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This section includes 37 Mcqs, each offering curated multiple-choice questions to sharpen your Biology knowledge and support exam preparation. Choose a topic below to get started.
1. |
Which of the following inhibits \[{{O}_{2}}\] release in light phase [DPMT 2004] |
A. | PMA |
B. | Zeatin |
C. | DCMU |
D. | None of these |
Answer» D. None of these | |
2. |
The most effective wavelength of visible light in photosynthesis is in the region of [AFMC 1989, 2003; MP PMT 1989, 2000; CPMT 1990, 2000; DPMT 1986, 87, 2004; CBSE PMT 1999; RPMT 1999; Kerala CET 2003] |
A. | Violet |
B. | Green |
C. | Yellow |
D. | Red |
Answer» E. | |
3. |
Emmerson defined 'red drop' as a decline in photosynthesis also termed Emmerson's effect. It appears at |
A. | 460 nm wavelength |
B. | 630 nm wavelength |
C. | 680 nm wavelength |
D. | 680 nm wavelength |
Answer» E. | |
4. |
Under conditions of constant illumination, the compensation period for a whole aquarium would be of infinite length when |
A. | The biomass of animals equals the biomass of plants |
B. | The respiratory exchanges of the animals are equal to the photosynthetic exchanges of the plants |
C. | The oxygen intake of the animals equals of oxygen output of photosynthesis |
D. | The carbon dioxide output of the animals and plants equals to the photosynthetic intake of the plants |
Answer» E. | |
5. |
If water supply to the plant is extremely meagre to as to cause wilting of leaves, the rate of photosynthesis may |
A. | Increase |
B. | Decrease |
C. | First increase than decrease |
D. | First decrease than increase |
Answer» C. First increase than decrease | |
6. |
Warburg studied his effect on |
A. | Chlamydomonas |
B. | Chlorella |
C. | Volvox |
D. | All the above |
Answer» C. Volvox | |
7. |
What plant is used in an experiment commonly performed in laboratory in demonstrate evolution of oxygen in photosynthesis [RPMT 1997] |
A. | Sunflower |
B. | Hydrilla |
C. | Croton |
D. | Balsam |
Answer» C. Croton | |
8. |
The thylakoids are removed and kept in a culture medium containing\[C{{O}_{2}}\]and\[{{H}_{2}}O\]. If the setup is exposed to light, hexose sugars are not formed as the end product. The most appropriate reason for this will be that [AIIMS 1980, 85] |
A. | Carbon assimilation cannot take place |
B. | The pigments (P-700 and P-680) are not linked |
C. | Enzymes are not available |
D. | The light trapping device is not functional |
Answer» D. The light trapping device is not functional | |
9. |
The path of\[C{{O}_{2}}\]in the dark reaction of photosynthesis was successfully traced by the use of the following or The dark reaction is traced by [CPMT 1990; MP PMT 1987; BHU 1992] |
A. | \[{{O}_{2}}^{18}\] |
B. | \[{{C}^{14}}{{O}_{2}}\] |
C. | \[{{p}^{36}}\] |
D. | X-rays |
Answer» C. \[{{p}^{36}}\] | |
10. |
Sedohaptulose is a carbohydrate having |
A. | 3 carbon atoms |
B. | 2 carbon atoms |
C. | 4 carbon atoms |
D. | 7 carbon atoms |
Answer» E. | |
11. |
Radioactive\[{{C}^{14}}\]is given to\[C{{O}_{2}}\]and released to atmosphere. This\[C{{O}_{2}}\]is taken by RuBP in a\[{{C}_{3}}\]plant. First radioactive\[{{C}^{14}}\]is seen in which compound [Manipal 2005] |
A. | PGAL |
B. | PEP |
C. | RMP |
D. | PGA |
Answer» E. | |
12. |
The first step in dark reaction of photosynthesis is [CPMT 2004] |
A. | Formation of ATP |
B. | Ionization of water |
C. | Attachment of \[C{{O}_{2}}\] to a pentose sugar |
D. | Excitement of electron of chlorophyll by a photon of light |
Answer» D. Excitement of electron of chlorophyll by a photon of light | |
