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Apr 15 2017 07:24pm
So, there are 20 chapters to choose from and you cannot choose more than 2 questions for each chapter. Looking for originally worded answers – if I copy and paste what you send me into google and it comes back word for word, that obviously doesn’t work. :)

Shoot me a PM if you’re interested - serious inquiries needed ASAP. Technically this needs to be done before Tuesday morning, but I'd like to be done by Monday night.

Thanks.

Here are the questions from the first half - will post the second batch of chapters/questions shortly.

Chapter 1

In what ways does evolution depend on transfer of information? In what ways does transfer of information depend on evolution?

How might an understanding of evolutionary processes help a biologist doing research in (a) the development of a new antibiotic to replace one to which bacteria have become resistant? (b) conservation of a specific plant in a rain forest?

Chapter 2

A hydrogen bond formed between two water molecules is only about 1/20 as strong as a covalent bond between hydrogen and oxygen. In what ways would the physical properties of water be different if these hydrogen bonds were stronger (e.g., 1/10 the strength of covalent bonds)? What if hydrogen bonds were weaker (e.g., 1/100 the strength of covalent bonds)

Scientists have proposed various initiatives to detect water vapor, as well as oxygen and carbon dioxide, in the atmospheres of distant planets. Which of these biosignatures (chemical markers that are evidence for life) would you consider the most fundamental indicator that life could have evolved on these planets? Explain your reasoning

Chapter 3

Like oxygen, sulfur forms two covalent bonds. However, sulfur is far less electronegative. In fact, it is approximately as electronegative as carbon. How would the properties of the various classes of biological molecules be altered if you were to replace all the oxygen atoms with sulfur atoms?

Hydrogen bonds and van der Waals interactions are much weaker than covalent bonds, yet they are vital to organisms. Explain, providing some specific examples.

In what ways are all species alike biochemically? Identify some ways in which species may differ from one another biochemically. What do these similarities and differences suggest about the history of life on Earth?

The total number of possible amino acid sequences in a polypeptide chain is staggering. Given that there are 20 amino acids, potentially there could be 20^100 different amino acid sequences just for polypeptides only 100 amino acids in length. However, the actual number of different polypeptides occurring in organisms is only a tiny fraction of this potential. What insight does this finding provide into the evolutionary process?

Each amino acid could potentially exist as one of two possible enantiomers, known as the D-form and the L-form (based on the arrangement of the groups attached to the asymmetric a carbon). However, in all organisms, only L-amino acids are found in proteins. What does this suggest about the evolution of proteins?

Chapter 4

Why does a eukaryotic cells need both membranous organelles and fibrous cytoskeletal components? Justify your answer.

What types of similarities in cell structure and function tell biologists about the common origin of organisms? Explain.

Chapter 5

GLUT 4 is a glucose transporter that functions in adipose (fat) cell plasma membranes. An analysis of the adipose cells exposed to insulin showed that a single cell could import glucose at a maximum rate of about 1 x 10^8 molecules/second. Under the same conditions, unstimulated cells could only transport a maximum of about 1 x 10 ^7 molecules/second. What does this finding tell you about the relative number of GLUT 4 transporters function in the plasma membranes of stimulated versus unstimulated cells?

Most adjacent plant cells are connected by plasmodesmata, whereas only certain adjacent animal cells are connection through gap junctions. What might account for this difference?

Explain to your roommate why the evolution of biological membranes was an essential step in the origin of life. Give arguments supporting (or challenging) this hypothesis.

Transport proteins have been found in all biological membranes. What hypothesis could you make regarding whether these molecules evolved early or later in the history of cells? Argue in support of your hypothesis.

Chapter 7

All organisms use ATP/ADP as central links between exergonic and endergonic reactions. What does that suggest about the evolution of energy metabolism?

Some have argued that “evolution is impossible because the second law of thermodynamics states that entropy always increases; therefore natural processes cannot give rise to greater complexity.” In what ways is this statement a misunderstanding of the laws of thermodynamics?

You are performing an experiment in which you are measuring the rate at which succinate is converted to fumarate by the enzyme succinic dehydrogenase. You decide to add a little malonate to make things interesting. You observe that the reaction rate slows markedly and hypothesize that malonate is inhibiting the reaction. Design an experiment that will help you decide whether malonate is acting as a competitive inhibitor or a noncompetitive inhibitor.

Chapter 8

Explain why the proton gradient formed during chemiosmosis represents a state of low entropy.

How are the endergonic reactions of the first phase of glycolysis coupled to the hydrolysis of ATP, which is exergonic? How are the exergonic reactions of the second phase of glycolysis coupled to the endergonic synthesis of ATP and NADH?

Could the inner mitochondrial membrane carry out its functions in the coupling of electron transport and ATP synthesis if its lipid bilayer were readily permeable to hydrogen ions (protons)?

Draw a simple sketch illustrating an inner mitochondrial membrane that is actively involved in chemiosmosis and label the two compartments it separates. Add the ATP synthase complex, indicate the proton gradient, and specify in which compartment ATP is synthesized.

The reactions of glycolysis are identical in all organisms – prokaryotes, protists, fungi, plants, and animals that obtain energy from glucose catabolism. What does this universality suggest about the evolution of glycolysis?

Molecular oxygen is so reactive that it would not exist in Earth’s atmosphere today if it were not constantly replenished by organisms that release oxygen as a waste product of photosynthesis. What does that fact suggest about the evolution of aerobic respiration and oxygen-releasing photosynthesis processes?

Chapter 9

What would life be like for photoautotrophs if there were no chemoheterotrophs? For chemoheterotrophs if there were no photoautorophs?

Propose an explanation for bacteria, chloroplasts, and mitochondria all having ATP synthase complexes.

What strategies may be employed in the future to increase world food supply? Base your answer on your knowledge of photosynthesis and related processes.

Chapter 10

How does mitosis provide evidence for relationships among eukaryotes as diverse as mammals and seaweeds?

Some organisms – for example, certain fungi – reproduce asexually when the environment is favorable and sexually when the environment becomes unfavorable. What might be the evolutionary advantage of sexual reproduction with the associated process of meiosis during unfavorable conditions?
Member
Posts: 6,358
Joined: Apr 9 2007
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Apr 16 2017 08:28pm
Eh, nevermind.
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