Answer: C
Explanation: Took the test
Answer:
Taq polymerase is a thermostable which states that it can even work at higher temperature. The main function of using this enzyme is that it is used to amplify the DNA which will help in producing ample amount of DNA sample.
The enzyme activity is temperature dependent. The denaturation and annealing steps of the PCR occurs at very high temperature.
Any other enzyme used at such an high temperature would have decreased the enzyme activity and the procedure would not be completed.
The actual number of atoms of each element present in the molecule of the compound is represented by the formula known as molecular formula.
Molar mass of the unknown compound = 223.94 g/mol (given)
Mass of each element present in the unknown compound is determined as:
- Mass of carbon,
:

- Mass of hydrogen,
:

- Mass of chlorine,
:

Now, the number of each element in the unknown compound is determined by the formula:

- Number of moles of
:

- Number of moles of
:

- Number of moles of


Dividing each mole with the smallest number of mole, to determine the empirical formula:


Multiplying with 2 to convert the numbers in formula into a whole number:
So, the empirical formula is
.
Empirical mass = 
In order to determine the molecular formula:
n = 
n = 
So, the molecular formula is:

Answer:
Spindle fibers form.
DNA condenses into chromosomes.
Explanation:
Prophase is the first stage of mitosis. Mitosis produces 2 daughter cells from a parental cell.
Spindle fibers form - this is true. During prophase, the mitotic spindle forms. Later during mitosis the spindle attaches to the centromere of chromosomes and pulls them to opposite ends of the cell prior to division
DNA condenses into chromosomes. - this is true. In the nucleus during interphase, the DNA is relatively loosely compacted. However, prior to division, the DNA is condensed into structures called chromosomes which are then paired up and distributed to the daughter cell.
Chromosomes move to opposite ends of the cell. - this is false. This happens during anaphase
Nuclear membrane begins to re-form. - this is false. This happens during telophase.
Answer:
False
Explanation:
It is not true that this is an example of a chemical reaction. This is a typical example of physical reaction.
Most physical changes are often phase changes.
- A phase change is a change in the physical state of a body.
- In this change, it is from solid to liquid.
- Now new substances are formed.
- When substances are changed from one form to another, it is a physical change.
In a chemical change, a new substance is formed at the end of the process.