Answer: One of the ways that people of ancient times classified plants and animals is by use. Today, group the creatures, as they do the plants, on the premise of shared physical attributes. They put them in a progressive system of groupings, starting with the kingdom Animalia and continuing through phyla, classes, orders, families, genera and species.
Explanation:
<span>The correct answer is b. Option a is incorrect because these models can demonstrate scientific theories, but they don't prove scientific theories (you would need experiments for that). Option c is incorrect because the models aren't always representing something abstract (i.e. DNA is very real, just very small). Option d is incorrect because they don't precisely mimic something in nature, but instead help us visualize something in nature that is difficult to see or comprehend.</span>
Answer:
The answer is A.
Explanation:
The example experiment given in the question would be a valid experiment because there is more than one variable.
For an experiment to be valid, there have to be a dependent variable, an independent variable, a constant and a control aspect.
In the example, we can say that the independent variable which has the direct effect on the aspect that we are looking for, the freezing point, is the amount of salt in the water. Therefore the dependent variable is the freezing point which is the part being observed for any change. The constant can be the amount of water used because it is static and the control can be the temperature the mixtures are exposed to which does not change throughout the experiment.
Therefore the answer is option A.
I hope this anwer helps.
B. At high temperatures, the active site of the enzyme is damaged and it is no longer able to attack itself to the required substrate as its shape will no longer match.
Answer:
it results in 2 exact copies of the original dna strand
Explanation:
The dna is unzipped and the two strands are used as templates for the 2 new dna molecules
