Almost all of the oxygen gas in today’s atmosphere is present as a result of a. outgassing from volcanoes. b. aerobic respiration. c. endosymbiosis. d. photosynthesis.

Question

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Answer 1

Textbook Question

Chapter 18, Problem 1MC

Almost all of the oxygen gas in today’s atmosphere is present as a result of

a. outgassing from volcanoes.
b. aerobic respiration.
c. endosymbiosis.
d. photosynthesis.

Expert Solution & Answer

Summary Introduction

Introduction:

There was no oxygen gas in the primitive atmosphere, so the cells must have metabolized the organic molecules anaerobically. Thus, anerobic bacteria were the earliest cells. Simpler molecules such as water, and carbon dioxide would still be very abundant. Eventually, some cells evolved the ability to utilize the energy of sunlight to carry out the synthesis of high energy complex molecules from simpler molecules releasing oxygen as a byproduct. The emergence of this new method introduced significant amount of oxygen into the atmosphere for the first time.

Answer to Problem 1MC

Correct answer:

Almost all of the oxygen gas in today’s atmosphere is present as a result of photosynthesis. Therefore, option (d) is correct.

Option (d) is given as “photosynthesis”.

Explanation of Solution

Justify reason for the correct statement:

Water based photosynthesis converts carbon dioxide and water to energy-containing molecules of glucose which releases oxygen as a byproduct. This oxygen denotes the significant amount of free oxygen present in the today’s atmosphere.

Hence, option (d) is correct.

Justify reasons for the incorrect statements:

Option (a) is given as “outgassing from volcanoes”.

Outgassing from volcanoes produces hydrogen sulfide. Hence, it is a wrong answer.

Option (b) is given as “aerobic respiration”.

It is utilization of oxygen to break down the food molecules for the release of energy. Thus, this process utilizes and decreases the amount of oxygen in the atmosphere. Hence, it is a wrong answer.

Option (c) is given as “endosymbiosis”

The theory of endosymbiosis proposes the origin of eukaryotic organelles such as chloroplast and mitochondria. Hence, it is a wrong answer.

Hence, options (a), (b), and (c) are incorrect.

Conclusion

Majority of oxygen available in the today’s atmosphere is present as a result of photosynthesis.

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Answer 2

Textbook Question

Chapter 18, Problem 1MC

Almost all of the oxygen gas in today’s atmosphere is present as a result of

a. outgassing from volcanoes.
b. aerobic respiration.
c. endosymbiosis.
d. photosynthesis.

Expert Solution & Answer

Summary Introduction

Introduction:

There was no oxygen gas in the primitive atmosphere, so the cells must have metabolized the organic molecules anaerobically. Thus, anerobic bacteria were the earliest cells. Simpler molecules such as water, and carbon dioxide would still be very abundant. Eventually, some cells evolved the ability to utilize the energy of sunlight to carry out the synthesis of high energy complex molecules from simpler molecules releasing oxygen as a byproduct. The emergence of this new method introduced significant amount of oxygen into the atmosphere for the first time.

Answer to Problem 1MC

Correct answer:

Almost all of the oxygen gas in today’s atmosphere is present as a result of photosynthesis. Therefore, option (d) is correct.

Option (d) is given as “photosynthesis”.

Explanation of Solution

Justify reason for the correct statement:

Water based photosynthesis converts carbon dioxide and water to energy-containing molecules of glucose which releases oxygen as a byproduct. This oxygen denotes the significant amount of free oxygen present in the today’s atmosphere.

Hence, option (d) is correct.

Justify reasons for the incorrect statements:

Option (a) is given as “outgassing from volcanoes”.

Outgassing from volcanoes produces hydrogen sulfide. Hence, it is a wrong answer.

Option (b) is given as “aerobic respiration”.

It is utilization of oxygen to break down the food molecules for the release of energy. Thus, this process utilizes and decreases the amount of oxygen in the atmosphere. Hence, it is a wrong answer.

Option (c) is given as “endosymbiosis”

The theory of endosymbiosis proposes the origin of eukaryotic organelles such as chloroplast and mitochondria. Hence, it is a wrong answer.

Hence, options (a), (b), and (c) are incorrect.

Conclusion

Majority of oxygen available in the today’s atmosphere is present as a result of photosynthesis.

Want to see more full solutions like this?

Subscribe now to access step-by-step solutions to millions of textbook problems written by subject matter experts!

Answer 3

Textbook Question

Chapter 18, Problem 1MC

Almost all of the oxygen gas in today’s atmosphere is present as a result of

a. outgassing from volcanoes.
b. aerobic respiration.
c. endosymbiosis.
d. photosynthesis.

Expert Solution & Answer

Summary Introduction

Introduction:

There was no oxygen gas in the primitive atmosphere, so the cells must have metabolized the organic molecules anaerobically. Thus, anerobic bacteria were the earliest cells. Simpler molecules such as water, and carbon dioxide would still be very abundant. Eventually, some cells evolved the ability to utilize the energy of sunlight to carry out the synthesis of high energy complex molecules from simpler molecules releasing oxygen as a byproduct. The emergence of this new method introduced significant amount of oxygen into the atmosphere for the first time.

