Protists

Question 1

Key Facts on Protists

Answer 1

• Eukaryotic
• Heterotrophic or autotrophic
• reproduce sexually or asexually
• Live in aquatic or other moist environments

Question 2

Importance of Protists

Answer 2

-Protists play key roles in aquatic ecosystems.
-Some protists can perform photosynthesis
-Non-photosynthetic protists are consumers
-Many protists are parasites – they live in, or on, other organisms
-Most parasites do not harm their host organism, but some cause serious disease:
malaria
sleeping sickness
amoebic dysentery
beaver fever (causes diarrhea, abdominal pain, weight loss, blood in stool)

Question 3

Origin

Answer 3

• Protists were the first eukaryotes

- These internal membranes likely developed from the folded cell membrane of an ancestral prokaryotic cell.

Question 4

Origin Chloroplasts & Mitochondria

Answer 4

Present-day mitochondria and chloroplasts each have two membranes

Their inner membranes are similar to those of their ancestral prokaryote, while their outer membranes match the cell membranes of the eukaryotes

Question 5

Life Cycle

Answer 5

-Protists reproduce sexually and asexually
-Single Cell Protists
Asexually-Binary fission
Sexually-Conjugation
-Multicellular Protists
Sexually-Sex cells (ie male sperm and female eggs)