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What elements are in the compound NaCl (table salt)?

Biology homework help

Name:       Sec:
Chapter 2: The Chemistry of Life
Module 2.1 All life is made of molecules, which are made of atoms.
1. The scientific study of matter is chemistry.
2. Fill in the table regarding the states of matter by providing an example of each that is NOT in your book.

Solid Liquid Gas
Example


3. Match the following terms with their correct definitions:
matteratommoleculeelementcompound
a. The smallest unit of matter that retains the properties of its specific type of matter:
b. A substance that cannot be broken into a simpler substance:
c. Anything that occupies space and takes up mass:
d. Substances with two or more elements in a fixed ratio:
e. Atoms that are bonded to one another:
4. Fill in the following diagram that illustrates the relationship between compounds and elements:
a. 
b. 

5. Neapolitan ice cream is vanilla, chocolate, and strawberry combined in a 1:1:1 ratio. Briefly explain how Neapolitan ice cream is a good analogy for compounds.

6. Complete the following diagram with regard to chemical reactions:


Module 2.2 All matter consists of chemical elements.
7.       are substances that cannot be broken down into simpler substances.
8. What elements are in the compound NaCl (table salt)?

9. Is H2O (water) an element? If not, explain your answer.

10. Where can you find all of the elements listed by atomic number?

11.  Complete the following diagram of an element from the periodic table:



12. Which of the following elements make up the majority of organisms?
a. |_| Carbon
b. |_| Hydrogen
c. |_| Oxygen
d. |_| Nitrogen
e. |_| All of the above
13. Fill in the following table regarding elements found in organisms:

Required in large amounts Required in small amounts Required in tiny amounts
% contribution to your cells


Example


Module 2.3 Atoms are composed of subatomic particles.
14. Atoms are made of smaller substances referred to as      .
15. An atom comprises what three smaller substances:
1. 
2. 
3. 
16. Complete the following table regarding atoms:

Subatomic particle Mass Charge









17. Match the following terms to the proper characteristic. Some terms may be used more than once:
Nucleus, proton, electron, neutron, electron shell, subatomic particles
a. Has no mass:
b. Found in the nucleus:
c. Center of the atom:
d. Contains electrons:
e. In constant motion:
f. Protons, electrons, neutrons:
18. Complete the following diagram of the atom:

           
     
     
19. An atom of carbon has six protons. What if you change the number of protons to seven? Is it still carbon? Explain your answer.

20.       vary in the number of electrons.
21. Briefly explain how you can have two atoms of carbon, yet each have a different atomic weight.

22. Atoms are considered to be electrically neutral (no overall electric charge) unless stated otherwise. If you have an ion (an atom with an electric charge), what subatomic particle has to vary? Breifly explain why.

23. Complete the following table by filling each line with the correct volume:

Element Atomic Number Mass Number Number of Protons Number of Neutrons Number of Electrons
Carbon-12
12 6

Nitrogen-14


7 7
Chlorine-35
35 17

Oxygen-16



8
Carbon -14




Module 2.4 Atoms are held together by chemical bonds.
24. What are the three ways in which atoms can interact with one another with respect to their electrons?
1. 
2. 
3. 
25. An attractive force that holds two atoms together is generically referred to as a(n):
a. |_| molecule
b. |_| chemical bond
c. |_| electron cloud
d. |_| compound
26. Complete the following diagram illustrating ionic bonds. Atom X gives one |_|electron to each atom Y. What are the ions that form as a result? Put the charges under each atom.


27. Which of the following would be considered a covalent bond?
a. |_| double bond
b. |_| single bond
c. |_| triple bond
d. |_| all of the above
28. Methane is to a nonpolar covalent bond as H2O is to a(n):
a. |_| chemical bond
b. |_| ionic bond
c. |_| polar covalent bond
d. |_| triple bond
29. Complete the following diagram illustrating chemical bonds:
a. 
b. 
c. 
d. 

D
C
B
A
30. Match the following terms to their definition:
Ionic bond, covalent bond, polar covalent bond, nonpolar covalent bond, hydrogen bond
a. A weak attraction between a slightly positive hydrogen and a slightly negative atom:
b. Two atoms sharing electrons:
c. Atoms sharing electrons equally:
d. A bond that forms between oppositely charged atoms:
e. A bond based on the unequal sharing of electrons:
31. Label the different bonds on the following diagram:


Module 2.5 The structure of water gives it unique properties.
32. True or False. If false, make a true statement: Electrons are shared equally between the oxygen and hydrogen atoms in a molecule of water.
33. Label the following diagram with the following terms:
Hydrogen bond, unequal sharing of electrons, – charge, + charge
A

E
D
C
B
a. 
b. 
c. 
d. 
e. 
34. Briefly explain what would happen to a large body of water (think Lake Superior) if ice didn’t float.

