Tag: transport of food, water and minerals

Quizzes (0) Questions (48)

Questions Related to transport of food, water and minerals

Multiple choice biology transport in plants transport of food, water and minerals theories of translocation transport in the phloem of plants

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.
Reveal answer Fill a bubble to check yourself
B Correct answer
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'.

Multiple choice biology transport in plants transport of food, water and minerals theories of translocation transport in the phloem of plants

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.
Reveal answer Fill a bubble to check yourself
B Correct answer
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.

Multiple choice biology transport in plants transport of food, water and minerals theories of translocation transport in the phloem of plants

Brown heart disease is due to the deficiency of

  1. Boron.

  2. Iron.

  3. Molybdenum.

  4. Phosphorus.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Boron regulates pentose phosphate pathway, increases sugar translocation in plants. Due to deficiency of boron growth of roots stops and the disease ' brown heart' is caused in sugarbeet. Thus option A is the correct answer.

Multiple choice biology transport in plants transport of food, water and minerals theories of translocation transport in the phloem of plants

Which hypothesis states that root absorbs a large quantity of ions along with absorption of water due to transpiration?

  1. Donnan equilibrium hypothesis

  2. Ion exchange hypothesis

  3. Mass flow hypothesis

  4. Kranz's hypothesis
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The Pressure flow hypothesis often regarded as mass flow hypothesis explains best about the movement of Plant sap through phloem .The concept was proposed by E.Munch . The transpiration of water from leaves and other part of plant body produces negative pressure inside transport vessels causing root to absorb large amount of water along with ions to maintain the continuity of column of water . 

So, correct Option is Option C.

Multiple choice biology transport in plants transport of food, water and minerals theories of translocation transport in the phloem of plants

Which of the following is not involved in the phenomenon called ion exchange?

  1. $Negatively\quad charged\quad clay\quad particles$
  2. $pH$
  3. $Cations\quad like\quad K^+, Mg^{2+}, and\quad Ca^{2+}$
  4. $H _2S$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
Ion exchange processes are reversible chemical reactions for removing dissolved ions from solution and replacing them with other similarly charged ions. Negatively charged clay particles are removed using cations like K$^{+}$, Mg$^{+}$ and Ca$^{+}$.
Ion-exchange chromatography separates biomolecules based on differences in their net charge at a particular pH. 
So, the correct option is 'H$ _2$S'
Multiple choice biology transport in plants transport of food, water and minerals theories of translocation transport in the phloem of plants

Plants absorb minerals salts from the soil solution through

  1. A semipermeable membrane into the cytoplasm

  2. Perforations at the apex of root hair cells

  3. The cell wall which is semipermeable

  4. None of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The mineral salts are absorbed into the symplasm, i.e., cytoplasm of root cells. There are special specific mineral transporters present in the plasma membrane of cells, which absorb the minerals from soil solution by transporting them across the membrane from soil solution to the cytoplasm of root cells. This way minerals can be absorbed irrespective of or against the concentration gradient of minerals. The minerals are present in the soil solution at very low concentrations and are usually absorbed against the concentration gradient with the help of specific carriers.

Multiple choice biology transport in plants transport of food, water and minerals theories of translocation transport in the phloem of plants

Identify the theory of passive absorption of mineral salts.

  1. Carrier concept

  2. Cytochrome pump theory

  3. Carbonic acid exchange theory

  4. None of the above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The roots respire continuously giving out carbon dioxide into the rhizosphere. Carbon dioxide combines with water and forms carbonic acid. Carbonic acid dissociates into  H$^+$ and HCO$ _3$$^-$. Because of high respiratory activity, a zone of carbonic acid is developed in root tips. The H$^+$ ions are exchanged with cations adsorbed on the clay micelle. The cations then come into the soil and diffuse onto the root surface. This is the carbonic acid exchange theory. Thus the correct answer is option C.

Multiple choice biology transport in plants transport of food, water and minerals theories of translocation transport in the phloem of plants

During respiration in plant root, carbonic acid is formed in the

  1. Root cells.

  2. Intercellular space.

  3. Soil.

  4. None of the above.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Soil respiration refers to the production of carbon dioxide when soil organisms respire. They include roots and other microbiota. Roots continuously respire and liberate significant quantities of CO2. The CO2, when dissolved in soil water, produces carbonic acid.  Immediately they ionize into H+ and bicarbonate ions. Thus during respiration in plant root carbonic acid is formed. Thus the correct answer is option C.

Multiple choice biology transport in plants transport of food, water and minerals theories of translocation transport in the phloem of plants

The theory of transfer of ions from soil to root without passing into solution was given by

  1. Jenny.

  2. Oversheet.

  3. Donnan.

  4. Both A and B.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

According to the theory of ions put forth by Jenny and Overstreet, ions are transferred from soil to root or vice versa without passing into solution. The ions are electrostatically adsorbed to the surface of root cells and are held tightly. These ions oscillate within a small volume of space called oscillation volume. When the oscillation volume of two ions of same charge overlap one ion is exchanged for the other. This is called contact exchange. Thus the transfer of ions from soil to root takes place without passing into solution. Thus the correct answer is option D.