Download Protist PowerPoint Notes

Biologist ___________________________
Date ______________
Protist PowerPoint
The First Eukaryotes
Protists are ___________ that are not members of the plant, animal, or fungi kingdoms.
Although most protists are ___________, quite a few are not.
The “Protist” Dilemma
Biologists have discovered that “protists” display a far greater degree of ___________
than any other eukaryotic kingdom.
___________, brown algae, diatoms, and slime molds are examples of protists.
Biologists also found that many “protists” are far more closely related to members of
___________ eukaryotic kingdoms than they are to other “protists.”
What “Protist” Means Today
Even though the biologist building the Tree of Life prefer a ___________
classification, the word “protist” remains in common usage, even among scientists.
Bear in mind that “protists” are not a single kingdom but a ___________ of organisms
that includes several distinct clades.
Protists—Ancestors and Descendants
The split between Archaea and Eukarya may have come as early as ___________ years
ago. Since that time, protists have diversified into as many as 300,000 species.
The roots of all eukaryotic diversity, from plants to animals, are found among the
___________ of protists.
Amoeboid Movement
Many unicellular protists move by changing their shape, a process that makes use of
cytoplasmic projections known as ___________.
Amoeboid movement is powered by a cytoskeletal protein called ___________. Actin
also plays a role in the muscle contractions of animals.
Cilia and Flagella
Many protists move by means of cilia and flagella, structures supported by
___________. ___________ are short and numerous, and they move somewhat like oars on a
boat.
___________ are relatively long and usually number only one or two per cell. Some
flagella spin like tiny propellers, but most produce a wavelike motion from base to tip.
Passive Movement
Some protists are ___________ —they depend on air or water currents and other
organisms to carry them around.
These protists form reproductive cells called ___________ that can enter the cells of
other organisms and live as parasites.
Conjugation
Paramecia and most ciliates reproduce asexually by ___________ cell division.
However, under stress, paramecia can remake themselves through conjugation—a
process in which two organisms ___________ genetic material.
Paramecium has ______types of nuclei: a macronucleus and one or more smaller
micronuclei.
The ___________ holds a “reserve copy” of every gene in the cell.
The ___________ has multiple copies of the genes the cell uses in its day-to-day
activities.
Sexual Reproduction
Many protists have complex sexual life cycles in which they alternate between a
diploid and a haploid phase, a process known as alternation of ___________.
Water molds reproduce asexually by producing spores in a structure called a
___________.
The male and female structures produce haploid nuclei that fuse during ___________,
forming a zygote that begins a new life cycle.