Explore topic-wise MCQs in Biology.

This section includes 32 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 plant hormone substitutes for long photoperiods in flowering plants [CPMT 1990; BHU 2004]

A. Auxins
B. Gibberellins
C. Cytokinins
D. Ethylene
Answer» C. Cytokinins
2.

Gibberellins were first discovered in fungal genus [MP PMT 1999]

A. Mucor
B. Rhizopus
C. Agaricus
D. Fusarium
Answer» E.
3.

Gibberellins cause or Gibberellins stimulate [BHU 1988; CPMT 1988; RPMT 1984]

A. Elongation of internodes
B. Curvature of coleoptile
C. Cell division
D. Initiation of lateral roots
Answer» B. Curvature of coleoptile
4.

The ripening of fruits can be hastened by treatment with [CPMT 1994, 2001, 03; BHU 1990, 95, 2000; AMU 1989; MP PMT 1994; KCET 2000]

A. Gibberellic acid
B. Indole acetic acid
C. Florigen
D. Ethylene gas
Answer» E.
5.

Which hormone induces fruit ripening [Orissa JEE 2004; HP PMT 2005]

A. Auxin
B. Cytokinin
C. Gibberellin
D. Ethylene
Answer» E.
6.

Ethylene gas [BHU 1985, 94; CPMT 1989]

A. Is a saturated hydrocarbon
B. Slows down the ripening of apples
C. Retards ripening of tomatoes
D. Speeds up maturation of fruits and early ripening of some fruits
Answer» E.
7.

For plant tissue culture, among the following which one is required [BHU 1983]

A. Trypsin
B. Kinetin
C. Caffeine
D. Coumarine
Answer» C. Caffeine
8.

Cytokinins are formed in [BVP 2004]

A. Roots
B. Leaves
C. Fruits
D. Stems
Answer» B. Leaves
9.

The cut flowers and vegetables can be kept fresh a long period by this plant hormone [Kerala PMT 2004]

A. Gibberellins
B. Cytokinins
C. Auxins
D. Ethylene
E. 2,4-dichlorophenoxy actic acid
Answer» C. Auxins
10.

The chief role of cytokinin is

A. To check senescence
B. To check evaporation
C. To check abscission
D. To mobilise solutes to different parts of plant and check senescence
Answer» E.
11.

Cambial tissue of Pinus radiata contains

A. Auxins
B. Gibberellins
C. Cytokinin
D. None of the above
Answer» D. None of the above
12.

Discovery of which one of following is connected with the use of an old sample of DNA in a culture medium

A. Cytokinins
B. ABA
C. Vitamin K
D. Pantothanic acid
Answer» B. ABA
13.

A plant placed near a window bends outwards because [CPMT 1989]

A. Its tip is able to get more oxygen
B. Its tip is able to obtain more light
C. Its tip is able to receive necessary warmth
D. The auxin contents on the shadow side is higher than that on the lighter side and as a result the shaded side elongate more than the cells on the illuminated side and the tip bends outwards
Answer» E.
14.

What will be the effect on phytochrome in a plant subjected to continuous red light [CBSE PMT 1997]

A. Level of phytochrome will decrease
B. Phytochrome will be destroyed
C. Phytochrome synthesis will increase
D. None of these
Answer» E.
15.

Agenetically dwarf plant can be converted into a tall plant by the use of [MP PMT 1996]

A. Kinetin
B. \[G{{A}_{3}}\]
C. IAA/X-rays
D. 2, 4-D
Answer» C. IAA/X-rays
16.

During cell enlargement phase of growth, molecules of new cell wall material are inserted between the original molecules of stretched wall. This process is known as [DPMT 1980]

A. Intussusception
B. Apposition
C. Integration
D. None of the above
Answer» B. Apposition
17.

Pollen extract stimulates the formation of fruit in the unpollinated carpel because extract has the following hormone [AMU 2005]

A. Auxin
B. Cytokinin
C. Gibberellin
D. Auxin and cytokinin
Answer» B. Cytokinin
18.

Auxin in plant is not means for [BHU 2003]

A. Cell elongation
B. Fruit ripening
C. Cell division
D. Inhibit the root growth
Answer» C. Cell division
19.

Parthenocarpy is induced by [AIIMS 1990; KCET 1994]

A. ABA
B. Auxins
C. Zeatin
D. Cytokinin
Answer» C. Zeatin
20.

The movement of auxin is largely [CBSE PMT 2000]

A. Basipetal
B. Acropetal
C. Centripetal
D. Centrifugal
Answer» B. Acropetal
21.

During germination, stem grows upward and root goes downward because [CPMT 1995]

A. It depends upon light
B. Of auxin
C. It does not depend on light
D. Of epinasty and hyponasty
Answer» C. It does not depend on light
22.

What is the cause of excurrent habit in Pinus [AIIMS 1987]

A. Presence of gibberellin
B. Presence of apical dominance
C. High concentration of cytokinin
D. High concentration of ABA
Answer» C. High concentration of cytokinin
23.

2, 4-D is a [MP PMT 1986, 87; CPMT 1996; BHU 2002; Manipal 2005]

A. Insecticide
B. Weedicide
C. Nematicide
D. Rodenticide
Answer» C. Nematicide
24.

 According to F. Went, auxins transmit

A. From apex to downward
B. Opposite to A
C. From centre to periphery
D. Opposite to C
Answer» B. Opposite to A
25.

Auxins were discovered by [BHU 1988]

A. Thimman
B. Went
C. Butler
D. Skoog
Answer» C. Butler
26.

Most of the information regarding auxins have been obtained from

A. Rice plant
B. Maize grains
C. Avena coleoptile
D. Wheat ear
Answer» D. Wheat ear
27.

Which of the following is not naturally occurring plant hormone  [CPMT 1980, 84, 99; MP PMT 1996; JIPMER 2001]

A. 2, 4-D
B. \[G{{A}_{2}}\]
C. Gibberellin
D. IAA
Answer» B. \[G{{A}_{2}}\]
28.

'Morphactins' are

A. Synthetic growth regulators
B. Synthetic auxins
C. Synthetic gibberellins
D. None of the above
Answer» B. Synthetic auxins
29.

Wound hormone is called

A. Necrohormone
B. Hormone only
C. Auxins
D. Phyllocaline
Answer» B. Hormone only
30.

Abscisic acid (ABA) is a stress related hormone and it also [MHCET 2000]

A. Aids in fruit development
B. Accelerates fruit ripening
C. Stimulates mitosis
D. Mediated stomatal closure
Answer» E.
31.

Which hormone is present in the pulp of fruit, seed coat and resting buds

A. IAA
B. BA
C. GA
D. ABA
Answer» E.
32.

Presence of which of the following in seed is associated with dormancy [DPMT 1982; CBSE PMT 1999; BVP 2002]

A. Starch
B. Abscisic acid
C. Ethylene
D. Gibberellic acid
Answer» C. Ethylene