Describe the action of the stomata to regulate water loss in a plant
What will be an ideal response?
The stomata are surrounded by two guard cells. When the plant is hydrated, and ionic and hormonal conditions are optimal, the guard cells allow potassium ions to enter the guard cells, and water follows by osmosis. This causes the guard cells to swell, and the stoma opens, allowing carbon dioxide to enter the open spaces within the leaf, as carbon dioxide is necessary for photosynthesis. When a plant is water-stressed, the guard cells lose their turgor pressure, as water leaves these cells by osmosis and the stoma close.
You might also like to view...
The middle layer of membranes surrounding the brain and spinal column is the:
a. dura mater. b. meninges. c. arachnoid. d. pia mater.
One of the reasons that most animal cells will not burst if too much water enters by osmosis is that
a. the cell wall will protect it. b. the cytoplasm exerts pressure against the plasma membrane. c. carrier proteins will remove excess water. d. solute molecules will resist water molecules. e. salts will absorb the water.
Which component of amino acids accounts for the differences in their properties?
A) the amino group B) the carboxyl group C) the side group D) the type of bonds
In what order will you encounter the following structures if you examine the human ear from the outside inward?
A. tympanic membrane ? malleus ?incus ? stapes ? cochlea ?oval window B. tympanic membrane ? malleus ?incus ? stapes ? oval window ? cochlea C. tympanic membrane ? oval window ? malleus ?incus ? stapes ? cochlea D. tympanic membrane ? stapes ?malleus ? incus ? oval window ? cochlea E. tympanic membrane ? incus ?malleus ? stapes ? oval window ? cochlea