Which of the following is used to classify organisms into the Kingdom Fungi?

Question

a. Ability to photosynthesize; possess a call wall

b. Unicellular; possess cell wall; prokaryotic

c. Unicellular; lacking cell wall; eukaryotic

d. absorptive; possess cell wall; eukaryotic

e. Ingestive; lacking cell wall; multicellular; prokaryotic

Answer 1

d.

Fungi are typically multicellular (some grow as single cells) eukaryotes (ruling out b., c. and e.) that possess cell walls (ruling out c & e.), but do not photosynthesize (ruling out a.) -- they're actually more closely related to animals than plants. By "absorptive" I assume you mean heterotrophic? Presumably yes, so d. it is.

Read more here: http://en.wikipedia.org/wiki/Fungi

Answer 2

There are over two million different living organisms in  the world today which must be sorted into groups to aid our study of them. In dealing with diversity, classification is essential for efficient thought. Until quite recently, living organisms were divided into two kingdoms, the animal kingdom and the plant kingdom. The animal kingdom contained mainly motile organisms which fed heterotrophically, and the plant kingdom contained mainly static organisms which fed autotrophically by photosynthesis. Fungi were regarded as plants since they have a cell wall and are immotile. With only two kingdoms however, certain organisms such as protozoa could, in effect, jump from one kingdom to the other! It was not until 1866 that this classification system was altered. Haeckel, a follower of Darwin, postulated a third kingdom - the protista. This kingdom was to contain all microscopic organisms, including bacteria, protozoa and fungi. With the advent of the electron microscope in the 1950s, the basic differences between bacteria and other organisms became visible. Two domains were thus created; bacteria, with their lack of a distinct nucleus, led to their separation into the prokaryote domain; and the eukaryote domain which housed all other organisms.

In 1969, an American biologist, Whittaker, recognised that fungi are different from other eukaryotes in many essential aspects, so he designated them to a new kingdom. Whittaker's clarification of the system attempted to place organisms in kingdoms that more nearly resembled their supposed evolutionary relationships. This five kingdom approach to classifying organisms was an important step in the attempt to form groups that contain an ancestor and all its descendants (monophyletic groups) and to create a system where similarities and relationships may be seen. It had long been accepted that evolution had occurred since the publication of The Origin of Species (Darwin, 1859); where present species had evolved from earlier species and where similar species had a recent common ancestor, different species a more distant one. Thus a natural classification should mirror descent.

Whittaker noticed, for example, the methods of nutrient intake for the three main eukaryote kingdoms (Animals, plants and fungi) were completely different. Animals absorb nutrients internally, engulfing food by the action of ingestion. Plants too have a form of internal absorption, with the intake of energy from the sun by photosynthetic organelles (Chloroplasts). Fungi, however, are the only eukaryote who have to externally digest their food component  prior to absorption. Characteristically, fungi dwell in a food source absorbing nutrients from the medium, and in many instances releasing digestive enzymes for external digestion.

In the last 30 years, recent advancements in technology, including DNA sequencing techniques, have placed a severe strain on Whittaker's five-kingdom system. At present, the dispute of the number of kingdoms required to classify all living and fossil taxa still is not concluded. Kingdoms are really the trunk and major branches of an evolutionary tree. Splitting the tree into kingdoms is an arbitrary process and depends whereabouts along the trunk and branches you make your cut. The higher you cut, the more kingdoms you will get. In fact some of the classification schemes which have been brought forward contain more than 15 kingdoms! A five-kingdom system of life has a charming simplicity. Unfortunately, throughout evolution, many losses and births of complex characters entangle this system. Therefore, down to molecular sequencing in particular, a six-kingdom system now seems necessary to enable us to place organisms in a fairer and more defined phylogenetic classification.