Origin of Photosynthesis

Question 1

4.6 billion years ago

Answer 1

Formation of the earth

Question 2

3.4 billion years ago

Answer 2

First photosynthetic bacteria. They absorbed near-infrared rather than visible light and
produced sulfur or sulfate compounds rather than
oxygen. Their pigments (bacterio-chlorophylls)
were predecessors to chlorophyll.

Question 3

2.4 - 2.3 billion years ago

Answer 3

First rock evidence of atmospheric oxygen

Question 4

2.7 billion years ago

Answer 4

Cyanobacteria. These ubiquitous bacteria were the first oxygen producers. They
absorb visible light using a mix of pigments: phycobilins, carotenoids and several forms of chlorophyll.

Question 5

1.2 billion years ago

Answer 5

Red and brown algae. These
organisms have more complex cellular structures than bacteria do. Like cyanobacteria, they contain
phycobilin pigments as well as various forms of chlorophyll.

Question 6

0.75 billion years ago

Answer 6

Green algae. . . . doing better than red and brown algae in the strong light of shallow
water. They make do without phycobilins.

Question 7

0.475 billion years ago

Answer 7

First land plants. Mosses and
liverworts descended from green algae. Lacking
vascular structure (stems and roots) to pull waterfrom the soil, they are unable to grow tall.

Question 8

0.423 billion years ago

Answer 8

Vascular plants. These are literally garden-variety plants, such as ferns, grasses, trees and cacti. They are able to grow tall canopies to capture more light.