No, the solution with bacteria in it needs to be diluted in order to be in the range of 30 – 300.
A colony-forming unit –CFU is used to estimate the number of viable (ability to divide by binary fission) microbes in a sample.
A sample of microbes is diluted and spread on a plate. Then, the number of colonies is counted, assuming that each colony have grown from a single colony-forming unit, or CFU.
Plates with more than 300 colonies are difficult to count while those with less than 30 colonies give statistically unreliable numbers of colonies to count.
Answer: student 4
Explanation: she is doing the same exact experiment all over again and not changing the things, which can make it even more of an accurate answer
Answer:
When sulfurous, sulfuric, and nitric acids in polluted air and rain react with the calcite in marble and limestone, the calcite dissolves. In exposed areas of buildings and statues, we see roughened surfaces, removal of material, and loss of carved details. Stone surface material may be lost all over or only in spots that are more reactive.
Explanation:
You might expect that sheltered areas of stone buildings and monuments would not be affected by acid precipitation. However, sheltered areas on limestone and marble buildings and monuments show blackened crusts that have peeled off in some places, revealing crumbling stone beneath. This black crust is primarily composed of gypsum, a mineral that forms from the reaction between calcite, water, and sulfuric acid. Gypsum is soluble in water; although it can form anywhere on carbonate stone surfaces that are exposed to sulfur dioxide gas (SO2), it is usually washed away. It remains only on protected surfaces that are not directly washed by the rain.
Answer: There are two ways to determine the age of a dinosaur fossil. One is called relative geologic time, which involves deciding whether one dinosaur fossil is older or younger than another. Geologists then measure the proportion of parent and daughter atoms present in the ash crystals to determine the crystal's age.
Explanation:
Answer:
RrYy (F1 generation)
Explanation:
This is a typical dihybrid cross involving two genes in the pea plant; one coding for seed colour and the other for seed shape.
According to Mendel's law of dominance, an allele is capable of masking another allele in a gene, the allele that masks or is expressed is called the DOMINANT allele while the allele being masked is called RECESSIVE allele.
Homozygosity of a gene refers to it having the same type of alleles while heterozygosity refers to having different alleles.
In this example, allele for Round (R) and Yellow (Y) pea is dominant over the allele for Wrinkled (r) and green pea respectively.
Homozygous round green pea (RRyy) crossed with Homozygous wrinkled yellow (rrYY) will give rise to a heterozygous round yellow (RrYy) F1 offsprings.