Discovery of Auxin

Q. The PGRs which play an important role in plant responses to wound and stresses of biotic and abiotic origin and also involved in various growth inhibiting activities such as dormancy and abscission is/are

Q.

Which plant hormone was first isolated from human urine?

Q.

What is a coleoptile in plants?

Q.

Identify the set of natural auxins (A) and synthetic auxins (B) from the following.

1. 2, 4 - B

2 .NAA

3. 4-chloro AA

4.PAA

5.2, 4, 5-T

6. IBA

7. IAA

1. A - 1 , 2, 3&4 B - 5 , 6&7

2. A - 4 , 6&7 B - 2 , 5, 3 &1

3. A - 7, 3&4 B - 1 , 2 & 6

4. A - 1 , 5, 7&3 B - 2 , 4 & 6

Q.

Can aspirin be used as a rooting hormone?

Q. Scientists who isolated auxins from the coleoptiles of Avena and from human urine are _________ respectively.

1. Went and Darwin

2. Went and Kogl

3. Boysen -Jensen and Paul

4. Kogl and Smith

Q. Which of the following prevents the fall of fruits?

1. NAA
2. Zeatin
3. Ethylene
4. $G{A}_3$

Q. $\alpha -$amylase activity test in barley endosperm is bioassay of :

1. Cytokinin
2. Auxin
3. $\text{ABA}$
4. Gibberellin

Q. The auxin 2, 4, 5-T is

1. phenoxy acid
2. benzoic acid
3. naphthalenic acid
4. indole auxin

Q.

Which one among the following is needed for tissue culture?

1. Kinetin

2. Coumarine

3. Trypsin

4. Caffine

Q. Which of the following is an auxin?

1. Indole acetic acid
2. Malic acid
3. Abscisic acid
4. Pyruvic acid

Q.

"Avena curvature test" is an example of

1. Bioassay

2. Biotechnology

3. None of these

4. Tissue culture

Q. To prevent the damage of newly formed cells, part of the cultures are regularly transferred to new culture vessels containing fresh media. this process is termed as

1. Callus culture
2. Subculturing
3. Suspension culture
4. Hardening

Q. Very short answer type.
Name two synthetic auxins used in agriculture.

Q. Which of the following is not a natural auxin?

1. Indole acetic acid
2. Naphthalene acetic acid
3. Indole acetaldehyde
4. Indole ethanol

Q. The velocity of enzymatic reaction increases with the.......... in substrate concentration up to a certain point until it approaches the maximum value

Q. Select the activities associated with gibberellins.
$\left(a\right)$ Apical dominance
$\left(b\right)$ Good herbicides
$\left(c\right)$ Promote bolting
$\left(d\right)$ Delay senescence
$\left(e\right)$ Stimulate closure of stomata.

1. $a$ and $b$ only
2. $b$ and $d$ only
3. $a$, $c$ and $d$ only
4. $b$ and $c$ only
5. $c$ and $d$ only

Q. Assertion :The first phytohormone to be discovered was auxin. Reason: Light reaction of coleoptile tip attracted the attention of Darwin in the last quarter of nineteenth century.

1. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
2. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
3. Assertion is correct but Reason is incorrect
4. Both Assertion and Reason are incorrect

Q. Plant growth hormones extracted from a fungus and a fish are respectively

1. Gibberellins and zeatin
2. Ethylene and cytokinin
3. Auxin and 2, 4-D
4. Gibberellin and kinetin

Q. Match the columns and find the correct option.

(a) Munch	(i) Stomatal movement
(b) Darwin	(ii) Hastens fruit ripening by volatiles
(c) Cousins	(iii) Growth of coleo towards light
(d) Levitt	(iv) Nature of enzymes
	(v) Bidirectional traces in phloem

1. a- iii, b- i, c- iv, d- v
2. a- v, b- iii, c- ii, d- i
3. a- iv, b- iii, c- i, d- ii
4. a- iii, b- iv, c- i, d- ii

Q. A mutant strain of Neuraspora which fails to grow on a minimal medium unless supplemented with a nutrient is called

1. Auxotroph
2. Autotroph
3. Prototroph
4. Heterotroph

Q. Scientists who isolated auxins from the coleoptiles of Avena and from human urine are _________ respectively.

1. Went and Darwin
2. Went and Kogl
3. Boysen-Jensen and Paul
4. Kogl and Smith

Q. Why the study/checking chemical and physical properties of daily used substances/ material is essential?

Q. Which plant hormone is basic in nature?

1. Gibberellin
2. Auxin
3. Ethylene
4. Cytokinin

Q.

Avena curvature test is a bioassay for examining the activity of

1. Auxins

2. Gibberellins

3. Ethylene

4. Cytokinins

Q. Allograft is not rejected, in case of identical twins because?

1. Identical twins have similar immune system
2. Identical twins have same blood group
3. Human leukocyte antigens on WBC's are identical
4. Human leukocyte antibodies on WBC's are identical

Q. Select the correctly matched pair.

1. Darwin and Darwin - Gibberellic acid
2. Bentham- Auxin
3. Kurosawa - Ethylene
4. Skoog and Miller - Abscisic acid
5. Cousins - Cytokinin

Q.

Avena curvature test is a bioassay for examining the activity of

1. Auxins

2. Cytokinins

3. Ethylene

4. Gibberellins

Q. Kautsky effect is

1. Photoluminescence in the absence of photosynthesis
2. Outburst of fluorescence at the end of illumination
3. Outburst of fluorescence during first few moments of illumination
4. Bioluminescence at night

Q. Who speculated for the first time the presence of organ forming substances in the plant now called as hormones?

1. Darwin
2. Went
3. Sachs
4. Yabuta