Which of the following facilitates opening of stomatal aperture :-

(1) Contraction of outer wall of guard cells

(2) Decrease in turgidity of guard cells

(3) Radial orientation of cellulose microfibrils in the cell wall of guard cells

(4) Longitudinal orientation of cellulose microfibrils in the cell wall of guard cells

Subtopic:  Stomata: 3 | Stomata |
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NEET 2021 - Achiever Batch - Aryan Raj Singh
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A few drops of sap were collected by cutting across a plant stem by a suitable method. The sap was tested chemically. Which one of the following test results indicates that it is phloem sap?

(1) Acidic

(2) Alkaline

(3) Low refractive index

(4) The absence of sugar

Subtopic:  Ascent of Sap |
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Root pressure develops due to

1. active absorption

2. low osmotic potential in soil

3. passive absorption

4. increase in transpiration

Subtopic:  Radial Transport |
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NEET 2021 - Achiever Batch - Aryan Raj Singh
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A column of water within xylem vessels of tall trees does not break under its weight

because of

1. dissolved sugars in water

2. tensile strength of water

3. lignification of xylem vessels

4. positive root pressure

Subtopic:  Transpiration Pull: Illustration |
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NEET 2021 - Achiever Batch - Aryan Raj Singh
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Transpiration and root pressure cause water to rise in plants by

1. Pulling it upward

2. pulling and pushing it, respectively

3. pushing it upward

4. pushing and pulling it, respectively

Subtopic:  Transpiration & Guttation |
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In a ring girdled plant ?

1. the shoot dies first

2. the root dies first

3. the shoot and root die together

4. Neither root nor shoot will die

Subtopic:  Phloem Translocation |
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Which one gives the most valid and recent explanation for stomatal movements?

1. Transpiration

2. Potassium influx and efflux

3. Starch hydrolysis

4. Guard cell photosynthesis

Subtopic:  Stomata: 3 | Stomata |
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Which of the following criteria does not pertain to facilitated transport?

1. Requirement of special membrane proteins

2. High selectivity

3. Transport saturation

4. Uphill transport

Subtopic:  Means of Transport: Passive |
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Which one of the following elements in plants is not remobilised?

1. Calcium

2. Potassium

3. Sulphur

4. Phosphorus

Subtopic:  Phloem Translocation | Photosynthesis Transpiration Compromise & Mineral Translocation |
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NEET 2021 - Achiever Batch - Aryan Raj Singh
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The rupture and fractionation do not usually occur in the water column in vessel/tracheids during the ascent of sap because of

1. lignified thick walls

2. cohesion and adhesion

3. weak gravitational pull

4. transpiration pull

Subtopic:  Transpiration & Guttation | Transpiration Pull: Illustration |
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