Conducting a serial dilution along with a plating experiment allows for the quantification of bacteria or microbes present in a specified volume of a soil sample. In this standard procedure, a designated volume taken from the lesser dilution is placed on a median plate, which is then allowed to incubate for the appropriate duration. The resulting colonies are counted to ascertain the overall Colony Forming Units (CFU) based on the volume of the sample that was plated and the amount of soil sample that was utilized. The calculation follows this formula: CFU/ml = Number of colonies counted × dilution factor / volume plated. In this scenario, we have: Number of colonies counted = 97, dilution factor = 10^(-6), and volume plated = 1/10 = 0.1. Therefore, the calculation proceeds as: CFU/ml = 97 * 10^(-6) / 0.1 = 97 * 10^(-7) CFU/ml. This figure represents the concentration of bacterial colonies per unit volume of the plated sample. Given that the original soil sample weighs 1g or 1000 mg, the total number of bacteria can be estimated with this formula: Amount of bacteria in original sample = 97 * 10^(-7) CFU/ml × 1/1000 mg = 9.7 * 10^(-3) CFU/mg.
The answer is option (d). Enzymes act as biocatalysts that can accelerate biochemical reactions within the body. Their functioning is optimal at specific pH and temperature conditions. Excessive heat or cold treatment can impair enzyme activity, with cold decreasing activity due to reduced molecular movement.
Hydroponic farming refers to cultivating plants without soil. Terrestrial plants can grow with their roots solely in a mineral solution, or the roots may be supported by an inert medium such as perlite or gravel. The farmer’s plants might have been failing at the same rate since some plants require soil, or perhaps the roots were simply too long.
If I'm correct, please mark it as the best answer; if not, let me know where I went wrong
and feel free to ask me any additional questions. Have a nice day!
Selecting the appropriate type of material for placement can help mitigate or ideally eliminate post-surgical tooth sensitivity. This choice can prevent the need for further endodontic procedures if the sensitivity continues. The application of resin-based amalgams remains a safe practice, involving a thin layer of resin that is allowed to set briefly before curing. <span>Clinical studies have shown that there is often a lack of proper use of curing lights. Ineffective curing light application can lead to an increase in complaints of postoperative tooth sensitivity.</span>
Response:
B. The meanings of the prefixes chemo- and photo- point to the source of electrons.
Explanation:
The term chemo refers to chemical/drug, whereas photo relates to light. This can be demonstrated through the following examples:
Chemotherapy = treatment using chemicals
Phototherapy = treatment utilizing light
