During cellular respiration, carbon dioxide is released to the atmosphere during the formation of acetyl coenzyme A<span>. This step involves the oxidative decarboxylation of pyruvic acid, the result of which is carbon dioxide. This carbon dioxide is uptaken by plants and used in the process of photosynthesis to produce glucose.</span>
Answer:
Due to presence at early days of the planet.
Explanation:
We only find the remains of single celled organisms in the oldest fossils because the single celled organisms are the organisms that were present in the early days of this planet. These single celled microbes were present about 3.7 billion years ago while on the other hand, the oldest rocks are only a little older i. e. 3.8 billion years so these single celled organisms are considered as oldest fossils on this planet.
Two partial cells, which are still forming into real cells
The right answer is b. Tree.
Some plants (like trees) have evolved with different unusual nutritional adaptations over time. Heterotrophic plants are plants that use only or partly a source of organic carbon to grow, unlike the most common autotrophic plants, which use inorganic carbon and water to grow, often through the process of photosynthesis (photoautotrophic).