The <u><em>correct answer</em></u> is:
He needs to select a more representative sample.
Explanation:
Choosing students from the basketball team for the sample he uses on a study of heart rates and exercise will be a biased sample. This is because students on the basketball team are potentially healthier than other students, which means that exercise will not have a large an effect on their heart rate as it would if they were not as healthy and not as physically fit.
In order to reduce the amount of bias, he should choose students from different groups throughout the school.
Answer:
A Ligase
B False
C To separate the double‑stranded DNA
Explanation:
The Polymerase Chain Reaction (PCR) is a technique widely used in molecular biology laboratories in order to make millions of copies of a specific sequence of DNA. PCR requires deoxynucleotide triphosphates (dNTPs) to synthesize new copies of the target DNA fragment, a thermostable DNA polymerase that adds nucleotides to new DNA strands, and primers that attach to complementary ends at each DNA strand. PCR has three phases: 1-Denaturation, where the double-stranded DNA molecule is heated to separate it into two single (separated) strands; 2-annealing, where the temperature is lowered in order to allow the primers to attach each DNA strand, and 3- extension, where the temperature is increased (again), and the thermostable DNA polymerase adds the appropriate dNTPs to new DNA strands. In consequence, annealing occurs at the lowest temperature. Moreover, during the denaturation stage, the temperature is increased at 90–95°C in order to denature the DNA strands into single strands.
I think that for 1 it’s either A or B as the kidneys and everything get air and the lungs release it.
For 2 is probably D as the others don’t really make much sense.
B.) A flowering plant with seeds that have one seed leaf is called a "M<span>onocotyledon"
Hope this helps!</span>
Answer:
it's water molecules
Explanation:
Polar bonds are intermediate between pure covalent bonds and ionic bonds. They form when the electronegativity difference between the anion and cation is between 0.4 and 1.7. Examples of molecules with polar bonds include water, hydrogen fluoride, sulfur dioxide, and ammonia