35. Because water is      , it is able to dissolve many of life’s important substances.
36. Oils are nonpolar substances (molecules formed by nonpolar covalent bonds) that do not interact with water. Explain why oils are not attracted to water, whereas a substance like NaCl (table salt) is attracted to H2O. Hint: Think of why water molecules are attracted to each other.

37. Which of the following is a unique property of water?
a. |_| cohesion
b. |_| floating as ice
c. |_| being a crucial solvent
d. |_| all of the above

Societal Aspects of Human Gene Editing.

Biology homework help
Topic 1. Societal Aspects of Human Gene Editing. Read the letter-to-the-editor to a newspaper by Dr. Cox, in which he states an opinion about the use of CRISPR for human gene editing.

  • (a) In your own words, what is the main point that Dr. Cox is trying to make?
  • (b) How can our society reconcile differing views about the ethics of using biotechnology? Explain.

Topic 2. Societal Aspects of Gene Drives in Wild Populations. In the article by Zimmer (2017), Kevin Esvelt says that he made a huge mistake by championing the application of a technology that he now says is far too dangerous to actually deploy. In a post of about 125 words, address the following:

  • (a) What is the technology that he championed? What does it consist of and why does he think it’s too risky to use outside the lab?
  • (b) In your opinion, what sorts of laws and regulations, if any, should society put into place to regulate the technology that Esvelt regrets championing?

Topic 3. Pedigrees for Traits that are Controlled by a Single Gene. While most human traits are controlled by more than one gene, a subset of them are controlled by a single gene for that trait. In such cases, the pedigree can be useful in determining the mode of inheritance, such as autosomal dominant, autosomalrecessive, or X-linked recessive. The document Pedigrees.pdf **  contains the pedigree for three different traits from the same family: Trait 1, Trait 2 and Trait 3. In each pedigree, individuals with the trait are shaded. These pedigrees follow the usual conventions for pedigrees: squares are males; circles are female; offspring are drawn under each mating pair. See book for details.

  • (a) Which of the three traits (Trait 1, Trait 2, Trait 3) follows an X-linked recessive pattern of inheritance?
  • (b) Which clues from the pedigree support your conclusion?

References
Cox, J. (2017, October 11). Compromise sure beats division. Courier-Record Newspaper [Blackstone, Virginia], p. A4. Can be found via this link:  cox crisprletter.pdf **
Zimmer, C. (2017, November 16). ‘Gene drives’ are too risky for field trials, scientists say. The New York Times. Retrieved from https://www.nytimes.com/2017/11/16/science/gene-drives-crispr.html?_r=0

Describe the environmental conditions required for coral reef formation

Biology homework help
Week 5 Discussion Board and Quiz

Here are the assigned discussion questions for Week 5:
1) Discuss the adaptations of intertidal organisms for coping with each of the following environmental stressors:
a) Wave shock
b) Temperature variation
c) Oxygen stress
d) Dessication
2) Describe four categories of estuaries based on geomorphology and give an example of each
3) Describe four categories of estuaries based on patterns of water circulation and give an example of each
4) Discuss coral reefs
a) Describe the environmental conditions required for coral reef formation
b) Describe the three main types of coral reefs.
c) Discuss the factors that contribute to high primary productivity in coral reefs
d) Discuss the factors that contribute to high species diversity in coral reefs
5) Define the following terms: euryhaline, stenohaline, osmoconformers, osmoregulators
Using this week’s assigned readings (and maybe an occasional peak at Google) you should be able to find the answers to your assigned discussion question. You must write one original post for your own assigned discussion question and two replies two other students’ posts. Each post should be at least 100 words in length. For full credit, link to a webpage that pertains to the subject. Have fun!
Dr. Hahn
Start a New Thread

Respiratory Syncytial Virus

Biology homework help
Topic: Respiratory Syncytial Virus
This microbe has been in the news in the past year.You must provide a written review a major news article focusing on the  microbe as the primary discussion!Find a media-based, mass-distributed news source where even Grandma gets her news, that reported the microbe within the past year, as the main reference.Use government-based or other scholarly references only as secondary information, to explain details missing above such as, how the organism affects us, or follow -up information not known at the time of the news release but has been provided since that time.
You must write a review of the news article contents, discuss what type of microorganism it is, and if the organism is in nature or is used in industry or causes disease. If it causes disease you must discuss transmission, increasing incidence, factors contributing to the spread of the organism, lab culturing, etc.
the  discussion should be well-written, in your own words, paraphrasing from only credible academic sources. You may not directly quote from your sources.  You must also cite your credible academic reference sources in text and provide full end ref information in APA format. The initial post must be at least 300-400  word