Photosynthesis VS Cellular Respiration

Photosynthesis vs Respiration

Photosynthesis and respiration are reactions that complement each other in the environment. They are in reality the same reactions but occurring in reverse. While in photosynthesis carbon dioxide and water yield glucose and oxygen, through the respiration process glucose and oxygen yield carbon dioxide and water.
They work well since living organisms supply plants with carbon dioxide which undergoes photosynthesis and produces glucose and these plants and bacteria give out oxygen which all living organisms need for respiration.

Comparison chart

 

Improve this chart	Photosynthesis	Respiration
Main function:	Production of food. Energy Capture.	Breakdown of food. Energy release.
Electron Carrier:	NADPH	NADH
Electron source:	Oxidation H2O at PSII	NADH + FADH2
What pumps protons across the membrane:	C	Complex I, III, IV
What powers ATP synthesase:	H+ gradient across thylakoid membrane. High H+ concentration in the thylakoid space	H+ gradient across the inner mitochondria membrane. High H+ concentration in the intermembrane space
Process:	The production of organic carbon (glucose and starch) from inorganic carbon (carbon dioxide) with the use of ATP and NADPH produced in the light dependent reaction	The production of ATP from the oxidation of organic sugar compounds.
Fate of oxygen and carbon dioxide:	Carbon dioxide is absorbed and oxygen is released.	Oxygen is absorbed and carbon dioxide is released.
Occurrence:	Occurs in plants and some bacteria.	Occurs in all living organisms.
Location:	chloroplasts	mitochondria
Product:	C6H12O6 and O2	CO2 and H2O
Reactants:	CO2 and H2O	C6H12O6 and O2
Equation:	6CO2 + 6H2O light --> C6H12O6 + 6O2	6O2 + C6H12O6 --> 6CO2 +6H2O + energy
Production of ATP:	yes	yes, 36-38
Requirement of sunlight:	Can occur only in presence of sunlight	Occurs at all times.
Chemical reaction:	Carbon dioxide and water combine in presence of sunlight to produce glucose.	Glucose is broken down into water and carbon dioxide.
Final electron receptor:	NADP+	Oxygen
Catalyst:	Reaction takes places in presence of chlorophyll.	No catalyst is required for respiration reaction.
Stages:	2 stages (The light dependent reaction, light independent reaction).	3 stages (Glycolysis, Link reaction, Krebs cycle).

 

Photosynthesis is a process that converts carbon dioxide into organic compounds in presence of sunlight. Respiration is the set of metabolic reactions that take in cells of living organisms that convert nutrients like sugar into ATP (adenosine tri phosphate) and waste products.

Processes in photosynthesis are divided on basis of requirement of sunlight while respiration processes are divided on basis of requirement of oxygen. Hence in photosynthesis you have the light dependent reactions and the dark reactions while in respiration there is aerobic respiration and anaerobic respiration.
In photosynthesis light dependent reactions, ultra violet light strikes chlorophyll pigments which excites electrons leading to separation of oxygen molecules from carbon dioxide. In the dark reactions, carbon molecules now independent of oxygen are converted into carbohydrates and stored in plant cells as energy and food source. In aerobic cellular respiration oxygen is utilized to convert organic compounds into energy and in anaerobic respiration converts organic compounds into energy without using oxygen.

Photosynthesis takes place in the chloroplasts and organelles of a plant cell. Respiration takes place in the cytoplasm and mitochondria in the cell of a living organism.

Reaction kinetics

The electron acceptor in photosynthesis is NAD+ while in respiration the electron acceptor is NADH. In cellular respiration reaction 36 molecules of ATP are produced in complete oxidation of one molecule of glucose.