Protists

Question 1

Are protists monophyletic or paraphyletic?

Answer 1

Paraphyletic

Question 2

What is the difference between Eukaryotes and Prokaryotes and what are protists classified under?

Answer 2

Protists are eukaryotes and have compartmentalization of nucleus and organelles (membrane bound organelles)

Question 3

How did organelles form in protists?

Answer 3

Prokaryotic cell membrane folded in on itself which caused formation of endoplasmic reticulum (which happened due to a mutation)

Question 4

What is endosymbiosis and which organelles were effected by this?

Answer 4

• Engulfing of other organelles

- Mitochondria and Chloroplasts were engulfed because they were originally individual cells

Question 5

When brown algae engulfed red algae, which already had chloroplasts, what is this called?

Answer 5

Secondary endosymbiosis

Question 6

Are protists unicellular or multicellular and which is more beneficial?

Answer 6

• Protists are both

- Multicellularity is more beneficial

Question 7

What are the three taxa in the supergroup Excavata?

Answer 7

Diplomonads, parabasalids, and euglenozoans

Question 8

Describe Diplomonads?

Answer 8

• Unicellular
• Move with flagella
• Have 2 nuclei
• Have degenerate mitochondria (ancestors had mitochondria and now it doesn’t function correctly/may not have one at all)
• Giardia: most common intestinal parasite in the U.S.

Question 9

Describe Parabasalids?

Answer 9

• Live in termite guts
• Undulating membrane for locomotion
• Use flagella
• Lack mitochondria which is a derived trait

Question 10

Describe Euglenozoa?

Answer 10

• Earliest eukaryotes to possess mitochondria
• Some have chloroplasts but may become heterotrophic in dark
• Others strictly heterotrophic (may be parasitic)
• Asexual reproduction only
• Contractile vacuoles: collect excess water
• African Sleeping Sickness

Question 11

What taxa are in supergroup Chromalveolata?

Answer 11

• Dinoflagellates
• Apicomplexans
• Ciliates
• Brown Algae
• Oomcyetes

Question 12

Describe Dinoflagellates?

Answer 12

• Photosynthetic and unicellular
• Move with flagella
• Live in aquatic environments
• Some are bioluminescent
• “Red tides” are blooms: can cause deaths

Question 13

Describe Apicomplexans?

Answer 13

• Spore forming animal parasites
• Plasmodium causes malaria
• Toxoplasma gondii: causes reckless behavior
• Causes infections in humans with immunosuppression

Question 14

Describe Ciliates?

Answer 14

• Feature large number of cilia arranged in longitudinal rows or spirals around the cell
• Pellicle: tough but flexible outer covering
• 2 types of nuclei: Micronucleus (without will reproduce asexually) and Macronucleus (essential for function)
• 2 types of vacuoles: Food vacuoles (digestion of food) and Contractile vacuoles (regulation of water balance)

Question 15

Describe Brown Algae?

Answer 15

• Not plants
• Diatoms: unicellular, unique double shells made of silica
• Conspicuous seaweed

Question 16

Describe Oomcyetes?

Answer 16

• Caused potato famine
• Can be aquatic or terrestrial
• Pathogens (make things sick) or saprobes (feed on dead things)

Question 17

What taxa is in supergroup Opisthokonta?

Answer 17

-Choanoflagellida

Question 18

Describe choanoflagellida?

Answer 18

• Most like common ancestors of animals
• Single flagella, surrounded by funnel shaped collar (structure matched in sponges)
• Use collar to feed on bacteria

Question 19

Is Amoebozoa a taxa or supergroup?

Answer 19

Both

Question 20

Describe Amoebozoa?

Answer 20

• Move by pseudopods
• Slime molds (not related to fungi): single celled, multinucleate, oozing masses and single cells combine
• Causes amoebic dysentary

Question 21

What taxa are in supergroup Rhizaria?

Answer 21

• Foraminifera
• Radiolara
• Cercozoa

Question 22

Describe Foraminifera?

Answer 22

• Pore studded shells called tests, through which thin podia emerge (podia used for swimming and eating)
• Produce limestone with tests

Question 23

Describe Radiolara?

Answer 23

• Produce intricate mineral skeletons

- Needle like pseudopods

Question 24

Describe Cercozoa?

Answer 24

• Mostly heterotrophic
• Abundant in soil and in all freshwater and marine habitats
• Many have filapodia
• May be most abundance predator but have no mouth

Question 25

What taxa is in the supergroup Archaeplastida?

Answer 25

Rhodophyta

Question 26

Describe Rhodophyta?

Answer 26

- Red algae range in size - Have accessory photosynthetic pigments other than chlorophyll - Red

Question 27

What are the two monophyletic groups that make up Green Algae?

Answer 27

- Chlorophyta | - Charophyta (most closely related to plants)

Question 28

Describe Chlorophytes?

Answer 28

- Many lines of specialization derived from chlorophytes - Cell specialization in colonial chlorophytes - Haploidiplontic live cycles in multicellular chorophytes

Question 29

What is haploidiplontic?

Answer 29

There are stages of life that are haploid and stages that are diploid. All plants are haploidiplontic. The gametophyte generation makes the sex cells.

Question 30

Describe the haploidiplontic life cycle.

Answer 30

-Starts with multicellular diploid stage (sporophyte) This produces haploid spores by meiosis The diploid spore mother cells (sporocytes) undergo meiosis in sporangia This makes four haploid spores and these are the first cells of the gametophyte generation -Then the multicellular haploid stage (gametophyte) Spores divide by mitosis This produce gametes through mitosis Gametes fuse to form diploid zygote

Question 31

What is the difference between Charophytes and Chlorophytes? Which came first and where do land plants fall in this order?

Answer 31

- Charophytes have phylogenetic relationship to land plants | - Chlorophytes came first, then charophytes, then land plants