Answer:
The answers are:
1. initial composition of microbial community (controlled variable)
2. age of the mice (controlled variable)
3. change in body fat (dependent variable)
4. diet (independent variable)
5. weight gain (dependent variable)
6. final composition of the microbial community (controlled variable)
Explanation:
Before I go ahead to explain each of the choices of classification, let us define each of the different types of variable.
1. Independent variable: this is a variable that is under the control of the experimenter. It is made up of the factors that are being tested. In our example, the independent variables is; diet. The aim of the experiment is to study the effect of the type of diet on the mice. The diet can also be varied and assigned at will by the experiment.
2. Dependent variable: a dependent variable is one whose outcome is reliant on the effect of the changes in the independent variable. It is the factor to be measured. In our example, the factors that obey these definitions are; change in body fat and weight gain. these two factors depend on the types of diet taken by the mice, hence they are the factors to be measured.
3. Controlled variable: these are variables that are kept constant throughout the experiment to rule out biases, because they produce the same effect on the dependent variable as the independent variable and must be keep constant or uniform in the test groups. in our example, the factors that are controlled include; initial and final compositions of the microbial communities and the age of the mice, because the microbial composition if not uniform among the groups can cause biases in how the diets are processed, and the age of the mice also must be uniform to avoid age-related differences in the processing of the diets
Answer:
The DNA strands are not free in the nucleus, but forming a compact structure called chromatin along special proteins, known as histones. The chromatin structure has an important role in gene expression, as the level of compaction and the histone modification act as signals for the transcription machinery
In order to be transcribed, different areas in the genome need to unfold from the histone proteins, so the RNA polymerase can access the DNA.
That means, <u>that DNA sequences that transcribe at high rate, are more often unfold from the histones, and more exposed to other proteins to bind them. Particularly, those areas are more sensitive to the attack of endonucleases, such as DNAse I.</u>
As a consequence, an assay of DNAse I digestion can be used to identify highly sensitive or resistant to DNAse cleavage areas in the genome, and therefore serve as an insight to which sequences are more and less transcriptionally active.
Answer: B. reforestation
Reforestation is the process of growing plants and trees in an area on large scale in order to create land a forest reserve which can allow the growth and abundance of floral and faunal species in future. Reforestation is the biodiversity restoration method that the biologist should use to meet their goals like : recreation of habitats for wildlife in a particular area, help against climate change as plants are the fixers of atmospheric carbon utilize this for photosynthesis and prevents the raising of atmospheric temperature.
It states that, for a given mass of an ideal gas at constant pressure, the volume is directly proportional to its absolute temperature, assuming in a closed system.
p1/t1=p2/t2
