Kerala Plus One Botany Chapter Wise Previous Questions Chapter 7 Transport in Plants
Question 1.
Observe the relationship between the first two and fill in the blanks. (MARCH-2010)
Uniport: The movement of molecules across a membrane independent of other molecules.
Symport : ……………
Antiport : …………
Answer:
Symport
Both molecules cross the membrane in the same direction.
Antiport
Both molecules cross the membrane in the opposite direction.
Question 2.
Mention the concept of fundamental to the understanding of water movement in plants. (MARCH-2010)
Answer:
Water potential
Question 3.
Ramu took equal amounts of water in two glasses and put some sugar in One of them. (SAY-2010)
a) Which one of the glass is having more negative • water potential?
b) Negative water potential in plant cell can cause the physical force concerned with the movement of water molecule. Justify your reasons.
Answer:
a) Sugar solution.
b) Osmosis /diffusion. Water flows from high water potential to lower water potential.
Question 4.
In a classroom experiment teacher placed splitted colacasia petiole one each in two beaker A and B containing different solutions. After 30 minutes the following changes were observed as shown below. By observing the changes identify the solutions and explain the solutions. (SAY-2011)
Answer:
A – Hypertonic solution
B – Hypotonic solution
Hypertonic solution – This is the concentrated solution when compared to the solution of cell sap
Hypotonic solution – This is the less concentrated or dilute solution when compared to the solution of cell sap.
Question 5.
Three potato pieces of equal weight (2 gms) were left in three types of solutions (A, B and C) overnight. The weight change of potato pieces are as shown in the figure. (MARCH-2012)
Before putting in the solution
After putting in the solution
a) Identify the solutions A and C.
b) Discuss the reason for not having any change in the piece put in solution-B.
Answer:
a) A – Solution Hypertonic
C – Solution – Hypotonic
b) B – Solution – Isotonic. The Osmotic pressure of the external solution and cell sap are same. Hence no net flow of water towards inside or outside of potato pieces.
Question 6.
Suggest reason for the following : (SAY-2012)
a) In tomato plants drops of water are seen along leaf margins in the morning.
b) Farmers remove leaves of banana plants before planting.
Answer:
a) Guttation
b) To reduce transpiration or to check water loss.
Question 7.
‘Unlike water, all minirals cannot be passively absorbed by roots’. Write any two reasons to justify the above statement.(MARCH-2013)
Answer:
- Minerals in the soil present as charged particles
- Concentration of mineral is lower than that in the root
Question 8.
Proteins in the membrane are responsible for facilitated diffusion and active transport and hence both show common characteristics. List any two such characteristics. (MARCH-2013)
Answer:
- Both are highly selective
- Liable to saturate
Question 9.
Match the following: (SAY-2013)
Answer:
Apoplast – cell wall
b) Transpiration – stomata
c) Mass flow hypothesis – phloem transport
d) Osmosis – Semipermeable membrane
Question 10.
Transpiration has more than one purpose in plants. Write any one purpose of transpiration in plants and list any two factors that affect this process. (MARCH-2015)
Answer:
- It supply water for photosynthesis
- Transport minerals from soil to all part of the plant Temperature and humidity
Question 11.
Define imbibition and give one example studied by you. (SAY-2015)
Answer:
Certain hydrophilic colloids absorb water but without forming solution, it is called imbibition.
Eg – Dry seeds absorb water and swells up
Question 12.
How can you differentiate active transport from facilitated diffusion? (MARCH-2016 )
Answer:
In active transport, transport proteins and energy are used In facilitated diffusion- transport protein only is used.
Question 13.
Observe the diagram and identify the phenomenon that helps in the transport of molecules in plants. Also mention the three type of movement of molecules shwon in the diagram as (i), (ii) and (iii). (SAY-2016)
Answer:
Facilitated diffusion
i) Uniport
ii) Antiport
iii) Symport
Question 14.
The movement of water through the root layers is ultimately symplastic in the endodermis. Give a reason. (MARCH-2017)
Answer:
In endodermal walls suberin is present, so it is thickened called casperian thickening . it prevent the flow of water through wall layers hence the apoplastic pathway is blocked and further transport takes place in symplastic pathway.