Question

1.) Conduct some research and describe the movement of water and minerals from the tip of the root to the top of the tallest tree. Be sure to start in the soil, describing the relationship of water molecules to soil particles, and end up in the atmosphere (What's the term for the evaporation of water? Be sure to describe the transition from liquid water to gas). The best place to begin is to describe the molecular structure of water, followed by how water moves (Can you say water potential?) Definitely include the name and structure of the cells and tissues the water and minerals will be crossing and transport in (Dont forget the stomates and how they work!)

Answer 1

Water is made up of two H-atoms & one O-atom.It has a mass of 18 Daltons and is a polar molecule.Though electrically neutral,it has a partial positive charge in each H-atom & partial negative charge on each O-atom.

Water potential: defined as the chemical potential of water divided by partial molalal volume of water(the volume of 1 mol of water).It is the measure of the free energy of water per unit volume.

Movement of water:

Water is absorbed into root hairs /epiidermal cells, where root hair makes contact with soil particles & amplify the surface area for water absorption.

Once water is absorbed into root hairs/epidermal cells,it traverses cortex to reach xylem .Transpiraton develops hydroststic tension in xylem of roots which draws water from the soil through intervening tissues to xylem,i.e., epidermis,cortex and endodermis.

2 Pathways through which water moves into xylem:

• Apoplastic movement: water moves into xylem cells through continuous system of cell walls & intercellular spaces.
• Symplastic movement: water moves into xylem cells throgh continuous system of cell protoplasts intermediated by plasmodesmata.

The evaporation creates negative pressure in wlem of leaves which pulls water upward.The water in the xylem is in a state of tension.In this state, negative pressure in xylem water causes cavitation in xylem .However, end walls of vessels & pores prevent the bubble from spreading tube to tube.

Movement of mineral nutrients:

Phloem tissue is made of living elongated cells that are connected to one-another.It is responsible for translocating nutrients & sugars, which are produced by leaves, to plant areas that are metabollically active(requiring sugars for energy and growth).

Cause of opening/closing of stomata id due to change in the turgidity of guard cell.Stomata open because of the osmotic entry of water into guard cell.

Experiment which can be performd is by taking coriander leaves, whiteflowerplant with roots and keep it for a day in a glass containg coloredwater

Observation; colour will change of the flower.

Tranpiration is loss of water from aerial parts of plant in form of water vapour