The geometric method gives scientists the spreading direction to go with the spreading speed
Answer:
Petri plates are incubated upside down to prevent contamination.
Explanation:
The plates are always incubated inverted or turned upside down on their covers during storage. This is done to prevent evaporation if plaque is stored for long periods, which can affect the growth efficiency of bacteria, or allow contamination by multiplying unwanted organisms such as mold.
Once the plaques have been filled with a damp suspension of bacteria, it should be allowed to evaporate shortly before overnight incubation. However, a moderate amount of moisture will still be present. If plaque is not inverted during incubation, bacteria will not be able to attach to the culture medium properly, which will either prevent them from growing and forming colonies properly or will encourage the growth of undesirable microorganisms.
Any of these results will invalidate the experiment. In addition, any condensation or moisture can cause streaking, which will make it difficult to select and analyze separate colonies. After bacteria form colonies, plaque is also stored upside down to maintain moisture levels.
Answer:
The sequence of nucleotides, coded in triplets (codons) along the mRNA, that determines the sequence of amino acids in protein synthesis. The DNA sequence of a gene can be used to predict the mRNA sequence, and the genetic code can in turn be used to predict the amino acid sequence.
The answer is; D
The angle at which the sun rays strike the earth at the equator is more or less 90 degrees while you move towards the poles, it much less than this. This means that the unit of sunlight per surface area received at the equator is higher than that at the poles. This is why the equator is always warmer than the poles.
