Question

1. Read the following excerpt from the Center for Disease Control about Antibiotic resistance and explain why this is an example of evolution by natural selection similar to the example shown in your textbook in Figure 1.16. What trait is being selected in this case?

"“Antibiotic resistance occurs when bacteria develop the ability to defeat the drugs designed to kill them. When bacteria become resistant, antibiotics cannot fight them, and the bacteria multiply. Antibiotic resistance is one of the most urgent threats to the public’s health. Antibiotic resistant bacteria can cause illnesses that were once easily treatable with antibiotics to become untreatable, leading to dangerous infections. Antibiotic-resistant bacteria are often more difficult to kill and more expensive to treat. In some cases, the antibiotic-resistant infections can lead to serious disability or even death. Overuse and misuse of antibiotics allows the development of antibiotic-resistant bacteria. Every time a person takes antibiotics, sensitive bacteria (bacteria that antibiotics can still attack) are killed, but resistant bacteria are left to grow and multiply. This is how repeated use of antibiotics can increase the number of drug-resistant bacteria. Antibiotics are not effective against viral infections like the common cold, flu, most sore throats, bronchitis, and many sinus and ear infections. Widespread use of antibiotics for these illnesses is an example of how overuse of antibiotics can promote the spread of antibiotic resistance. Smart use of antibiotics is key to controlling the spread of resistance.”

2. Fill in the table below:

Subatomic Particle	Charge	Location
	Negative
Proton
		Atomic nucleus

*The number of protons = ______________ number

*______________ + _________________ = mass number

*Valence electrons are electrons located in ______________________. Nitrogen has an atomic number of 7, hence it has ____________ valence electrons.

3. Fill in the summary table below regarding the unique properties of the water molecule

Property	Explanation of Property	Example of Benefit to Life
	Hydrogen bonds hold molecules together
Adhesion
High Specific Heat		Temperature changes in environment and organisms is moderate
Less dense as solid than as liquid
		Most chemical reactions in life involve solutes dissolved in water

Answer 1

1. The antibiotics resistance is an example of natural selection because - when we overuse antibiotics for any bacteria then maximum part of population get affected and die but some part of population not affected . Some changes occur in bacteria like mutation that will provide resistant to antibiotics. And that selected population reproduce further.

2 .
Subatomic Particle Charge Location
Electron Negative Orbitals
Proton Positive Atomic nucleus
Neutron Neutral Atomic nucleus

* The number of proton = Atomic number

* Protons+ neutrons = Mass number

* Valence electron are electron located in = Valence shell( outermost shell) . NITROGEN have 5 Valence electron.