Answer to Problem 1MC

Correct answer:

Almost all of the oxygen gas in today’s atmosphere is present as a result of photosynthesis. Therefore, option (d) is correct.

Option (d) is given as “photosynthesis”.

Explanation of Solution

Justify reason for the correct statement:

Water based photosynthesis converts carbon dioxide and water to energy-containing molecules of glucose which releases oxygen as a byproduct. This oxygen denotes the significant amount of free oxygen present in the today’s atmosphere.

Hence, option (d) is correct.

Justify reasons for the incorrect statements:

Option (a) is given as “outgassing from volcanoes”.

Outgassing from volcanoes produces hydrogen sulfide. Hence, it is a wrong answer.

Option (b) is given as “aerobic respiration”.

It is utilization of oxygen to break down the food molecules for the release of energy. Thus, this process utilizes and decreases the amount of oxygen in the atmosphere. Hence, it is a wrong answer.

Option (c) is given as “endosymbiosis”

The theory of endosymbiosis proposes the origin of eukaryotic organelles such as chloroplast and mitochondria. Hence, it is a wrong answer.

Hence, options (a), (b), and (c) are incorrect.

Conclusion

Majority of oxygen available in the today’s atmosphere is present as a result of photosynthesis.

Want to see more full solutions like this?

Subscribe now to access step-by-step solutions to millions of textbook problems written by subject matter experts!

Answer 4

Textbook Question

Chapter 18, Problem 1MC

Almost all of the oxygen gas in today’s atmosphere is present as a result of

a. outgassing from volcanoes.
b. aerobic respiration.
c. endosymbiosis.
d. photosynthesis.

Expert Solution & Answer

Summary Introduction

Introduction:

There was no oxygen gas in the primitive atmosphere, so the cells must have metabolized the organic molecules anaerobically. Thus, anerobic bacteria were the earliest cells. Simpler molecules such as water, and carbon dioxide would still be very abundant. Eventually, some cells evolved the ability to utilize the energy of sunlight to carry out the synthesis of high energy complex molecules from simpler molecules releasing oxygen as a byproduct. The emergence of this new method introduced significant amount of oxygen into the atmosphere for the first time.

Answer to Problem 1MC

Correct answer:

Almost all of the oxygen gas in today’s atmosphere is present as a result of photosynthesis. Therefore, option (d) is correct.

Option (d) is given as “photosynthesis”.

Explanation of Solution

Justify reason for the correct statement:

Water based photosynthesis converts carbon dioxide and water to energy-containing molecules of glucose which releases oxygen as a byproduct. This oxygen denotes the significant amount of free oxygen present in the today’s atmosphere.

Hence, option (d) is correct.

Justify reasons for the incorrect statements:

Option (a) is given as “outgassing from volcanoes”.

Outgassing from volcanoes produces hydrogen sulfide. Hence, it is a wrong answer.

Option (b) is given as “aerobic respiration”.

It is utilization of oxygen to break down the food molecules for the release of energy. Thus, this process utilizes and decreases the amount of oxygen in the atmosphere. Hence, it is a wrong answer.

Option (c) is given as “endosymbiosis”

The theory of endosymbiosis proposes the origin of eukaryotic organelles such as chloroplast and mitochondria. Hence, it is a wrong answer.

Hence, options (a), (b), and (c) are incorrect.

Conclusion

Majority of oxygen available in the today’s atmosphere is present as a result of photosynthesis.

Want to see more full solutions like this?

Subscribe now to access step-by-step solutions to millions of textbook problems written by subject matter experts!

Answer 5

Textbook Question

Answer 6

Textbook Question

Answer 7

Expert Solution & Answer

Summary Introduction

Introduction:

There was no oxygen gas in the primitive atmosphere, so the cells must have metabolized the organic molecules anaerobically. Thus, anerobic bacteria were the earliest cells. Simpler molecules such as water, and carbon dioxide would still be very abundant. Eventually, some cells evolved the ability to utilize the energy of sunlight to carry out the synthesis of high energy complex molecules from simpler molecules releasing oxygen as a byproduct. The emergence of this new method introduced significant amount of oxygen into the atmosphere for the first time.

Answer to Problem 1MC

Correct answer:

Almost all of the oxygen gas in today’s atmosphere is present as a result of photosynthesis. Therefore, option (d) is correct.

Option (d) is given as “photosynthesis”.

Explanation of Solution

Justify reason for the correct statement:

Water based photosynthesis converts carbon dioxide and water to energy-containing molecules of glucose which releases oxygen as a byproduct. This oxygen denotes the significant amount of free oxygen present in the today’s atmosphere.

Hence, option (d) is correct.

Justify reasons for the incorrect statements:

Option (a) is given as “outgassing from volcanoes”.

Outgassing from volcanoes produces hydrogen sulfide. Hence, it is a wrong answer.

Option (b) is given as “aerobic respiration”.

