Endosymbiosis Flashcards
What is the difference between digestion and endosymbiosis?
Digestion results in the breakdown of cellular material of prey for food
Endosymbiosis is an engulfment where some DNA is transported to the hosts nucleus
What is secondary endosymbiosis?
Some groups appear to have both lost their original chloroplasts then acquired a new type of chloroplast by engulfing a photosynthetic eukaryote.
What are planktonic organisms?
Organisms whose movement is dictated by the movement of the water
Can come in many shapes and sizes
Can be autotrophic, heterotrophic, mixotrophic,
What are the plankton size classes?
- Eukaryotic zooplankton (multicellular)
- Eukaryotic phytoplankton and zooplankton (single-celled)
- Bacteria
What are microalgae?
A generic term for microscopic, floating photosynthetic organisms
What are the different classes for microalgae?
- Cyanophyceae = cyanobacteria
- Bacillariophyceae = diatoms
- Dinophyceae = dinoflagellates
- Haptophyceae = coccolithophores
- Dictyochophyceae = silicoflagellate
What are phytoplankton?
The photosynthetic component of plankton consisting primarily of single-celled algae and cyanobacteria
What are the common features of phytoplankton?
Usually microscopic size
Most have adaptations to maintain position in the photic zone
Reproduction can be either/or asexual or sexual
All respire and photosynthesize
What is the photic zone?
The surface of water column in ocean where there is enough light for PS to occur
What are diatoms?
Unicellular photoautotrophs
Can be round or boat-shaped Have cell wall called frustule made of silicon and have two valves
The celllwall consists of two fitting halves.
Describe asexual reproduction of diatoms
Frustules separate and each forms a new smaller fiatom
Eventually diatoms become too small to divide asexually
Describe sexual reproduction of diatoms
Small diatoms no longer capable of dividing produce gametes and cross fertilize
Fertilized small diatoms shed frustules and produce a naked cell called the auxospore
Auxospores enlarge to orginal cell size and form a new frustule
Why are diatoms important?
They are the base of food web
Dominant fixer of carbon dioxide
