How is energy and matter transformed in the process of photosynthesis and cellular respiration? 

Expert Answers

An illustration of the letter 'A' in a speech bubbles

We know that energy and mass are neither created nor destroyed. They are just converted or transformed to other forms and ways. The two most important metabolic processes are the photosynthesis and cellular respiration.

Photosynthesis is the process of converting the light energy, usually coming from the sun, in the form of chemical energy that can be used as energy source of any living organisms. Plants and other organisms capable of doing photosynthesis are often called as the primary producers since they can be able to supply biomass or "food" to other organisms. 

In general, we can sum up the overall reaction of photosynthesis as:

`6 CO_2_(g) + 6H_2O _((l)) + light en ergy -> C_(6)H_(12)O_(6) _(s) + 6 O_2 _(g) `

We can see that carbon dioxide and water are converted into glucose and oxygen with the help of light energy. The masses are not destroyed but are transformed into different form that can be beneficial to other organisms. 

Cellular respiration is essentially is the "reverse" of the photosynthesis. It is a series of metabolic processes in which an organism is capable of converting the chemical energy into a more usable form of energy that can sustain the growth of the organism. This form of energy is the ATP or adenosine triphosphate. All organisms are capable of performing cellular respiration (aerobic and anaerobic).

The over-all reaction of aerobic cellular respiration can be simplified as:

`C_(6)H_(12)O_(6) _(s) + 6 O_2 _(g) ->6 CO_2 _(g) + 6H_2O _((l)) + en ergy `

We can see that the energy and mass are transformed in other forms via cellular respiration and photosynthesis. Plants breathe carbon dioxide and expel oxygen. On the contrary, humans and animals breathe oxygen and expel carbon dioxide. These are vital processes that sustain the life of the organisms in this planet. 

Approved by eNotes Editorial
An illustration of the letter 'A' in a speech bubbles

What is a matter transformation and energy transformation in photosynthesis?

Photosynthesis is the process by which plants convert carbon dioxide and water into glucose and oxygen in the presence of sunlight. The balanced chemical reaction for this process can be written as:

`6CO_2 (g) + 6H_2O (aq) + sunlight -> C_6H_12O_6 (s) + 6O_2 (g)`

There are different phases (or states) of matter, such as solid, liquid, gas and plasma. Photosynthesis represents the consumption of some reactants and production of some products, during which phase transformations take place. For example, carbon dioxide is in the gas phase and water is in the liquid or aqueous phase, while glucose is in its solid phase and oxygen is in its gas phase. Photosynthesis involves matter transforming into entirely new molecules in different physical states.

This process also involves energy transformations. Photosynthesis uses the light energy of the sun and converts it to chemical energy (stored in glucose molecules). The chemical energy of glucose is converted to ATP molecules during the process of cellular respiration and is then used by organisms. 

Thus, photosynthesis involves both matter and energy transformations. 

Hope this helps. 

See eNotes Ad-Free

Start your 48-hour free trial to get access to more than 30,000 additional guides and more than 350,000 Homework Help questions answered by our experts.

Get 48 Hours Free Access
Last Updated on