Question

Darwin hypothesized that there are definite steps to natural selection. Consider the model of bacterial resistance to antibiotics. Use the Roman numerals (I - III) to guide you through the steps to describe how Darwin would explain antibiotic resistance.

A) There is a change in the environment: an antibiotic is added. Some of the bacteria adapt to the new environment. They survive and reproduce.

B) In any population, variation exists. Some bacteria are resistant to antibiotics. Most bacteria die, but the bacteria that are resistant survive and reproduce.

C) Sexual reproduction of bacteria cause variation. Some bacteria survive antibiotics and some do not. Regardless, over time all of the bacteria should become extinct.

D) In a population of bacteria that are exposed to antibiotics, some bacteria are able to change their genetic make-up and survive. The new genotype is passed on to offspring.

Answer 1

B. In any population, variation exists. Some bacteria are resistant to antibiotics. Most bacteria die, but the bacteria that are resistant survive and reproduce.

Step-by-step explanation:

Answer 2

A) There is a change in the environment: an antibiotic is added. Some of the bacteria adapt to the new environment. They survive and reproduce.

Step-by-step explanation:

I. Variation: Different organisms manifest different appearances and behaviors. It depends whether it's a body size, hair color, certain marks on one's face, tone of the voice, number of offspring. Some attributes are the same in every individual: for example, everybody has two eyes, one mouth, one nose, etc.

II. Inheritance: Certain attributes are passed from a parent to an offspring. They are passed heritably, while some other attributes are very environmentally oriented and have nothing to do with inheritance, but the adapting to the environment.

In this phase, certain species produce more offspring and they are fighting for their survival. Due to that, major environmental changes occur as they produce more and more each time, which leads to struggling for resources, and it's further passed to the next generations.

III. Selection -- it's manifesting by the scheme where organisms who are better at adapting to the environmental changes have a bigger chance to mature. When they do, they reproduce and pass all the qualities to their offspring. Therefor, bacteria that is better at adapting to the new environmental changes, is more likely to survive and reproduce and it goes on like that in circles.

IV Population is growing bigger and bigger and as a result we have an evolution.