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 botany photosynthesis types of chlorophyll pigments photosynthetic pigments

The empirical formula for chlorophyll 'a' is ___________________.

  1. $C _{35}H _{72}O _{5}N _{4}Mg$
  2. $C _{35}H _{70}O _{6}N _{4}Mg$
  3. $C _{55}H _{72}O _{5}N _{4}Mg$
  4. $C _{54}H _{70}O _{6}N _{4}Mg$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Chlorophyll a is bluish-green with empirical formula of C55H72O5N4Mg

So the correct option is C.

Multiple choice botany photosynthesis types of chlorophyll pigments photosynthetic pigments

Bacteriochlorophyll differs from chlorophyll 'a' in having

  1. One pyrole ring with one hydrogen

  2. One pyrole ring with two hydrogen

  3. One pyrole ring with three hydrogen

  4. One pyrole ring with four hydrogen
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Purple sulphur bacteria and non-sulphur bacteria contain bacteria-chlorophyll,which is having 2H-atoms more than chl.a and it absorb 850-950 nm(infra-red) wavelength of light.

Multiple choice botany photosynthesis types of chlorophyll pigments photosynthetic pigments

Consider the following pigments.
a. Chlorophyll a
b. Chlorophyll b
c. Chlorophyll c
d. Carotenes
e. Biliproteins
f. Xanthophylls
The characteristic photosynthetic pigments present in chlorophyceae would include.

  1. $1, 2, 3$ and $4$
  2. $1, 3, 4$ and $5$
  3. $2, 3, 5$ and $6$
  4. $1, 2, 4$ and $6$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Chlorophyceae (green algae) typically contain chlorophyll a, chlorophyll b, carotenes, and xanthophylls.

Multiple choice botany photosynthesis types of chlorophyll pigments photosynthetic pigments

Energy transfer in photosynthesis occurs as

  1. Phycoerythrin$\rightarrow $Phycocyanin$\rightarrow $Carotenoid$\rightarrow $Chlorophyll a
  2. Chlorophyll b$\rightarrow $Carotenoid$\rightarrow $Phycoerthrin$\rightarrow $Chlorophyll a
  3. Phycocyanin$\rightarrow $Phycoerythrin$\rightarrow $Cartenoid$\rightarrow $Chlorophyll a
  4. Chlorophyll$\rightarrow $Cartenoid$\rightarrow $Phycocyanin$\rightarrow $Chlorophyll a
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

During photosynthesis, light energy is captured by accessory pigments and transferred efficiently toward the reaction center chlorophyll a. The correct energy transfer sequence is phycoerythrin to phycocyanin to carotenoids to chlorophyll a.

Multiple choice botany photosynthesis types of chlorophyll pigments photosynthetic pigments

Major Pigments in Phaeophycae :

  1. Chlorophyll $a$
  2. Chlorophyll $c$

  3. Fucoxanthin

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

Phaeophyceae, or brown algae, contain chlorophyll a, chlorophyll c, and carotenoids such as fucoxanthin, which give them their characteristic brown color. Since all the listed pigments are indeed found in brown algae, the correct choice is that all of the above are major pigments.

Multiple choice biology photosynthesis in higher plants types of chlorophyll pigments photosynthetic pigments

Which of the below statements is/are not correct regarding chlorophyll a molecule?

(i) Molecule formula of chl a is $C _{55}H _{72}O _5N _4Mg$
(ii) It is the primary photosynthetic pigment.
(iii) In the pure state, it is red in colour and thus it absorbs more blue wavelength of light than the red wavelength. 
(iv)It is a soluble in water as well as petroleum ether.

  1. (i) and (iii)

  2. (iii) and (iv)

  3. (ii) only

  4. (iv) only
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Chlorophyll a is the primary photosynthetic pigment, which is bluish green in the pure state. It has an empirical formula $C _{55}H _{72}O _5N _4Mg$and molecular weight of $893$. It absorbs more red wavelength of light than violet blue . It is soluble in a number of organic solvents such as petroleum ether. 

So, the correct answer is ' In the pure state, it is red in colour and thus it absorbs more blue wavelength of light than the red wavelength and It is a soluble in water as well as petroleum ether'.

Multiple choice

Chlorophyll is found in?

  1. nonvascular plants

  2. vascular plants

  3. neither

  4. both nonvascular and vascular plants
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Chlorophyll is the pigment responsible for photosynthesis and is found in both vascular plants and nonvascular plants like mosses and algae.

Multiple choice

The green pigment that absorbs sunlight is called?

  1. chlorine

  2. chlopofile

  3. chlorophyll

  4. flouride
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Chlorophyll is the green pigment found in chloroplasts that absorbs light energy to drive photosynthesis. Chlorine and fluoride are chemical elements, and chlopofile is a misspelling.

Multiple choice biology plant nutrition limiting factors factors affecting photosynthesis photosynthesis in higher plants

The law of limiting factor for photosynthesis was enunciated by 

  1. Blackman

  2. Hill

  3. Ruben

  4. Kalmen
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The main factors affecting rate of photosynthesis are light intensity, carbon dioxide concentration and temperature. In any given situation any one of these may become a limiting factor, in other words, the factors that directly affects the rate at which photosynthesis can take place masking the effects of the other factors. A limiting factor in a system is an input or variable such that a small change in it from the present value would cause a non-negligible change in an output or other measure of the system.  

Multiple choice biology plant nutrition limiting factors factors affecting photosynthesis photosynthesis in higher plants

According to Sachs, photosynthesis takes place at the

  1. Minimum value.

  2. Maximum value.

  3. Optimum value.

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

Blackman's Law of limiting factors are the various factors which affect the rate of photosynthesis. It is considered that when the other factors are constant, the factor which is least or minimum has the direct effect on the rate of photosynthesis. Sachs developed three cardinal points for each factor which affects the rate of photosynthesis. These cardinals have minimum, optimum and maximum values. The process of photosynthesis starts at the minimum and takes place at the optimum value. the rate of photosynthesis is much smaller at the maximum value and stops above this point.

Thus, the correct answer is option C.