Answer: four criteria to establish a causative relationship between a microbe and a diseases
Explanation:
1- "Bacteria must be present in every case of diseases"
2- "Bacteria must be isolated from the host with the diseases and grown in pure culture"
3- "The specific diseases must be reproduced when a pure culture of bacteria is inoculated into a healthy susceptible host"
4-"Bacteria must be recovered from the experimentally infected host"
The correct answer is:
a. Jupiter
Explanation:
In 1610, Galileo Galilei turned his rudimentary telescope on Jupiter and understood that it had 4 large moons orbiting it: Io, Europa, Ganymede, and Callisto. This was an amazing discovery because it explained that Earth was not the center of the Universe as champions of the geocentric view assumed.
Answer:
The correct answers are: Dilution factor = 250 and concentration of DNA in undiluted sample = 2.5 μg/μl.
Explanation:
- Volume of DNA taken = 2 μl.
- Volume of added water = 498 μl.
- Total volume of the sample = 2 μl + 498 μl = 500 μl.
- Dilution factor =
- A₂₆₀ of the given sample is = 0.2.
- We know that 50 μg/ml concentration of pure double stranded DNA gives an absorbance, A₂₆₀ = 1.
- Again, Concentration of DNA(µg/ml) =
µg/ml. - =
μg/ml. - In order to convert it into μg/μl, we have to divide the above value by 1000, hence we get,
μg/μl.
Both bases need to twist hard to facilitate the hydrogen bond which is energetically expensive event; thus hydrogen bonds forming functional groups are not complementary in adenine and cytosine
