Protists Pt 2

Question 1

The Foraminifera

Definition, where are they found, why are they important

Answer 1

Single celled organisms with calcium carbonate shells
- most live in the ocean, 40 species float in the water, the rest live anywhere else
- Paleontologists are able to use their fossils to decipher changes in the Earth’s climate

Question 2

Euglenids

Definition, what are some examples

Answer 2

1/3 photsynthetic and important food source in fresh water food chains
Tyrpanosoma cruzi causes Chagas disease (infects people through insects)
Trichonyma: lives in termites guts to help them digest wood

Question 3

Apicomplexans

Answer 3

Parisitic single celled eukaryotes that are moved by flection
Most important one is called Plasmodium Falcipurum which causes malaria (life cycle of malaria included Plasmodium proliferation)

Question 4

Dinoflagalletes

How many living species are there? Importance to the food chain

Answer 4

Mostly unicellular algae with roughly half of them being autotrophs
-4000 different living species
- covered by hard shells made of cellulose and silicate
- Serve as a food source for a broad array of fish and other animals in marine/fresh water

Question 5

What happens when a specific species of dinoflagallete proliferates like crazy?

Answer 5

A red tide can ensue. A toxic substance is produced and the death toll on other species living around can be very high

Question 6

Algae

Answer 6

Plant like protists as they are mostly autotrophic, multicellular, aquatic organisms
- Responsible for fixing half of the worlds carbon and liberating oxygen

Question 7

What are the three types of algae/definition

Answer 7

Brown alagae- ie. kelp and can be used for potash (gun powder) and emulsifiers (ice cream, gelatin, lotion)
Green algae- similarities to plants, such as clorophyll and other sun trapping molecules in photosynthesis and their cell walls, can be multi/uni cellular and primarily found in fresh water environments
Red algae

Question 8

What is a main difference between protists and bacteria/archaea

Answer 8

Some protists are fairly complex multicellular organisms (brown algae ie.) ALSO multicellularity evolved on two different occasions

Question 9

What makes brown/ green/red algae different

Answer 9

Brown algae contains clorophyll C and A, Green algae contain clorphyll B and A, Red algae only contains A

Question 10

What is the evidence in which brown and green algae experience alternation of generations

Answer 10

They consist of multicellular diploid AND haploid phases

Question 11

Alternation of Generations in which haploid and diploid are identical

Answer 11

1. Sporophyte (dominant diploid form) produces spores by meiosis
2. Spores are haploid and divide mitotically to generate a multicellular gametophyte (can be seperate male and female or bisexual)
3. Gametophyte (haploid) produces sperm and egg which eventually fuse via fertilization (or syngamy)
4. The zygote has two copies of genes (diploid) and develops into a sporophyte and after some growth and cell divisiion, the zygote becomes an embryo
5. After the development of the sporphyte, life cycle being all over again