Why do cyanobacteria and algae take in carbon dioxide and give off oxygen?

Verified step by step guidance

1. Understand that cyanobacteria and algae are photosynthetic organisms, meaning they can convert light energy into chemical energy.
2. Recognize that during photosynthesis, these organisms use carbon dioxide (CO2) and water (H2O) as raw materials.
3. Learn that the process of photosynthesis occurs in two main stages: the light-dependent reactions and the Calvin cycle (light-independent reactions).
4. In the light-dependent reactions, light energy is absorbed by chlorophyll, exciting electrons and splitting water molecules, releasing oxygen (O2) as a byproduct.
5. In the Calvin cycle, the energy from ATP and NADPH (produced in the light-dependent reactions) is used to convert CO2 into glucose, a process known as carbon fixation.

Key Concepts

Photosynthesis

Photosynthesis is the biochemical process by which organisms like cyanobacteria and algae convert light energy into chemical energy. During this process, they absorb carbon dioxide (CO2) and water (H2O) to produce glucose and oxygen (O2) as byproducts. This process is essential for the survival of these organisms and plays a crucial role in the Earth's carbon cycle.

Chlorophyll and Light Absorption

Chlorophyll is the green pigment found in cyanobacteria and algae that captures light energy from the sun. This energy is used to drive the photosynthetic reactions, allowing these organisms to convert CO2 and H2O into glucose. The absorption of light is vital for the efficiency of photosynthesis, as it provides the energy needed for the conversion process.

Oxygenic Photosynthesis

Oxygenic photosynthesis is a type of photosynthesis that produces oxygen as a byproduct. In this process, water molecules are split to release oxygen, which is then expelled into the atmosphere. Cyanobacteria and algae are key players in this process, contributing significantly to the oxygen levels in Earth's atmosphere and supporting aerobic life forms.