Answer and Explanation:
The correct answer is option B
B. The treated glioblastoma cells were cultured in the presence of an inhibitor from umbilical cord stem cells, but the control cells were cultured without the inhibitor.
Speed = 17.2 m/s...................
Answer:
Human cells can readily absorb folic acid; bacteria cells cannot.
Explanation:
Bacterial cells cannot absorb folic acid and synthesize it. On the other hand, humans do not synthesize folic acid in their cells. They rather obtain it from the diet. Sulfa drugs, for example, sulfanilamide resemble p-aminobenzoate (PABA). PABA is a molecule that is used as a substrate in the synthesis of the coenzyme folic acid. The sulfa drugs serve as competitive inhibitors and compete with PABA for the catalytic site of an enzyme involved in the folic acid synthesis. This prevents the synthesis of folic acid in bacterial cells and thereby, inhibits bacterial growth.
Answer:
Option (1), (2) and (3).
Explanation:
DNA is the genetic material of all the living organisms present on earth. The DNA contains the nitrogenous bases, pentose sugar and the phosphate group. DNA strands runs in the opposite direction and shows polarity.
Watson and Crick explain the structure of DNA based on the X ray diffraction produced by Rosalind. According to the structure, chromosomes are present in the nucleus and contains the DNA and wrapped around the proteins. The genes is considered as the functional segment of DNA.
Thus, the correct answer is option (1), (2) and (3).
Answer no 8:
The correct option is D) Antelopes with muscular legs are bale to outrun their predators better than antelopes with poor muscle tone. Thus they lived to reproduce.
Explanation:
Genetic variations in a population are the main reason that natural selection tends to occur. Natural selection favours those organisms which have better characteristics.The organisms with better traits are able to reproduce and pass on their characteristics to their offsprings.
Answer No 10:
The correct option is A) Phenotype directly influences the interaction of an organism with its environment.
Explanation:
The interactions between the phenotypic traits and the environment analyze whether a particular organism will be able to survive and pass on its characteristics to its offspring. Hence, the phenotype directly influences the interaction of an organism with its environment.
Answer No 9
The correct option is A) resistance to a virus
Explanation:
Mutations can be described as any changes which occur in the DNA of an organism. Mutations might be beneficial or harmful depending on the location where the mutation arises. Viruses are usually harmful for eukaryotes. Hence, the correct option is A.
Answer No 11:
The correct option is C) Giraffes with longer necks survived because they were better suited to the environment.
Explanation:
Natural selection tends to favour those organsims which are better suited to live in an environment. Those organisms with better characteristics are able to survive and pass on their traits to their offsprings.
The giraffes with longer necks were better adapted to live in the environment and hence were favoured by natural selection.
Answer No 12:
The correct option is D) selective breeding
Explanation:
Selective breeding can be described as a technique in which organisms with better characteristics are crossed, so that offsprings with better characteristics can be produced. Selective breeding is done by humans where as natural selection is done by the nature.
