Answer: CFU/mL = 14200 CFU/mL
Explanation:
Microorganisms are very small and difficult to count directly. Instead, a laboratory technique is used to count CFUs (Colony Formation Units). This involves making dilutions of a microbial suspension and spreading it on thin layers of agar containing nutrients for growth in Petri dishes also called agar plates. After incubation under ideal conditions, some plates are completely covered with microbial growth; some have little or no growth; and some are covered with individual isolated "spots", which are microbial colonies. Since a colony may consist of a single organism or a group of microbes, the dots represent a CFU.
To calculate the viable count of the stock culture, you have to count the number of colonies, multiply by the dilution and the result will be the plate count in CFU.
So, the equation is:
CFU/mL = Number of colonies / (Volume trasferred to plate x dilution blank)
100 microliters = 0.1 mililiter
1/10 = 0.1 (dilution factor)
Replacing the information from the question:
CFU/mL = 142 / (0.1 mL x 0.1)
CFU/mL = 14200 CFU/mL
Answer:
D. Organic Matter is the correct answer
Answer:
The chance of a normal couple having a child with down syndrome is 1 to 600 births.
Explanation:
Down syndrome is a genetic flaw that occurs when the fetus is being formed.
A human cell considered normal has 46 chromosomes, divided into 23 pairs. For some unknown reason, an error may occur at the beginning of embryonic development and an extra chromosome is created, which binds to par 21. The result is cells with 47 chromosomes. This causes the said syndrome.
It is important to know that this failure happens at random. It is nobody's responsibility. It has not been proven to date that lifestyle, actions during pregnancy, smoking, drinking, medicines, environmental factors or kinship between the couple can influence this occurrence. She is not contagious either. The likelihood of a normal couple having a child with the syndrome is approximately 1 to 600 births.
Answer:
a Anaphase I
b Metaphase I
c Telophase I
d Anaphase II
e Prophase I
f Telophase II
Explanation:
Prophase I begins after the DNA has been duplicated, as shown in picture e. The chromosomes are condensed, and also visible, which is apparent in picture e.
The next stage is called Metaphase I, in which the pairs of homologous chromosomes align at The the centre of the cell and the spindle fibres attach, as shown in picture b.
The pairs of chromosomes are pulled apart to opposite poles of the cell by the spindle fibres., as shown in picture a. This stage is called Anaphase I.
Then, a process called Telophase I occurs, when the cell divides into two daughter cells. One of these cells is shown in picture c.
Picture d shows the stage Anaphase II, where the spindle has attached and the chromatids are pulled to the opposite poles of the cell.
The final picture left is picture f, which shows the daughter cell at the end of meiosis II, where the nuclear envelope is reforming, as in telophase II.
