Moulds, those dusty little spots often found spreading over bread, cheese, books, and other things in the home, cause the loss of millions of dollars to our economy every year and, even worse, may be a menace to your health. To deal with them successfully we must understand what moulds are and exactly what they are doing.
Moulds are microscopic, plant-like organisms, composed of long filaments called hyphae. Mould hyphae grow over the surface and inside nearly all substances of plant or animal origin. Because of their filamentous construction and consistent lack of chlorophyll they are considered by most biologists to be separate from the plant kingdom and members of the kingdom of fungi. They are related to the familiar mushrooms and toadstools,differing only in not having their filaments united into large fruiting structures. For our purposes here, we shall consider as moulds only fungi that are commonly encountered n the home and laboratory and that can be easily grown and studied.
When mould hyphae are numerous enough to be seen by the naked eye they form a cottony mass called a mycelium. It is the hyphae and resulting mycelia that invade things in our homes and cause them to decay.
Reproduction in fungi is complex and involves a great diversity of structures. At the most fundamental level we can say that most moulds reproduce by spores. Spores are like seeds; they germinate to produce a new mould colony when they land in a suitable place. Unlike seeds, they are very simple in structure and never contain an embryo or any sort of preformed offspring. Spores are produced in a variety of ways and occur in a bewildering array of shapes and sizes. In spite of this diversity, spores are quite constant in shape, size, colour and form for any given mould, and are thus very useful for mould identification.
The most basic difference between spores lies in their method of initiation, which can be either sexual or asexual. Sexually initiated spores result from a mating between two different organisms or hyphae, whereas asexual spores result from a simple internal division or external modification of an individual hypha. the recognition of a mating and subsequent spore formation is often difficult for an observer,and is usually reserved for patient specialists. However, for practical purposes one can learn to recognize certain indications of the sexual process, namely, the four kinds of sexually determined spores that appear in mould fungi: (1) oospores, (2) zygospores, (3) ascospores, and (4) basidiospores.
We can easily move the box from a ground floor though to the first floor at an angle of 40° to the horizontal by simply pushing the load through an inclined plane. We will simply be lean the inclined plane on the building at the required angle and the push through the the height of the building.
Based on the explanation above, the best type of simple machine to use is an INCLINED PLANE. <em>Note that the essence of using a machine is simply to make our work easier and faster and also be able to overcome a much larger load with a minimal effort. </em>
Volcanic degassing of volatiles, including water vapour, occurred during the early stages of crustal formation and gave rise to the atmosphere. When the surface of Earth had cooled to below 100 °C (212 °F), the hot water vapour in the atmosphere would have condensed to form the early oceans.
Mendel wants to control the pollination of his pea plants because traits were not blended but they remain separate in the subsequent generations and also it is contrary to scientific opinion during his time
<u>Explanation:</u>
Mainly, he wants to control because they were against the scientific opinion during his time.
Mendel takes a pea plant for his experiment because it can be easily observable.
Pea plant has seven traits and it can be pollinated by both the ways. One is self-pollination and the other is cross-pollination.
Mendel did not know about the genes but he speculates the factors of formation in the traits.
Mendel produces three laws, the law of dominance, the law of segregation, the law of independent assortment.
