Question

The first scientist to find out the role of light in photosynthesis was
(a) Ingenhousz
(b) Senebier
(c) Priestley
(d) Sachs

Answer 1

Hint: He was born in Dutch, a British physician, and scientist who is best known for his discovery of the method of photosynthesis, by which green plants in sunlight absorb ${CO_2}$ and release oxygen.

Complete answer:
Jan Ingenhousz was born on December 8, 1730—died September 7, 1799, he discovered the use of light in the process of photosynthesis. Photosynthesis is the phenomenon where the energy is supplied from sunlight and is used by various plants, animals, protistan, and some bacteria to supply sugar, which is converted into ATP by respiration. ATP is known as the "fuel" that is used by all living things. The conversion of unusable sunlight energy into usable energy is related to the actions of the green pigment chlorophyll.
$ {6H_2O+6CO_2C_6H_{12}O_6+6O_2}$
Ingenhousz stated that :
(1) Light is important for this restoration (photosynthesis);
(2) The photosynthesis is performed by only the green plants
(3) As all the living parts of the plant respire or “damage” the air, but the green plants far exceed its damaging effect by increasing their extent of air restoration by a green plant.
So the correct answer is ‘(a) Ingenhousz’.

Additional Information: Photosynthesis is that the process by which plants and a few other living organisms derive energy from light sources—usually the sun. Although this important process has existed since the start of your time, everyone was totally oblivious of its existence, and it wasn’t discovered until the 1800s. There is not only one scientist who was responsible for this discovery, as several different scientists over a period of quite 200 years contributed to the invention of this important phenomenon.
It would be impossible to overestimate the importance of photosynthesis within the maintenance of life on Earth. If photosynthesis is decreased there would soon be little food or other organic matter on Earth. Most organisms would disappear, and in time Earth’s atmosphere would become nearly barren of gaseous oxygen. Chemosynthetic bacteria are the only organism that can survive under such conditions.
Ingenhousz, who had great scientific interests in various fields, also invented an improved apparatus for generating large amounts of electricity (1766) and made the primary quantitative measurements of warmth conduction in metal rods (1789) .
Further ideas were caused within the late 1700s. Jan Ingenhousz and Jean Senebier found that the air is merely reviving within the daytime which ${CO_2}$ is assembled by plants.

Note: Van Helmont had placed a large pot exactly 200 pounds (91 kg) of soil that had been thoroughly dried in an oven. Then he moistened the soil with rainwater and planted a 5-pound (2.3 kg) willow shoot in it. He then placed the pot within the ground and covered its rim with a perforated iron plate. The perforations allowed water and air to succeed in the soil but lessened the prospect that dirt or other debris would be blown into the pot from the surface. The first evidence that gases participate in photosynthesis was reported by Priestley in 1772. Priestley discovered that if a plant is placed in an environment lacking oxygen, it soon replenishes the oxygen, and a mouse can survive within the resulting mixture. Priestley thought (erroneously) that it had been simply the expansion of the plant that accounted for this.