It is utilization of oxygen to break down the food molecules for the release of energy. Thus, this process utilizes and decreases the amount of oxygen in the atmosphere. Hence, it is a wrong answer.

Option (c) is given as “endosymbiosis”

The theory of endosymbiosis proposes the origin of eukaryotic organelles such as chloroplast and mitochondria. Hence, it is a wrong answer.

Hence, options (a), (b), and (c) are incorrect.

Conclusion

Majority of oxygen available in the today’s atmosphere is present as a result of photosynthesis.

Answer 8

Expert Solution & Answer

Summary Introduction

Introduction:

There was no oxygen gas in the primitive atmosphere, so the cells must have metabolized the organic molecules anaerobically. Thus, anerobic bacteria were the earliest cells. Simpler molecules such as water, and carbon dioxide would still be very abundant. Eventually, some cells evolved the ability to utilize the energy of sunlight to carry out the synthesis of high energy complex molecules from simpler molecules releasing oxygen as a byproduct. The emergence of this new method introduced significant amount of oxygen into the atmosphere for the first time.

Answer to Problem 1MC

Correct answer:

Almost all of the oxygen gas in today’s atmosphere is present as a result of photosynthesis. Therefore, option (d) is correct.

Option (d) is given as “photosynthesis”.

Explanation of Solution

Justify reason for the correct statement:

Water based photosynthesis converts carbon dioxide and water to energy-containing molecules of glucose which releases oxygen as a byproduct. This oxygen denotes the significant amount of free oxygen present in the today’s atmosphere.

Hence, option (d) is correct.

Justify reasons for the incorrect statements:

Option (a) is given as “outgassing from volcanoes”.

Outgassing from volcanoes produces hydrogen sulfide. Hence, it is a wrong answer.

Option (b) is given as “aerobic respiration”.

It is utilization of oxygen to break down the food molecules for the release of energy. Thus, this process utilizes and decreases the amount of oxygen in the atmosphere. Hence, it is a wrong answer.

Option (c) is given as “endosymbiosis”

The theory of endosymbiosis proposes the origin of eukaryotic organelles such as chloroplast and mitochondria. Hence, it is a wrong answer.

Hence, options (a), (b), and (c) are incorrect.

Conclusion

Majority of oxygen available in the today’s atmosphere is present as a result of photosynthesis.

Answer 9

Expert Solution & Answer

Answer 10

Expert Solution & Answer

Answer 11

Summary Introduction

Introduction:

There was no oxygen gas in the primitive atmosphere, so the cells must have metabolized the organic molecules anaerobically. Thus, anerobic bacteria were the earliest cells. Simpler molecules such as water, and carbon dioxide would still be very abundant. Eventually, some cells evolved the ability to utilize the energy of sunlight to carry out the synthesis of high energy complex molecules from simpler molecules releasing oxygen as a byproduct. The emergence of this new method introduced significant amount of oxygen into the atmosphere for the first time.

Answer 12

Answer to Problem 1MC

Correct answer:

Almost all of the oxygen gas in today’s atmosphere is present as a result of photosynthesis. Therefore, option (d) is correct.

Option (d) is given as “photosynthesis”.

Answer 13

Explanation of Solution

Justify reason for the correct statement:

Water based photosynthesis converts carbon dioxide and water to energy-containing molecules of glucose which releases oxygen as a byproduct. This oxygen denotes the significant amount of free oxygen present in the today’s atmosphere.

Hence, option (d) is correct.

Justify reasons for the incorrect statements:

Option (a) is given as “outgassing from volcanoes”.

Outgassing from volcanoes produces hydrogen sulfide. Hence, it is a wrong answer.

Option (b) is given as “aerobic respiration”.

It is utilization of oxygen to break down the food molecules for the release of energy. Thus, this process utilizes and decreases the amount of oxygen in the atmosphere. Hence, it is a wrong answer.

Option (c) is given as “endosymbiosis”

The theory of endosymbiosis proposes the origin of eukaryotic organelles such as chloroplast and mitochondria. Hence, it is a wrong answer.

Hence, options (a), (b), and (c) are incorrect.

Answer 14

Conclusion

Majority of oxygen available in the today’s atmosphere is present as a result of photosynthesis.

Answer 15

Ch. 18.1 - How Would the experiments result charge if oxygen...Ch. 18.1 - describe a likely scenario for the origin of life?Ch. 18.1 - describe, for each step in the scenario, some...Ch. 18.2 - Uranium-235, with a half-life of 713 million...Ch. 18.2 - Scientists have identified a free living bacterium...Ch. 18.2 - describe scenarios for the major evolutionary...Ch. 18.2 - State the order in which these events occurred,...Ch. 18.3 - describe fossil evidence of the earliest...Ch. 18.3 - describe the advantages that fostered the origin...Ch. 18.3 - Prob. 3CYL

Almost all of the oxygen gas in today’s atmosphere is present as a result of a. outgassing from volcanoes. b. aerobic respiration. c. endosymbiosis. d. photosynthesis.

Solution Summary: The author explains that anerobic bacteria metabolized organic molecules anaerobically, thereby introducing oxygen into the atmosphere for the first time.

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