Why are oceans called the planets lungs?

Oceans are called the “planet’s lungs” because they play a crucial role in producing oxygen and absorbing carbon dioxide. Marine plants, such as phytoplankton, in the oceans perform photosynthesis, similar to plants on land, releasing oxygen into the atmosphere. This process helps maintain the balance of gases in the Earth’s atmosphere, supporting life on the planet. Additionally, oceans act as a carbon sink, absorbing carbon dioxide from the air, which helps regulate the Earth’s climate. This vital function of the oceans is why they are often referred to as the “lungs” of the planet.

This question related to Chapter 2 Social Science Class 6th NCERT.
From the Chapter 2. Oceans and Continents.
Give answer according to your understanding.