Chapter 19 Protists

The World of Protists—Section 1 Members of the Kingdom Protista have Membrane-bound organelles A wide variety of sizes and shapes One or many cells Many protozoans are classified according to the way they move

Protozoans are animal-like protists. Amoebas engulf food by surrounding the food with pseudopodia Pseudopodia are extension of a protozoan’s plasma membrane, which function in getting food and in locomotion.

Amoebas commonly reproduce by asexual reproduction. Asexual reproduction is when a single parent produces on or more identical offspring.

A protozoan that moves by lashing one or more of its whip-like parts (flagella) is called a flagellate Ciliates move by beating hair-like parts that cover its cell.

Cilia—locomotion (#2) Oral groove—used to eat (#6) Anal pore—extracts waste (#1)

Sporozoans produce spores which is a reproductive cell that forms without fertilization. Most sporozoans reproduce by both sexual and asexual reproduction.

Algae: Plantlike Protists—Section 2 Algae are multicellular and unicellular photosynthetic protists. Algae produce much of the oxygen on Earth.

The plant-like protists with delicate shells that make-up a large proportion of the phytoplankton in freshwater ecosystems are diatoms. *Explain how diatoms reproduce. Pg 512

The plantlike protists that are the cause of red tides are dinoflagellates. Dinoflagellates are able to spin by means of two flagella at right angles to each other. *What causes the dangerous red tides in the ocean? Pg 513

*What adaptations helps red algae to live in deep water? Pg 514 A colony is a group of cells that lives together in close association. During fragmentation an individual breaks up into pieces and each piece grows into a new individual.

During the gametophyte generation, a green algae has the haploid number of chromosomes. The gametophyte is the haploid form of the organism. The sporophyte is the diploid form of an alga that develops from a zygote and produces spores. Alternation of generations is when the life cycle of an organism has a haploid stage followed by a diploid stage.