Tag: theories of translocation

Questions Related to theories of translocation

By many evidences, it can be known that the downward movement of food takes place through

  1. Phloem

  2. Xylem

  3. Collenchyma

  4. Sclerenchyma


Correct Option: A
Explanation:

Movement of food takes place through phloem tissue. This can be demonstrated through ringing experiment in which, if ring of vascular tissue including phloem is removed in a dicot tree. The plant parts located below the point of ringing will die because these parts do not get food.

Thus, the correct answer is option A.

How many of the following features are related to Dixon and Jolly model of water transport in plants?
a. Cohesion between water molecules
b. Transpiration pull
c. Pushing of water by negative root pressure
d. Surface tension
e. Pushing of water by positive root pressure.

  1. $4$

  2. $5$

  3. $2$

  4. $3$


Correct Option: A

Bulk flow or mass flow.

  1. Can be achieved through root pressure

  2. Can be achieved through transpiration pull

  3. Can be achieved either through a positive Hydrostatic pressure or a negative hydrostatic pressure

  4. More than one option is correct


Correct Option: A

The major source of minerals in the soil is

  1. Parent rock from which soil is formed

  2. Plants

  3. Animals

  4. Decomposers


Correct Option: A
Explanation:

The absorption, distribution and metabolism of various mineral elements by plants are called mineral nutrition. The mineral elements play important role in the performance and maintenance of life activities. All microelements are absorbed by plants in traces and derived from the parent rock by the process of weathering. 

So, the correct answer is option A.

Nutrient which are required in small quantities are called as

  1. Macronutrients

  2. Micronutrients

  3. Primary nutrients

  4. None of the above


Correct Option: B
Explanation:

A nutrient which is required in small quantities is called as a micronutrient. The micronutrients are boron, chlorine, copper, iron, manganese, molybdenum and zinc. These plant food elements are used in very small amounts, but they are just as important to plant development and profitable crop production as the major nutrients. Especially, they work "behind the scene" as activators of many plant functions.

Thus, the correct answer is 'Micronutrients'.

Ammonium sulphate is a

  1. Pesticide

  2. Weedicide

  3. Fertilizer

  4. Tonic chemical


Correct Option: C
Explanation:

Ammonium sulfate is a fertilizer as it increases the fertility of soil and plants can use it for their functions.

It cannot kill pests or weeds and hence is not a pesticide or a weedicide.
Tonic chemicals are medicines given to feel vigour. Ammonium sulfate has no such function.
So the correct answer is 'Fertilizer'.

Active transport of ions by the cell requires

  1. High temperature

  2. ATP

  3. Alkaline pH

  4. Salts


Correct Option: B
Explanation:

Whenever active transport is being carried out energy is required and ATP is used up as it is the energy currency of the cell.

High temperature, Alkaline pH or Salts cannot carry out active transport as it involves movement of a substance against it's concentration gradient.
So, the correct answer is 'ATP'

Active transport from outside to inside of molecules across a membrane requires

  1. Cyclic AMP

  2. ATP

  3. Phloroglucinol

  4. Acetyle chloine


Correct Option: B
Explanation:

The active transport of substances require energy and hence they use up ATP which is the energy currency of the cell.

Acetly choline and Cyclic AMP are involved in cell signalled.
Phloroglucinol is a stain used to observe lignin.
So the correct answer is 'ATP'.

Select the correct statement regarding "A trace element is an element which".

  1. Is a radio active and can be traced by Geiger counter.

  2. Is required in very minute amounts.

  3. Draws other element out of protoplasm.

  4. Was one of the first to be discovered in protoplasm.


Correct Option: B
Explanation:

Trace elements are the ones which are required in. Very less amount and are present in less amounts as compared to other elements of major use.

Usually, they have very specific functions and do not contribute structurally.
Macronutrients were discovered first in the cytoplasm.
Radioactive elements are usually not present in the plant bodies.
So the correct answer is 'Is required in very minute amounts'.

In the root nodules of legumes, leghaemoglobin is important because it

  1. Transports oxygen to the root nodule.

  2. Acts as an oxygen scavenger.

  3. Provides energy to the nitrogen fixing bacterium.

  4. Acts as a catalyst in transamination.


Correct Option: B
Explanation:

The root nodule bacterium is microaerobic in the sense that it requires oxygen but the high concentration of oxygen is detrimental to nitrogen-fixing enzyme system. Here leghaemoglobin proves beneficial, it absorbs or binds oxygen so that there is no free oxygen left in the nodule and then carries micro-amounts of oxygen to the nodule bacteroids. Thus the correct answer is option B.