The catalyst for photosynthesis would be Manganese
Limiting factors refer to certain characteristics that affect a population in terms of growth and development. For instance, food scarcity. Without an abundant amount of food, organisms tend to lack such nutrients and the population eventually decreases. Under this idea, if there are too many deer in a forest, there won't be enough resources (food and water). Their population will decrease until the population growth limit is sustained.
They tried to connect the idea of stars with the sun
1- The Streptophyta super group includes the basal freshwater Charophyta plus the Embryophytes land plants
2 - The Chlorophyta is the sister clade of green algae that includes the marine species