<span>The three essential principles of test construction are listed below:
I. Standardization
II. Reliability
III. Validity
</span>Standardization- To standardize a test means that test is given to a large, representative sample of people, in order to establish the norms that future test takers are compared against (using a normal distribution)
Reliability - This principle requires that a test must produce reliable, consistent results when it is repeated. The reliability of a test can be verified using the test-retest method or the split-half method.
Validity - This refers to the ability of a test to measure what it was designed to measure.
Answer:
The correct answer is physical boundary.
Explanation:
In my opinion, the kind of boundary it signifies is the physical boundary. The physical boundary is the most general type and is a naturally taking place obstruction in between the two regions due to the existence of either an ocean, river, desert, or mountain ranges. At various occasions, the political boundaries between the states or the countries form along the physical boundaries.
A) proteins are made of amino acids ( if you want to describe it more you can talk about the central dogma, dna to mRNA then mRNA to amino acids and amino acids to proteins. and you can talk about the structures of dna, primary secondary tertiary quaternary). nucleic acids are made of nucleotides ( cytosine (C), thymine (T), adenine (A), guanine (G))
Answer:
a) The response indicates that a pH below or above this range will most likely cause enolase to denature/change its shape and be less efficient or unable to catalyze the reaction.
b)The response indicates that the appropriate negative control is to measure the reaction rate (at the varying substrate concentrations) without any enzyme present.
c)The response indicated that the enolase has a more stable/functional/correct/normal protein structure at the higher temperature of 55°C than at 37°C because the enzyme is from an organism that is adapted to growth at 55°C.
Explanation:
Enolase catalyzes the conversion of 2-phosphoglycerate to phosphoenolpyruvate during both glycolysis and gluconeogenesis.In bacteria, enolases are highly conserved enzymes and commonly exist as homodimers.
The temperature optimum for enolase catalysis was 80°C, close to the measured thermal stability of the protein which was determined to be 75°C, while the pH optimum for enzyme activity was 6.5. The specific activities of purified enolase determined at 25 and 80°C were 147 and 300 U mg−1 of protein, respectively. Km values for the 2-phosphoglycerate/phosphoenolpyruvate reaction determined at 25 and 80°C were 0.16 and 0.03 mM, respectively. The Km values for Mg2+ binding at these temperatures were 2.5 and 1.9 mM, respectively.
Enolase-1 from Chloroflexus aurantiacus (EnoCa), a thermophilic green non-sulfur bacterium that grows photosynthetically under anaerobic conditions. The biochemical and structural properties of enolase from C. aurantiacus are consistent with this being thermally adapted.
The scientific method is a problem-solving approach used in Biology and other scientific disciplines. This method has five basic steps which help scientists test their hypotheses. The first step of the scientific method is to make an observation. In this particular example, the scientist observes probably that salt has chemical and physical properties which could affect the life cycle of bacteria. The second step would be to ask a question and that would be to ask whether salt indeed has any effect on that particular type of bacteria that he/she studies. The third step would be to form a hypothesis and that would be to state that the specific bacterial type will be strongly affected by the salt. The fourth step would be to predict that if the scientist exposed this bacterial type to a salty environment, the bacteria would not survive. The fifth and final step is to test this prediction and if the bacteria do not survive, then the scientist can conclude that salt affects this bacterial type.