13. |
Carbon dioxide is fixed in [MP PMT 1999] |
A. | Light reaction |
B. | Dark reaction |
C. | Aerobic respiration |
D. | Anaerobic respiration |
Answer» C. Aerobic respiration | |
14. |
Dark reaction of photosynthesis take place in [CPMT 1986, 90; RPMT 1995; MP PMT 2000] |
A. | Grana |
B. | Stroma |
C. | Matrix |
D. | Cytoplasm |
Answer» C. Matrix | |
15. |
In\[{{C}_{4}}\]plants,\[C{{O}_{2}}\]combine with PEP in presence of [CPMT 1990] |
A. | PEP carboxylase |
B. | RuBP carboxylase |
C. | RuBP oxygenase |
D. | Hydrogenase |
Answer» B. RuBP carboxylase | |
16. |
Which of the following may show photosynthesis in moonlight |
A. | Some thermal algae |
B. | Some marine algae |
C. | Some fresh water algae |
D. | None of the above |
Answer» C. Some fresh water algae | |
17. |
Photosynthesis will proceed upto |
A. | Limit of light |
B. | Limit of wind |
C. | Limit of moisture |
D. | None of the above |
Answer» B. Limit of wind | |
18. |
Bacteriochlorophyll differs from chlorophyll 'a' in having [CPMT 1989] |
A. | One pyrrol ring with one hydrogen |
B. | One pyrrol ring with two hydrogen |
C. | One pyrrol ring with three hydrogen |
D. | One pyrrol ring with four hydrogen |
Answer» C. One pyrrol ring with three hydrogen | |
19. |
Photosynthesis consists of essentially two biological reaction systems, one followed by the other, the second of these systems does which of the following [CPMT 1988] |
A. | Fixes\[C{{O}_{2}}\] |
B. | Traps light energy |
C. | Synthesizes starch |
D. | Works only in the presence of light |
Answer» B. Traps light energy | |
20. |
Chlorophyll 'a' is found in [CBSE PMT 1992] |
A. | All oxygen releasing photosynthetic forms |
B. | All plants except fungi |
C. | All higher plants that photosynthesize |
D. | All photosynthetic prokaryotes and eukaryotes |
Answer» B. All plants except fungi | |
21. |
Which of the plants can show CAM cycle |
A. | Members of graminae |
B. | Members of cactaceae |
C. | Members of chenopodiaceae |
D. | All the above |
Answer» C. Members of chenopodiaceae | |
22. |
No. of carboxylation in \[{{C}_{4}}\]cycle is/are [DPMT 2003] |
A. | 1 |
B. | 2 |
C. | 5 |
D. | 3 |
Answer» C. 5 | |
23. |
How many types of photosynthetic cells occur in\[{{C}_{4}}\]plant |
A. | One type |
B. | Two types |
C. | Four types |
D. | Eight types |
Answer» C. Four types | |
24. |
CAM photosynthesis occurs in plants with [MP PMT 1993] |
A. | Thin green leaves with reticulate venation |
B. | Thin green leaves with parallel venation |
C. | Fleshy green leaves |
D. | Thin coloured leaves |
Answer» D. Thin coloured leaves | |
25. |
Which of the following is essential for the normal growth of \[{{C}_{4}}\] plants |
A. | Silicon (100 m) |
B. | Vanadium\[(100\mu m)\] |
C. | Sodium (100 m) |
D. | Barium (100 m) |
Answer» D. Barium (100 m) | |
26. |
Atriplex spongiosa is a |
A. | \[{{C}_{3}}\]plant |
B. | \[{{C}_{4}}\]plant |
C. | CAM plant |
D. | All the above |
Answer» C. CAM plant | |
27. |
Which of the following is a CAM plant |
A. | Maize |
B. | Sugarcane |
C. | Agave |
D. | Mango |
Answer» D. Mango | |
28. |
Which of the following is \[C{{O}_{2}}\] acceptor in \[{{C}_{4}}\] plants [CPMT 1986,2004; AMU 1987; CBSE PMT 1990; BHU 1994, 2000; MP PMT 1996; CPMT 1998; Orissa PMT 2002; BVP 2002] |
A. | Phosphoenol pyruvate (PEP) |
B. | Ribulose 1, 5 diphosphate (RuDP) |
C. | Oxaloacetic acid (OAA) |
D. | Phosphoglyceric acid (PGA) |
Answer» B. Ribulose 1, 5 diphosphate (RuDP) | |
29. |
Which one is a\[{{C}_{4}}\]plant [BHU 1979, 82; DPMT 1984; CBSE PMT 1988; MP PMT 1993, 95] |
A. | Papaya |
