Answer:
B Physical separation of populations prevents interbreeding and mixing of gene pools.
Explanation:
Geographic isolation means two populations are unable to reproduce with one another. This means that over time, the variation in the gene pool will be different for one group compared to the other, and the species will genetically diverge from one another. resulting in speciation.
Cytokinesis, it's the division of a cell at the end of mitosis and the cell divides into two daughter cells.
Answer:
Broad-spectrum antibiotics can cause antibiotic resistance.
Explanation:
- Antibiotics are the substances that inhibit the growth of or kill the bacteria and hence, these are used as medications for the treatment of a lot of bacterial diseases.
- These antibiotics can either be of broad-spectrum or the narrow spectrum.
- The broad-spectrum antibiotics are the ones that are effective against a variety of bacteria, both gram-positive and negative whereas the narrow-spectrum antibiotics are the ones that target only a specific type of bacteria.
- Since the bacteria can mutate very fast and hence, develop antibiotic resistance, the doctors usually avoid prescribing broad-spectrum antibiotics and only use them when the causal bacteria is completely unknown.
- Hence, in the given case the provider prescribes separate medications for both types of bacteria.
Answer:
The correct option is C. Rare alleles tend to remain rare even when they are dominant.The distribution of a gene among individuals is determined by mating and environmental factors.
Explanation:
Most people believe that a rare allele would only be recessive. But this is not correct. A rare allele can be dominant. The frequency of an allele to occur in a population will depend on the environmental factors. The alleles which code for traits that are best suitable for living in an environment will be seen in more abundance. The frequency of an allele to occur in a population also depends on the breeding trends of the population.
Answer: d. Extracellular matrix was discovered more than 20 years ago.
Explanation:
According to biological sciences, the extracellular matrix is a matrix that consists of three dimensional network of extracellular macromolecules such as enzymes, collagen and glycoproteins which provide structural and biological support for surrounding cells as well.
It is found that it is discovered over 20 years ago in the matrix formed in the mouse EHS sarcoma. Therefore, correct answer is (d).