TRANSPORT IN PLANTS
1. Observe the relationship between the first two and fill in the blanks (1)Uniport: The movement of molecules across a membrane independent of the other molecules.
2. Mention the concept of fundamental to the understanding of water movement in plants. (1)
1. Ramu took equal amounts of water in two glasses and put some sugar in one of them. (2)
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 movement of water molecule. Justify your reasons.
1. In most woody trees, epidermis breaks to form a lens shaped opening. Name this opening that permits gaseous exchange. (1)
2. In the early morning, droplets of water can be found at the tip of grass leaves, name the phenomenon. Can you give an explanation for this phenomenon? (2)
2011 October (Improvement)
1. During sunny days grass leaves curl inwards and minimize water loss. Why? Name the cells responsible for the curling. (1)
2. In a class room 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. (2)
1. 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.
Before putting in the solution After putting in the solution
a. Identify the solutions A and C (½ + ½)
b. Discuss the reason for not having any change in the piece put in solution B. (1)
2012 September (Improvement)
1. Suggest the reason for the following: (2)
a. In tomato plants drops of water are seen along leaf margins in the morning.
b. Farmers remove leaves of banana plants before planting.
1. ‘Unlike water, all minerals cannot be passively absorbed by roots’. Write any two reasons to justify the above statement. (2)
2. Proteins in the membrane are responsible for facilitated diffusion and active transport and hence both show common characteristics. List any two such characteristics. (2)
2013 September-October (Improvement)
1. Match the following: (2)
c. Mass flow hypothesis
1. Normally, roots grow into the soil. But in some plants like Rhizophora, many roots come out of the ground and grow vertically upwards. What are these roots called? Give their function. (½ + ½ = 1)
2014 August (Improvement)
1. Stomata are small openings present in the epidermis of leaves. The stomata are bound by guard cells. Mention the role of guard cells in stomatal mechanisms. (2)
1. In most of the plants, roots are meant for absorption and fixation. But there are exceptions to these functions.
Justify the statement citing at least three examples. (3)
The main function of most of the stems is spreading out branches, bearing leaves, flowers and fruits and the conduction of materials. But there are exceptions to this. Justify the statement citing at least three examples.
2015 September (Improvement)
1. Define imbibition and give one example studied by you. (2)
1. How can you differentiate active transport from facilitated diffusion? (2)
1. The movement of water through the root layers is ultimately symplastic in the endodermis. Give a reason. (2)
2017 July (Improvement)
1. A cell when placed in n. concentrated sucrose solution, shrink after few hours. Identify the physical phenomenon that leads to shrinkage of cell and justify your answer. (2)
1. State any four features of facilitated diffusion.