Biology

Photosynthesis in Plants

1,508 Questions

Photosynthesis is the biological process by which plants convert light energy into chemical energy. This page contains practice questions covering essential topics like chlorophyll, light reactions, and the pathways specific to plants. This material is crucial for medical entrance exams and academic assessments.

Chlorophyll and pigmentsLight reactionsCalvin cycleCAM plantsElectron transportPhotosynthesis factors

Photosynthesis in Plants Questions

Multiple choice bio-chemistry carbohydrate metabolism energy output living organisms and energy production respiration in cell

In photosynthesis energy from light reaction to dark reaction is transferred in the form of 

  1. ADP

  2. ATP

  3. RUDP

  4. Chlorophyll
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

ATP is the energy currency. Assimilatory power is the power of plants in the form of ATP and NADPH to obtain food in the form of carbohydrates from the reduction of $CO _2$ during photosynthesis.

Multiple choice bio-chemistry carbohydrate metabolism energy output living organisms and energy production respiration in cell

If $4$ molecules of glucose are synthesized during photosynthesis, how many ATP molecules are released and how many molecules of ATP are utilized respectively?

  1. $8 ATP, 72 ATP$
  2. $2 ATP, 18 ATP$
  3. $8 ATP, 36 ATP$
  4. $4 ATP, 36 ATP$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
For the synthesis of one molecule of glucose by photosynthesis, 2 ATP molecules are released and 18 ATP molecules are utilized. 18 ATP molecules are utilized in the sense that in most of the plants the mode of CO$ _2$ fixation is C$ _3$ cycle or Calvin cycle. In C$ _3$ cycle for each molecule of CO$ _2$ to be fixed, 3 ATP are required. Thus, for the synthesis of one Glucose molecule, 6 CO$ _2$ molecules are fixed. Thus, 18 ATP molecules in total are utilized for the formation of one Glucose molecule.
Hence, for the synthesis of 4 glucose molecules in photosynthesis,
ATP molecules released = 4 × 2 = 8
ATP molecules utilized = 4 × 18 = 72.
So, the correct answer is A.
Multiple choice botany adaptations to different ecosystems lichen lichens lichens ( the nature's pioneers )

Which of the following physiological process happens in lichens when the phycobiont is a cyanobacteria?

  1. Nitrogen fixation

  2. Carbon fixation

  3. Carbon assimilation

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The fungal part of the lichens is known as mycobiont. Cyanobacteria have a special structure known as heterocyst which is specialised to perform nitrogen fixation. It has specific enzymes like nitrogenase which actively fixes the atmospheric nitrogen to a usable form. They are autotrophic so they also fix carbon during the dark reaction of photosynthesis into organic compounds. This conversion process of inorganic carbon (carbon dioxide) to organic compounds is also known as carbon assimilation.

So, the correct answer is 'Nitrogen fixation, Carbon fixation and Carbon assimilation'.

Multiple choice botany cell structure and organization membrane bound organelles cell: size and differentiation microscopy

Anthocyanin occurs in

  1. Chloroplasts

  2. Vacuole

  3. Leucoplasts

  4. Chromoplasts
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
  • The plant vacuoles consist of various water-soluble pigments such as carotenoids, anthocyanins and xanthophylls etc.
  • Anthocyanins are also water-soluble pigments which are red, purple, or blue in colour depending on the pH which gives colour to the flower and fruits (blueberry, raspberry etc).
  • So, the correct answer is 'Vacuoles'.
Multiple choice

In which location does the Calvin Cycle take place?

  1. thylakoid membrane

  2. cytoplasm

  3. cytoplasm

  4. stroma in chloroplast
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The Calvin Cycle occurs in the stroma, which is the fluid-filled space surrounding the thylakoids inside the chloroplast.