General Biology II Chapter 21 Flashcards
(28 cards)
Fill in the Blank:
“Eukaryotes that are not fungi, plants, or animals are collectively referred to as the ________. ________ include the oldest eukaryotic lineages.”
Protists.
True or False?
“The vast majority of protists are free-living single cells.”
True.
True or False?
“Protists which are free-living single cells play important ecological roles as producers in aquatic habitats and as tiny predator on microorganisms.”
True
What is a valid biological group called?
A clade.
True or False?
“Protists constitute a valid biological group (a clade) and many shared traits defines them.”
False. “Protists do not constitute a valid biological group (a clade) and no shared trait defines them.”
True or False?
“Some protists are more closely related to plants, fungi, or animal than to other protists.”
True.
What organism consists of cells that live together but remain self-sufficient? Each cell retains the traits required to survive and reproduce on its own.
A colonial organism.
Cells of which of which organism have a division of labor and are independent? In such organisms, only specialized cells produce gametes.
Multicellular organism.
True or False?
“Protists are eukaryotes, so they all have a nucleus.”
True.
What consists of a plasma membrane and a thin layer of elastic proteins just under it? It constrains the cell’s shape somewhat, but flexes enough to allow the organism to bend and to squeeze through narrow openings.
A pellicle.
What are organelles that collect excess water from the cytoplasm then contract and expel it from the cell through a pore?
Contractile vacuoles.
True or False?
“Protists do not have chloroplasts.”
False. “Many protists have chloroplasts.”
By which process is cyanobacteria evolved into chloroplasts in the common ancestor of red algae and green algae? These chloroplasts have two membranes.
Primary endosymbiosis.
By which process are green algae and red algae evolved into chloroplasts in other protists? These chloroplasts have four membranes.
Secondary symbiosis.
What is the pigmented organelle that allows some motile photosynthetic protists to detect light so they can move toward areas that are best for photosynthesis?
An eyespot.
True or False?
“Most protists are obligate aerobes, meaning they need oxygen to live.”
True.
True or False?
“Most anaerobic protists lack a mitochondria.”
False. “Most anaerobic protists have modified mitochondria.”
True or False?
“Protists include autotrophs and heterotrophs.”
True.
Fill in the Blank:
“__________, such as the algae, carry out photosynthesis by the same oxygen-producing pathway as cyanobacteria.”
Autotrophs.
Fill in the Blank:
“_____________ protists absorb organic molecules directly from their environment or capture and ingest smaller organisms such as bacteria.”
Heterotrophic.
Fill in the Blank:
“A few protists are __________; they can be photosynthetic or heterotrophic depending on conditions.”
Mixotrophs.
True or False?
“The overwhelming majority of protists are free-living and aquatic, living in seawater or freshwater habitats.”
True.
What is the collective term for the tiny drifting and swimming organisms in lakes and seas?
Plankton.
Which type of plankton includes all the photosynthetic organisms?
Phytoplankton.
