Macroalgae Flashcards
What three things is seaweed classified by?
Pigments
Storage products
Flagella in spores
What is a frond?
Large leaf that is divided on a seaweed
What is the function of the blade on seaweed?
It captures light for photosynthesis
What is the stripe on a seaweed?
Stalk
What’s a holdfast on seaweed?
The root that holds seaweed to the substrate
What is green seaweed called?
Chlorophyta
What pigments does chlorophyta (green seaweed) contain?
Chlorophyll a and b
What light colours does chlorophyta use?
Red and blue light
What is the name for brown seaweed?
Phaeophyceae
What pigments does phaeophyceae contain?
Chlorophyll c and flucoxanthis
What light colours does phaeophyceae use?
Red and blue light but red mainly
What is the name for red seaweed?
Rhodophyta
What pigments does rhodophyta contain?
Chlorophyll and phycocyann and phycoerythrin
What light colours does rhodophyta absorb?
Blue light
What environment does chlorophyta enjoy?
Environments with fluctuating salinity and also fresh water.
What is the relation between the three types of seaweed?
They’re not closely related.
Why is rhodophyta good at CO2 sequestration?
It deposits CaCO3 into its cell walks which helps it act as a carbon sink.
Name 5 adaptations that help brown algae
Really reproductive-dioecious
Forms clumps-reduces evaporation
Grazing resistant
Thick cell walls-stops water loss
Resist desiccation-intertidal
What does being intertidal mean in terms of photosynthesis ability?
They photosynthesise more when exposed than when they’re submerged because water and particles also absorb light so less is available.
Where do brown algae live?
Rocky shores
What is sea grass classed as and why?
A plant because it has a complex root system unlike seaweed.
It has a vascular transport system
Higher cellulose content
What are the two stages of reproduction of seaweed?
- Gametophyte (makes gametes)
2. Sporophyte (makes spores)
How does reproduction look in green and brown algae?
Green: the same
Brown: different
Describe the process of the ulva life cycle and reproduction.
- Diploid sporophyte produces microscopic zoospores (with 4 flagella)
- Zoospores settle after 1 hour
- Zoospores germinate and produce the haploid gametophyte stage
