What is the likely long-term consequence of an increase in the relative percent of greenhouse gases in Earth’s atmosphere?a. Earth’s average temperature will increase.
b. Earth’s average temperature will decrease.
c. Earth will experience greater temperature extremes.
d. Earth’s average temperature will be unaffected.

Ans. (b). has a genome made of RNA.

Retroviruses are viruses with RNA molecules as their genome. They insert a copy of their RNA genome into the host cell DNA and change the cell genome. These viruses are generally known as single-stranded positive-sense (+ strand) RNA viruses.

Examples: Human immunodeficiency virus and hepatitis B virus.

Thus, the correct answer is option (b).

Ans. (a). through reproduction of the host cell.

Lysogenic life cycle is a virus reproductive cycle that involves integration of viral nucleic acid into host's genome or formation of a replicon in host's cytoplasm.

The host cells (bacterial cells) remain alive and reproduce normally, so thus, viruses reproduce through the reproduction of host (bacterial cells).

Thus, the correct answer is option (a).

Making observations is the step of scientific method in which information is obtained through the senses.  

Making an observation is the first step of scientific method where scientists gets curious about a natural occurrence or a phenomenon.

Further Explanation.

• Scientific method involves a process where researchers or scientists search for answers to certain questions and solutions to problems.
• Scientific methods are used by scientists or researchers to test a given hypothesis.

Steps involved in Scientific method

Making an observation and asking question.

• Making observation is the first step of any scientific process. The scientists make observations about a natural phenomenon.

• After making observations scientist asks a question about an observed phenomenon or pattern.  

• Observations may be qualitative where the occurrences are described in ways that do not use numbers or quantitative where observations contain numbers and other features.

Formulating a hypothesis

• Hypothesis refers to probable answers to the question asked and one that can be tested experimentally. Hypothesis is therefore a possible explanation for a given observation or occurrence.

• For the observation that we experience alternating periods of light and darkness that correspond to the movement of the sun, moon, and clouds. The hypothesis here would be; The earth rotates on its axis for 24 hours, thus, exposing one side to the sun or else the sun revolves around the earth for twenty four hours.

Designing and performing experiments

• Suitable experiments be carried out  to test the  validity of the hypothesis formulated.

• Experiments refers to organised measurements or observations normally made under controlled environment.

Accept or modify the Hypothesis  

• The experiment conducted helps the researchers or scientists to determine whether the hypothesis formulated is valid. If the hypothesis is valid then they proceed to the next step of scientific method.

• However, if the experiments demonstrate that the hypothesis is incorrect then it must be corrected for further experimentation.

Developing a law and/or a theory  

• After conducting experiments and analyzing the results obtained, the researchers may test whether the results are reproducible and hence a law may formulated to allow general prediction.

• A scientific law describes a phenomenon or pattern, it describes what happens but does not explain why.

Key words: Scientific method, making observation

Learn more about;  

1. Scientific method; brainly.com/question/1506591
2. Steps involved in scientific method: brainly.com/question/1506591

Level: high school  

Subject: Biology

Topic: scientific method  

Sub-topic: steps involved in scientific method