Question

( answer all questions )

1. Which one of these describes the ecological relationship called symbiosis?

A. corals are large, complex structures built by tiny organisms and consist of their 'shells' and themselves. Some corals' animals are photosynthetic--they house single- celled photosynthetic microorganisms that provide the animal with sugars and other nutrients. The coral animals' bodies give the photosynthetic microbes a sheltered, chemically stable location and provide fresh (not salt) water

B. A fully mature flower is ready to have its pollen spread to other plants of the same kind. A bee lands on the flower, reaches deep into it and drinks sweet nectar. It climbs back out of the flower and, just as it occurred when the bee entered the flower, the hairs on the bee's back and the 'pollen combs' on its hind legs, capture a large amount of pollen. This will end up on the next flower's female structures--this is pollination. The bee and the plant live separate, independent lives

C. mistletoe, a plant that grows as a thick bunch on the branches of trees, penetrates the surface of the branch with special sucking structures that remove water and nutrients from the tree's vascular system

2. Which one of these descriptions of fungi is correct?

A. fungi gain nutrients from decomposing dead animals

B.some fungi grow underground, forming large white masses made up of tangled fungal filaments

C. fungal hyphae are made up of long chains of plant cells

3. Why doesn't chaparral soil contain much decomposed organic material?

A. the plants drop few or no leaves

B. there are no decomposers living in chaparral soil

C. chaparral soil does not have a steady, consistent water content; it is too dry for the organisms that break down (decompose) dead plant material

4. How do fungi spread through soil?

A. very quickly

B. by hyphal extension (i.e., as hyphae grow due to cell division)

C. fungal cells do not move

Answer 1

1) Option A and B shows symbiosis. Symbiosis is a relation in which two different species give benefits to each other. In option A corals animals and unciellular microorganism both are giving benefits to each other. Same way in option B Flower provides nector and bee helps in pollination so both helping each other.

2) Option A and B are correct. Fungi are saprophytes i.e. they feed on dead organic matter to gain nutrients. Some fungi grow undergroound forming large white masses made up of tangled fungal filaments (mycelium).

Fungal cell wall is made up of chitin while plant cell wall is cellulosic so fungal hyphae can not made up of plant cells.

3) Option C is correct. Chaparral soil is too dry for the organisms to break down dead plants material.

4) Fungal hyphae do not grow due to cell division but by the expanision at hyphal tip due to hydrostatic pressure (Turgor pressure). Fungal cells do not move. So option C is correct.