The correct answers are as follows:
1. A.
There are basically two types of succession, they are primary and secondary succession. Primary succession refers to the type of succession that occurs in new and bare areas where the soil present is unable to sustain the growth of plants. An example of primary succession area is an area with sand dunes that is freshly formed. Primary succession usually occur over a long period of time. Secondary succession is a type of succession that occur on a land which was disturbed by hazardous events such as fire outbreak, flood, etc. Secondary succession occurs much faster than the primary succession.
2. D
There are two types of factors that affect any particular ecosystem, these are abiotic and biotic factors. The abiotic factors refers to non living factors such as temperature, relative humidity, rainfall, etc. while the biotic factors refer to the living factors. Looking at the options given above, one will see that only option D has living factor, which is predators. All other options have abiotic factors.
Answer:
Phagocytosis refers to the engulfing of larger, solid particles. Often, the engulfed particle is another cell, like when a white blood cell, which is a part of the immune system, engulfs a bacterium to destroy it.
Answer:
D. The energy is used by organisms for life functions or is lost as heat.
Explanation:
A holdfast is a root-like structure that anchors aquatic sessile organisms, such as seaweed, other sessile algae, stalked crinoids, benthic cnidarians, and sponges, to the substrate.
This feature of DNA is termed complimentary base pairing, in that the base that compliments a certain base, say A, is always paired with base T, and likewise every T has its pair partner always as A. The same holds true with C with G, and vice versa.