BIOL 117: Module 6 Part 2

Are protists prokaryotic or eukaryotic organisms?

Eukaryotic.

Do we consider the phylogeny of protists to be monophyletic or paraphyletic?

Paraphyletic.

Are protists unicellular, multicellular, or are both present in this group?

Unicellular and multicelluar are present.

How do we explain the morphological innovation of the nuclear membrane and endomembrane organelles?

An early eukaryote may have engulfed a smaller eukaryote, using its vacuole as a cell wall; the organelles of the engulfed cell folded to create a nuclear membrane.

How do we explain the morphological innovation of the mitochondria and chloroplasts?

Predatory protists swallowed aerobic bacteria (mitochondria) and photosynthetic protists (chloroplasts).

Which group of protists are obligate parasites?

Alveolates.

What species of the alveolates did we discuss?

Apicomplexans.

What diseases do apicomplexans cause?

Malaria and toxoplasmosis.

Which group of protists gets continually smaller until sexual reproduction?

Ditaoms.

Why do diatoms get smaller until sexual reproduction?

There are problems when reproducing, inside the shell can divide easily but outside cannot divide.

What causes red tide and why is it dangerous?

Dionflagellates (algal blooms).

Are plamodial slime molds considered multicellular or unicellular living in a colony?

Plasmoidal slime colds are unicellular.

Are cellular slime molds considered multicellular or unicellular living in a colony?

Cellular slime molds start as unicellular then become multicellular.

Are brown algae considered multicellular or unicellular living in a colony?

Brown algae are multicellular.

What substance is used to create the cell wall for dinoflagellates?

Cellulose plate armor.

What substance is used to create the cell wall for diatoms?

Silica.

Protists are definitely diverse, but why do we say that “Protists do not have one defining characteristic that separates them from all other eukaryotic organisms?”

There is no same characteristic shared between every protist in order for them to be defined by that characteristic only.