B. | Pea |
C. | Potato |
D. | Maize |
Answer» E. | |
30. |
Green bacteria contains |
A. | Chlorobium chlorophyll-660 |
B. | Chlorobium chlorophyll-650 |
C. | Both [a] and [b] |
D. | Chlorobium chlorophyll-700 |
Answer» D. Chlorobium chlorophyll-700 | |
31. |
Photosynthetic pigments in bacteria are located in [Wardha 2005] |
A. | Thylakoid mambrane |
B. | Cytoplasm |
C. | Chloroplast membrane |
D. | Ribosomes |
Answer» B. Cytoplasm | |
32. |
What is the bye-product of bacterial photosynthesis |
A. | \[{{O}_{2}}\] |
B. | \[{{H}_{2}}O\] |
C. | \[S\] |
D. | \[{{H}_{2}}S\] |
Answer» D. \[{{H}_{2}}S\] | |
33. |
Assertion : CAM plants lack structural compartmentation of leaf, as found in\[{{C}_{4}}\]plants. Reason : Stomata of CAM plants are open during the day. |
A. | If both the assertion and the reason are true and the reason is a correct explanation of the assertion |
B. | If both the assertion and reason are true but the reason is not a correct explanation of the assertion |
C. | If the assertion is true but the reason is false |
D. | If both the assertion and reason are false |
E. | If the assertion is false but reason is true |
Answer» D. If both the assertion and reason are false | |
34. |
Assertion : Photorespiration is completed in three cell organelles. Reason : Peroxisomes, glyoxysomes and desmosomes are involved in photorespiration. |
A. | If both the assertion and the reason are true and the reason is a correct explanation of the assertion |
B. | If both the assertion and reason are true but the reason is not a correct explanation of the assertion |
C. | If the assertion is true but the reason is false |
D. | If both the assertion and reason are false |
E. | If the assertion is false but reason is true |
Answer» D. If both the assertion and reason are false | |
35. |
Assertion : Six molecules of\[C{{O}_{2}}\] and twelve molecules of \[NADP{{H}^{+}}+{{H}^{+}}\]and 18 ATP are used to form one hexose molecule. Reason : Light reaction results in formation of \[ATP\]and \[NADP{{H}_{2}}\] [AIIMS 2002] |
A. | If both the assertion and the reason are true and the reason is a correct explanation of the assertion |
B. | If both the assertion and reason are true but the reason is not a correct explanation of the assertion |
C. | If the assertion is true but the reason is false |
D. | If both the assertion and reason are false |
E. | If the assertion is false but reason is true |
Answer» C. If the assertion is true but the reason is false | |
36. |
Assertion : Sciophytes require higher light intensity than heliophytes. Reason : Sciophytes grow below the canopy of trees. |
A. | If both the assertion and the reason are true and the reason is a correct explanation of the assertion |
B. | If both the assertion and reason are true but the reason is not a correct explanation of the assertion |
C. | If the assertion is true but the reason is false |
D. | If both the assertion and reason are false |
E. | If the assertion is false but reason is true |
Answer» F. | |
37. |
Assertion : Oxidative phosphorylation requires oxygen. Reason : Oxidative photophosphorylation occurs in mitochondria. |
A. | If both the assertion and the reason are true and the reason is a correct explanation of the assertion |
B. | If both the assertion and reason are true but the reason is not a correct explanation of the assertion |
C. | If the assertion is true but the reason is false |
D. | If both the assertion and reason are false |
E. | If the assertion is false but reason is true |
Answer» C. If the assertion is true but the reason is false | |