Chapter 3: Protists

Question 1

What are the three major forms of locomotion by protists?

Answer 1

Cilia, flagella, and pseudopodia

Question 2

What are trichocysts for?

Answer 2

Protection and anchoring

Question 3

What are toxicysts for?

Answer 3

Predation and toxin release

Question 4

How do protists make locomotion happen?

Answer 4

ATP interactions of dynein arms and microtubules (similar to myosin and actin.)

Question 5

What are the forms of protist reproduction? Describe each.

Answer 5

1) Asexual reproduction:
Binary fission: splitting in two
Multiple fission: more than two
Budding: portion of the parent breaks
Encystment: a dormant/ resistant cyst
stage preceding the release of a
reproductive stage.

2) Sexual reproduction:
Conjugation: joining two nuclei to
combine genetic information. Only done
in unfavorable conditions.

Question 6

What are pseudopodia good for?

Answer 6

Breaking down/ formation of actin networks. Also aids in cytoplasmic rigidity.

Question 7

What are the three phyla under Aveolata?

Answer 7

1) Ciliophora
2) Dinozoa
3) Apicomplexa (parasites)

Question 8

Phylum Ciliophora: List important facts, if it’s a monophyletic or paraphyletic group, and details on the body plan

Answer 8

• Possess a macro and micronucleus
• Micronucleus is used for reproduction
• Metachronal beating
• Kinetosomes
• Form a monophyletic group
• Highest degree of subcellular structure

Question 9

What is metachronal beating? Where does it function?

Answer 9

Metachronal beating is a wave made by cilia for locomotion, which happens at the atomic level.

Question 10

Describe the lifestyle of Phylum Ciliophora

Answer 10

• Most are motile
• 65% are free-living (suspension feeders)
• sessile and/ or colonial
• ## 33% are symbiotic/ parasitic

Question 11

Phylum Dinozoa: List important facts, if it’s a monophyletic or paraphyletic group, and details on the body plan

Answer 11

• bear two distinct flagella
• flagella line in two grooves
• Sulcus: longitudinal flagella
• Girdle: Transverse or encircling flagella
• Dino= spin, they travel by spinning
• Produce cellulose plates around the body
• Free-living: beneficial/ harmful algae
• Some bioluminescent
• Diverse feeding (heterotrophic, mixotrophic, autotrophic)
• monophyletic

Question 12

Phylum Apicomplexa: List important facts, and determine if it’s a monophyletic or paraphyletic group

Answer 12

• Remarkable adaptations to host immunity
• Infective stages possess apical complex
• All endoparasites of animals
• Definitive and intermediate host
• paraphyletic