Unit 5 Biology Essay

1818 Words Nov 12th, 2012 8 Pages
39) Name the specific type of plant tissue or cell that performs the following functions:

a) waterproofing the surface layer

Endodermos

b) rapidly dividing into new cells

Mitosis

c) transporting sugars throughout the plant

Phloem

40)Maple syrup is produces from the sap moving in the xylem of maple trees in the early spring. How would taking too much sap in the spring harm the maple tree?

That sap is an energy store to give it a strong start in spring. If you take too much, that is less energy for the tree to use.

41) A number of plants are currently being stydies for use in cleaning up land sites contanining toxic substances.

a)name the technique of using plants for this purpose

Phytoremediation
…show more content…
IAA, IBA are common auxins. 2,4-D is synthetic auxin when used in higher concentration acts as a weedicide. Mostly used to control Parthenium plants and other dicots.

b) gibberellins

Gibberellins are shoot elongating hormones mostly used to spray on grapes to get a food size and good distribution of the berries on the peduncle.

47) List three factors that are contributing to the decline of pollinator populations.

Possible explanations for pollinator decline 1. Pesticide misuse 2. Rapid transfer of parasites and diseases of pollinator species around the world 3. Loss of habitat and forage 4. Nectar corridors 5. Hive destruction 6. Light pollution 7. Threat by invasive honey bees 8. Air pollution I would probably name pollution and pesticides, predators (destruction) and loss of foraging as the three main factors

48) From an agricultural perspective, describe two advantages of vegetative propagation.

. Only one parent is required which eliminates the need for special mechanisms such as pollination, etc. 2. It is faster. This helps the organisms to increase in number at a rapid rate that balances the loss in number due to various causes.

3. Many plants are able to tide over unfavourable conditions. This is because of the presence of organs of asexual reproduction like the tubers, corm, bulbs, etc. 4. Vegetative propagation is especially beneficial to the agriculturists and horticulturists. They can raise crops

Related Documents