Following general conditions are necessary for natural selection to occur in population:
- More organisms are born than can survive.
- Organisms vary in their characteristics, even within a species.
- Differences in reproduction and survival are due to variation among organisms.
According to Charles Darwin's theory of evolution by natural selection, organisms that possess heritable traits that enable them to better adapt to their environment compared with other members of their species will be more likely to survive, reproduce, and pass more of their genes on to the next generation.
Galapagos Finches: The Galapagos finches studied by Darwin on his famous voyage are probably the most common example of natural selection.
A positively charged ion is called cation.
A negatively charged ion is called anion.
A salt is formed by the ionic bonding of a cation and an anion.
pH is a measure of the hydrogen ion concentration in a solution.
Answer:
- The Island population likely has fewer alleles-that is versions of genes-than the mainland population.
A- Agree <u>B- Disagree</u>
- Genetic drift is more pronounced in the island population than in the mainland population in these first few generations
A- Agree <u>B- Disagree</u>
- Some harmful traits may have become more common in the island population than in the mainland population
<u>A- Agree</u>- B- Disagree
- Biologist observed genetic drift but not evolution
<u>A- Agree</u> B- Disagree
Explanation:
If there was genetic drift, then allele frequency either increased or decreased by chance, irrespective of natural selection that is irrespective to weather those alleles helped individuals survive in the island environment. In molecular genetic data, there are statistical signature in the population variation that indicate weather selection or other processes occurred.
Placenta Previa
Placenta Previa is a disorder
that arises from the implantation and development of the placenta in the lower segment
of the uterine. The cause of this disorder is unknown. The three types of placenta
previa are complete, partial and marginal previa. The most common symptom of placenta
previa is painless bleeding during the third trimester.
Answer:
See the answer below.
Explanation:
Antibiotic-producing bacteria are generally known to have a mechanism that enables them to be resistant to their own antibiotics. The mechanism that enables them to be resistant to their own antibiotic depends largely on the mode of action of the antibiotic substance.
Some of the popular mechanisms used by bacteria to counter their own antibiotic substance include a mutation in the target gene, production of enzymes that inactivate the antibiotic compounds, or efflux of the compounds.
<u>In the case of </u><u><em>Streptomyces griseus</em></u><u>, the inactivity of streptomycin has been linked with the production of a phosphatase inhibitor that prevents streptomycin from getting access to the target site. Hence, the organism is not harmed by its own antibiotic.</u>