Category 1: Protist Basics (21.1)
Protists are best described as ________ that are not plants, animals, or fungi.
What are eukaryotes?
Name the three main types of protist movement.
What are flagella, cilia, and pseudopodia?
What are plant-like protists that make their own food called?
What are algae?
Fungi are heterotrophs with cell walls made of ________.
What is chitin?
Which group includes Amoeba, Paramecium, and Euglena?
What are protists?
How are lichens able to survive in places that most other organisms are unable to live, such as on
mountaintops and in barren deserts?
Lichens can survive on mountaintops, bare rock, and in deserts because they are a mutualistic partnership between a fungus and an alga or cyanobacterium.
The fungus protects the photosynthetic partner from drying out and provides structure.
The alga/cyanobacterium makes food through photosynthesis.
This relationship allows lichens to live where few nutrients or moisture are available and to begin forming soil on bare surfaces.
Why is the old “Kingdom Protista” no longer used by scientists?
What is protists are too diverse and resemble other kingdoms?
Paramecium uses this process to exchange genetic material.
What is conjugation?
Name one ecological role of photosynthetic protists.
What is they produce oxygen and are the base of aquatic food chains?
What is the underground network of filaments called?
What is the mycelium?
How are fungi different from plants?
What is fungi are heterotrophic and absorb food, plants make food?
List two diseases that are spread by insects and caused by protists, and name the protist that causes
each disease.
Malaria – caused by the protist Plasmodium; spread by the Anopheles mosquito.
African Sleeping Sickness – caused by the protist Trypanosoma; spread by the tsetse fly.
Which theory explains how mitochondria and chloroplasts evolved?
What is the Endosymbiotic Theory?
What is the internal structure used by Amoeba to digest food?
What is a food vacuole?
What causes an algal bloom?
What is extra nitrogen from fertilizer runoff?
Name one way fungi help ecosystems.
What is decomposing dead organisms?
Both protists and fungi can reproduce asexually by producing ________.
What are spores?
A group of scientists concludes that protists should be organized into several different kingdoms.
Evaluate their conclusion. Use evidence to support your argument.
Scientists are correct to split “protists” into several kingdoms (or abandon a single Kingdom Protista altogether) because the group is not monophyletic—it doesn’t include all descendants of a common ancestor. Molecular phylogenetics (DNA/RNA comparisons) shows so-called protists fall into multiple major eukaryotic lineages (e.g., Archaeplastidawith red/green algae and plants; SAR clade including diatoms and dinoflagellates; Excavata like euglenoids; Amoebozoa; and Opisthokonta, the lineage that also includes fungi and animals). These lineages differ in ultrastructure (e.g., types/arrangements of flagella and microtubules), organelle origins (primary vs. secondary/tertiary endosymbiosis of chloroplasts), mitochondrial forms (or losses), cell coverings (pellicles, tests, varied wall chemistries), and life cycles (asexual fission, conjugation, alternation of generations). Because many protists are more closely related to plants, animals, or fungi than to other protists, a single kingdom hides real evolutionary relationships. Organizing them into several kingdoms (or modern “supergroups”) better reflects common ancestry and helps make predictions about traits, ecology, and disease.
What key cell feature makes protists different from bacteria?
What is a nucleus (and membrane-bound organelles)
When a protist reproduces asexually, what process is used?
What is mitosis?
Which parasitic protist causes malaria and how is it spread?
What is Plasmodium, spread by the Anopheles mosquito?
What type of symbiotic relationship do mycorrhizae form with plants?
What is mutualism?
What do algae and fungi have in common?
What is they can form symbiotic relationships like lichens?
Explain how both protists and fungi maintain balance (homeostasis) in ecosystems.
Protists produce oxygen and form the base of food chains, while fungi recycle nutrients by decomposing waste and dead organisms. Both keep ecosystems balanced and support other life forms.
Name one way protists are more like plants and one way they’re more like animals.
What is photosynthesis (plants) and movement/feeding (animals)
What advantage does sexual reproduction provide compared to asexual reproduction?
What is genetic variation?
Name two mutualistic protist relationships.
What are zooxanthellae with coral and Trichonympha in termites?
List the four main groups of fungi.
What are Basidiomycota, Ascomycota, Zygomycota, and Chytridiomycota?
Why are fungi considered more closely related to animals than plants?
What is they are both heterotrophs with chitin (or similar molecules)?
Identify and briefly explain the process by which paramecia exchange genetic material between
individuals.
The process is called conjugation.
During conjugation, two Paramecia come together side by side and form a cytoplasmic bridge. Each cell’s micronucleusundergoes meiosis, producing haploid nuclei. The cells then exchange one haploid micronucleus with each other. These exchanged nuclei fuse with the remaining micronucleus in each cell to form a new diploid micronucleus.
Although conjugation does not create new cells, it increases genetic variation, which helps the population adapt to changing environments.