Tag: ascent of sap

Questions Related to ascent of sap

Ascent of sap is best explained by.

botany water absorption and ascent of sap in plants factors affecting the transport of water and minerals in plants ascent of sap long distance transport of water

  1. Mass (bulk) flow

  2. Pulsation theory

  3. Root pressure

  4. Cohesion-tension transpiration pull

Show answer
Correct Option: D
Explanation:

The cohesion-tension theory is a theory of intermolecular attraction that explains the process of water flow upwards (against the force of gravity) through the xylem of plants. Transpiration pull, utilizing capillary action and the inherent surface tension of water, is the primary mechanism of water movement in plants.
Answer is D.

the major driving force in the movement of water in the xylem is 

botany water absorption and ascent of sap in plants factors affecting the transport of water and minerals in plants ascent of sap long distance transport of water

  1. Osmotic pressure

  2. gravitational pull

  3. transpiration pull

  4. Diffussion pressure

Show answer
Correct Option: C
Explanation:
The movement of water in the xylem is explained by the cohesion-tension theory. According to this theory, the water moves up in the xylem via the force of transpiration which is created because of the evaporation of water from the leaves of the plant.

So, the correct answer is 'transpiration pull'.

Read the following statements regarding transaction and select the correct option
I. Transpiration is the loss liquid droplets from the plant
II. Low atmospheric pressure inhibits transpiration
III. Transpiration maintains the shape and structure of plant parts
IV. Cuticular transpiration takes place only during day time

botany water absorption and ascent of sap in plants factors affecting the transport of water and minerals in plants ascent of sap long distance transport of water

  1. I &II only

  2. I, II &III only

  3. III only

  4. None of the statements are true

Show answer
Correct Option: D
Explanation:
  • The process of loss of water from the aerial part of the plant in the form of vapor is known as transpiration.
  • It is of three types:-
(i) Cuticle transpiration (loss of water from cuticles),
(ii)Lenticular transpiration (loss of water from lenticels)
(iii)Stomatal transpiration (loss of water from stomata)
  •  Atmospheric pressure, humidity, and temperature are some factor that affects transpiration.
So, the correct option is 'None of the statements are true'.

Which of the following sequence is completely cryptoanalysed?

botany water absorption and ascent of sap in plants factors affecting the transport of water and minerals in plants ascent of sap long distance transport of water

  1. AUG UCG GAG UAA UUU UGA

  2. AUG UUG UGG GAG UCA UAG

  3. GUG UCG UGA AAG UAU UGA

  4. AUG AAU GCU GUT UAC UAA

Show answer
Correct Option: D
Explanation:

The sequence that can be cryptoanalyzed/ all the codons code for proteins will be devoid of any stop codons. 

Since all the other sequences except AUG AAU GCU GUT UAC UAA can code for proteins without intermediate termination, it can be completely cryptoanalyzed.
So, the correct option is 'AUG AAU GCU GUT UAC UAA'.

Read the following statements and identify the incorrect difference between transpiration pull and root pressure.

Transpiration pull Root pressure
$(1)$ Acts as main driving force for translocation of water in tall trees It establishes chain of water molecules in xylem of tall trees
$(2)$ Its magnitude is maximum during day time Its magnitude is maximum during early morning and night
$(3)$ It generates a strong positive water potential in xylem It is a negative hydrostatic pressure developed in xylem
$(4)$ It is manifestation of passive water absorption It generates from active water absorption
botany water absorption and ascent of sap in plants factors affecting the transport of water and minerals in plants ascent of sap long distance transport of water

  1. $1$

  2. $2$

  3. $3$

  4. $4$

Show answer
Correct Option: A

A pressure that is responsible for pushing up water to small height in the stem is?

botany water absorption and ascent of sap in plants factors affecting the transport of water and minerals in plants ascent of sap long distance transport of water

  1. Positive root pressure

  2. Turgor pressure

  3. Pressure gradient

  4. Negative root pressure

Show answer
Correct Option: A

Match the columns.

Column I Column II
A. Semipermeable membrane $1$. Dixon and Jolly
B. Transpiration pull $2$. Manometer
C. Pulsation theory $3$. Holard
D. Root pressure $4$. JC Bose
E. Whole water content in soil $5$. Osmosis
botany water absorption and ascent of sap in plants factors affecting the transport of water and minerals in plants ascent of sap long distance transport of water

  1. A-$2$, B-$1$, C-$4$, D-$5$, E-$3$, F-$1$

  2. A-$5$, B-$1$, C-$4$, D-$2$, E-$3$, F-$1$

  3. A-$5$, B-$4$, C-$1$, D-$2$, E-$3$, F-$1$

  4. A-$1$, B-$1$, C-$2$, D-$4$, E-$3$, F-$5$

Show answer
Correct Option: A

Who gave the imbibition theory of ascent of sap

botany water absorption and ascent of sap in plants factors affecting the transport of water and minerals in plants ascent of sap long distance transport of water

  1. Unger

  2. Dixon and Joly

  3. Bose

  4. Godlewski

Show answer
Correct Option: A

Which of the plants can absorb water in the form of vapour from its atmosphere?

botany water absorption and ascent of sap in plants factors affecting the transport of water and minerals in plants ascent of sap long distance transport of water

  1. All xerophytes

  2. Low transpiring cacti

  3. Succulent plants

  4. Epiphytes and lichen

Show answer
Correct Option: D
Explanation:

Epiphytes are the plants growing on other plants. They have hanging roots having velamen tissue, which can directly absorb moisture from atmosphere. 

Lichens are not plants but symbiotic associations between fungi and algae. They do not have well developed roots but the thallus making up their body can directly absorb moisture from atmosphere.

Attractive forces of cell walls for water molecules is termed as

botany water absorption and ascent of sap in plants factors affecting the transport of water and minerals in plants ascent of sap long distance transport of water

  1. Adhesion

  2. Cohesion

  3. Osmosis

  4. Plasmolysis

Show answer
Correct Option: A
Explanation:

Adhesion is the tendency of dissimilar particles or surfaces to cling to one another. Attractive forces of cell walls for water molecules is termed as adhesion. The continuous column of water is maintained by cohesion forces between water molecules and adhesive forces between water molecules and cell walls of vascular elements of the plant.