Photosynthetic Protists – Algae, Diatoms, Dinoflagellates

Diatoms: The Jewels of the Sea

Part 1:  Photosynthetic Protists – Algae
Diatoms – video: Diatoms (watch from 1:25 min)
Diatoms are unicellular algae
1)Why are diatoms considered the jewels of the sea, describe their structure? 

2)Describe the two forms of diatom reproduction?

Dinoflagellates
“Dinos” means whirling in Greek.  These organisms whirl because of the two flagella located in perpendicular grooves.  Dinoflagellates may be photosynthetic, heterotrophic or mixotrophic (both).  They are an important component of plankton.

1)Diatoms and Dinoflagellates are considered to be Planktonic. What does the word plankton refer to (0.5)? List two other types of plankton that are not protists (0.5). State one reason plankton are important (1). Ideas can be found here: Plankton

2)Watch the video on coral bleaching: coral bleaching
What two organisms make up the symbiosis found in coral?
What causes coral bleaching?

3)Research on coral resiliency is investigated here: Coral reef research
Describe the experiment (2) What factors are important to coral survival?

4)What causes dinoflagellate bioluminescence? What is the most dominant hypothesis explaining why dinoflagellates send out this light signal? (2) Dinoflagellates

5)‘Red tide’ is caused by a bloom of dinoflagellates.  What is a “bloom” and why is this particular bloom dangerous to humans? (1.5) (refer to PowerPoint or research the internet)

Chlorophyta: Green Algae
Land plants share a common ancestor with green algae.  They share the same photosynthetic pigments, store energy as starch and share other characteristics not found in the other types of algae.  Green algae have many 'body forms'.  Some algae are unicellular, some are filamentous, some are colonial, and some are multicellular.

Video: green algae - unicellular to multicellular (watch video from 3:34 to 5:45)
Volvox forms colonies of single cells held together with gelatinous material.  In some colonies the cells are connected to each other by strands of cytoplasm.  As a colony, the cells live together, move together, and share nutrients.  This colony of green algae looks like a ball with many tiny green 'dots'.  The little green dots are individual cells.    

1)Draw a unicellular Chlamydomonas and a multicellular Volvox

2)What allowed multicellularity to occur in this group of green algae, specifically what happens during cell division? (1)

 
Multicellular Green Algae:  Ulva
You have probably encountered many types of multicellular green algae whenever you’ve walked along a marine beach at low tide.  They tend to have very descriptive names such as sea lettuce (Ulva), sea moss, and sea hair.

1)Go for a walk at the beach. Take a photo of you with Ulva or another type of multicellular green algae. (1.5) If you cannot find green algae take a photo of brown algae (e.g. Rockweed, or washed up Bull Kelp)

Clade SAR:  Brown Algae
Brown algae are large, multicellular algae.  They are the dominant “seaweed” species found along our marine rocky shores.  

1)Explain three reasons why kelp is important (as stated in the video).
Video: The importance of kelp

2)Draw bull kelp, Nereocystis luetkeana. Be sure to include labels (refer to the Protist PowerPoint).