Reference no: EM133201414

1. Stromatolites found in the coasts of Australia have cyanobacteria that can conduct photosynthesis, but they had initially started their life evolving in an atmosphere that was devoid of oxygen, thus an anerobic environment.. Answer the following questions with brief reasoning in every answer:

a) What is the metabolic process in the present aerobic environment that cynaobacteria would have not been able to perform in their anerobic ennvironment?

b) What are the cellular organelles that cyanobacteria would have "acquired" during their evolution from anerobic to aerobic atmosphere? If yes or no, explain your reason.

c) Which photosynthetic process would be ideal for cyanobacteria a C3 or C4 cycle? Explain your reason.

d) Will the initial absence of oxygen in atmosphere have affected the metabolic processes in cyanobacteria? Give reasons.

2. Glucose metabolism in the metabolic world would have been different from the seamless process of glycolysis and citric acid cycle that we see today. The atmosphere in the primordial worldwould have developed high acidic levels that slow their capacity to do work and generate energy. Utlizing your knowledge of biochemistry involved in life processes, answer the following questions:

a) What is the compound that accumulates in an acidic atmosphere, and which metabolic process would produce this compound?

b) In an acidic anerobic atmosphere, what is the specific name of the reaction, and what caused it later to evolve into the citric acid cycle?

c) How would organisms in the primordial world survive without citric acid cycle? Explain your answer.

d) How did endosymbiosis help in evolving the citric acid cycle?

3. When you lose weight, you essentially burn fats. The fats or triglycerides, enter muscle and liver cells where they are taken apart to form a substance X. Within an important cell organellethe substance X combines with substance Y to form Substance Z. This kicks off an important metabolic pathway. The weight of fats is thus lost in the form an important compound. Answer the following questions related to the life process detailed above:

a) Name the substances, X, Y and Z.

b) What is the important metabolic pathway kicked off by Substance Z and what is the cell organelle involved?

c) The weight lost by burning of fats is resulting in the formation of an important compound.What is the compound, and what is its role in life?

d) Certain by products in the metabolic pathway are released by lungs and skin. What are these by-products, and what do they do when they are being removed?

4. The Biochemist Nick Lane observed hydrothermal vents that opened a world of primordial life that mirrored origins of earth. One of the phenomemon that was observed was a "proton gradient" that fueled metabolic reactions. Answer the following questions:

a) What is one of the important metabolic phenomenon or concept that you learned in class that causes the proton gradient?

b) In a concept you learned in class, what metabolic process or processes would the proton gradient induce?

c) How can the above phenomenon be used to understand processes that cause cancer?

d) Can the phenomenon observed by Nick Lane help us understand and improve the current unwanted climate change that is threatening the environment ?

5. Mitochondria and chloroplasts were once free-living bacteria that later migrated into eukaryotic cells. Mitochondria make energy while chloroplasts prepare their own food.

a) How can a mitochondrion live by itself? Explain your answer by mentioning the specific processes that this organelle performs.

b) What does a chloroplast do to survive in its free-living condition? What important chemicals does it need froma sorrounding primordial soup to prepare its own food?

c) Apart from the process by which chloroplasts prepare their own food, what other vital process protects it from dying in an acidic environment?

d) The DNA inside these organelles would have helped them make their own proteins. But, now inside eukaryotic cells, they do not make proteins. So after moving into the eukaryotes, what are the cellular structures that dissapeared? (Clue: these are involved in protein synthesis both in bacteria and higher life forms).