Quiz 2 Flashcards
Eukaryote Domain
Eukarya
What happened 4.5 bya?
earth formed
What happened 3.7 bya?
first living organisms/first prokaryotes
What happened 2.7 bya?
first eukaryotes
How did eukaryotes arise?
One particular group of archaeans became so complex that they became eukaryotes. many mutations occurred over millions of years for this to happen.
Evidence of Endosymbiotic origin of mitochondria and chloroplast
- both mitochondria and chloroplast have their own DNA in 1 ring shaped chromosome
- mitochondria and chloroplast have their own ribosomes that are bacterial in design
- Mitochondria and chloroplast both have 2 membranes (inner-bacterial design, outer-eukaryotic)
Why is the “Kingdom Protista” invalid?
some protistans are more closely related to animals, fungi, or plants than to other protistans
How to recognize Protistan
eukaryotic, single cell, colonial, simple multicellular organism
Where do single-celled protistans live?
Freshwater, Marine, Parasites
How do single-celled protistans obtain nutrients?
many are photoautotrophic using photosynthesis, and many are chemoheterotrophic either absorbing molecules across the cell membrane, engulfing food, or using a mouth like structure to eat.
How do protistans move?
Some live attached to something else, float with no control of where they go, many swim using flagella or cilia, and some use ameboid locomotion
What are protistan shells made of?
Calcium carbonate, silicon, protein
What rock do calcium carbonate shells create?
calcium carbonate shells from protistans accumulate on the ocean floor, solidifying to form limestone.
What are the economic impacts of limestone?
Main ingredient in cement, fed to livestock and poultry as a calcium source, and used for gravel roads
