underground

• Mycelium carry out the decomposition process.

• Absorptive nutrition– Mycelium release

enzymes to break down material and then absorbs the digested material

How do Fungi Reproduce?

• Spores:– Released into the air or water to allow fungi to

reproduce asexually

– Able to withstand harsh, dry environmental conditions.

Types of Fungi

• Club fungi– Typical mushrooms

• Mold• Yeast– Imperfect fungi– Only reproduce asexually

Roles of Fungus

• Help with decomposition and adding nutrients to soil.

• LICHEN– Fungus and algae – 1st to grow on rocks and help to create soil

• Mycorrhizae– Fungus increases the surface area of plant roots

• Food– Cheese, bread, beer

Roles of Fungi

• Disease– Athletes foot– yeast infections– dutch elm disease– chytrid fungus.