Volcanic eruptions like the one on the island of Krakatoa in Indonesia in 1883 can send huge quantities of ash into the atmosphere. This ash can partially block out the Sun's rays for days or weeks. What effect would this have on unicellular and multicellular plants?

As the earth formed, the force of gravity increased due to increased mass. what effect did this increased gravity have on the forming planet? the planet started to cool and an atmosphere formed. the planet started to become round and heat up. the planet started to wobble and turned upside down. the planet started to compress rock and form more radioactive elements.