Answer:
Option (d).
Explanation:
Mutation may be defined as the sudden, heritable change in the nucleotide sequence of the organism. Mutation may occur due to the errors in DNA replication or may occurs due to the mutagens.
Joshua and Lederberg experiment explains that mutation is the non adaptive and random process that occur in the organism. He used the replica plating of E.coli and grows them on streptomycin drug. The bacteria was grown on the the primary plate and they are transferred to the secondary plate with streptomycin drug in the growth environment. The resistant strain of bacteria grows in the streptomycin environment.The pattern of bacteria growth on the plate explained that mutation occurs randomly and it is a non adaptive process.
Thus, the correct answer is option (d).
Explanation:
Natural selection is the mechanism that is responsible for the evolution of organisms.
In the given case, the Freshwater shrimp has been introduced to a pond in which the two species with variations are introduced.
The <em>C. cantonensis </em>is brighter in color whereas the <em>C. multidentata</em> is mottled drab in color. The predator fish can feed easily on the species which is brighter therefore <em>C. cantonensis</em> is more susceptible. The mottled drab species is not easily predated by the species.
The 30 % offsprings of <em>C. cantonensis</em> can survive till the reproductive age whereas 75% of C. multidentata. This shows that natural selection has acted on the color of the shrimp species selected against the predator fish species.
The species with mottled drab color is the result of the differential reproductive rate.
Answer: the cfu/g Gram-negative bacteria in the fecal sample is C = 3.0 × 10^3
Explanation:
We know that; Gram negative bacteria looks pale reddish in color under a light microscope from Gram staining.
therefore
There are 30 red bacterial colonies counted.
1 mL of from tube 1 was removed and added to tube with 99 mL saline (tube 2) dilution is 1/100.
transferred volume into the plate is 1 mL.
Now, we have to determine the cfu/g Gram-negative bacteria in the fecal sample
Formula to calculate CFU/g bacteria in fecal sample is expressed as;
C = n/(s×d )
where C is concentration (CFU/g)
, n is number of colonies
, s is volume transferred to plate
, d is dilution factor.
so we substitute
C = 30 / ((1/100) × 1)
C = 30 / 0.01
C = 3000
C = 3.0 × 10^3
THERFERE, the cfu/g Gram-negative bacteria in the fecal sample is C = 3.0 × 10^3
Answer:
As we increase the force on an object the acceleration increases proportionally. ... Therefore, if you double the force you double the acceleration. If you increase the mass at a given force the rate of acceleration slows. Therefore, mass is inversely proportional to acceleration.
Explanation:
