LEC 2: ALGAE AND ALGAL SYMBIOSIS Flashcards
Are protists considered plants, animals or fungi?
Neither, they are the progenitor of all Eukaryotes
Why are protists that share similar characteristics with plants, like photosynthesis, not considered plants?
Because protist photosynthesizers have a different chloroplast endosymbiosis event
Explain why Algae are considered a polyphyletic group
Because although different species of algae share similar characteristics, they do not get those characteristic similarities from a common ancestor.
True or False; red algae must be red (color)
False, they do not always have to be red
What pigment causes a red color in Red Algae
Phycobiliprotein
What function(s) does phycobiliprotein serve in Red Algae
Helps with light capturing during photosynthesis and protects the algae from harmful UV rays
Do red algae harvest light directly? Why or why not?
Red algae only have phycobiliprotein and chlorophyll a pigments. They photosynthesize using these pigments but do not harvest light directly because they are missing chlorophyll b pigment.
What feature excludes red algae from the Viridiplantae class?
Red algae do not have Chlorophyll B pigment and are therefore not considered green/land plants
What is a Glaucophyte and what feature differentiates it from others of its kind?
- Glaucophytes are unicellular progenitors of green/red algae
- The membrane of its chloroplasts still have remnants of bacterial residue (peptidoglycan) which is typically degenerated by eukaryotic cells that have undergone endosymbiosis.
What two features are shared among all green algae?
- They all have Chlorophyll A and Chlorophyll B (light-harvesting) pigments
- They all store their starches in plastids.
What are three factors that make Chlamydomonas an valuable candidate of research?
- They have red eye spots on their chloroplasts that guide them towards light to help photosynthesis.
- They still have flagella that are used for motility and during the reproductive cycle.
- They have pyrenoids which are CCMs (carbon concentrating mechanisms) which are used when Oxygen levels are low.
True or False; all green plants must have a cell wall
False - some green plants do not
What is a zoospore?
Also known as a gamete, it is a halpoid cell
What are the chromosome counts for gametophyte cells and sporophyte cells?
Gametophytes are haploid and have a single set of chromosomes. Sporophytes are diploid and have two sets of chromosomes.
I am a composite organism made mostly of green algae as well as fungi and cyanobacteria. I live in a mutualistic symbiosis and you can find me in nearly all ecosystems. Who am I?
Lichen
What are a coupe of carotenoids functions?
It protects the cell from UV rays and helps obtain the energy from the sunlight.
What environmental shift causes the shift from asexual to sexual stage in Chlamydomonas?
Nitrogen starvation
What is a zygote?
A cell that is participating in the reproductive stage of a plant’s life cycle.
What is a Mycobiont?
The fungal part of Lichen that provides minerals and protection.
What is a Photobiont?
The photosynthesizing/green algae partner in Lichen that harvest light for energy in the form of carbohydrates.
What is a protoplasmic thread/conjugation tube? When is it formed?
Early in the reproductive stage, Chlamydomonas zygotes clump together close enough to which their flagella attach.
It is the attachment of flagella to create a tube by which cytoplasmic material is shared.
What are the five layers of lichen in order of closest to the surface to the farthest?
Cortex, photobiont layer, loosely packed hyphae, tightly woven lower cortex and anchoring hyphae called rhizines which attach to the substrate and helped in the terrestrialization of plants.
The process of exchanging cytoplasmic material is called what?
Plasmogamy
What stage of the life cycle are plasmogamy and karyogamy? (diploid/haploid)
Diploid (2n)
What process transitions a zygote from a zygospore?
The thickening of the cell wall
Can gametes divide by meiosis?
No
What is algal symbioses?
The mutualistic partnership between an algal partner and another organism
What two organisms have undergone algal symbioses?
Lichen and sea sponges
What are a coupe of carotenoids functions?
It protects the cell from UV rays and helps obtain the energy from the sunlight.
