DNA, cell membrane, cytoplasm, and ribosomes.
Both prokaryotic and eukaryotic cells have structures in common. All cells have a cell membrane, ribosomes, cytoplasm, and DNA. The cell membrane, or plasma membrane, is the phospholipid layer that surrounds the cell and protects it from the outside environment.
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.
Ribosomal RNA<span> (rRNA) associates </span>with<span> a set of </span>proteins<span> to form ribosomes. These complex structures, which physically move along an mRNA </span>molecule<span>, catalyze the assembly of amino acids into </span>protein<span> chains. They also bind tRNAs and various accessory </span>molecules<span> necessary for </span>protein<span> synthesis.</span>
<span>Catabolism is all of the chemical reactions that break down molecules, either to extract energy or to produce simple molecules for constructing others. Anabolism refers to all of the metabolic reactions that build or assemble more complex molecules from simpler ones.</span>
