Concepts in Biochemistry

A unique feature of the eukaryotic cell is the compartmentation of cellular compartments and, therefore, the compartmentation of biological function. (p. 21)

Comment: Organizational structure is also key to effective systems.

Biochemistry has three major themes: Structure and function of molecules, information processing and energy transfer. (p. 23)

Comment: So is human society. Structure and function of organizations, information processing and energy transfer.

Some thought: Computer, 2 digit, human use, 10 digit. DNA 4 bases. Protein, 20 amino acids. The ratio 2:10 = 4:20. Coincidence or some economic principle behind it. Think more about it.

Question: Why transcript to a RNA from a DNA? Why cannot use DNA directly or another DNA segment?

Partial answer: RNA preceded DNA. It is from RNA that DNA evolved. But we still need to answer why DNA take over everything. Another question is that why base U in RNA becomes base T in DNA.

pH = -log[H+], another example of the same formula

Fruit juices are acidic chemically. Why they are called basic?

Understand how different pH levels at different organs help their function. For example, stomach is very acidic, which helps it break down food molecules in digesting. Why muscle is acidic while blood and liver are basic? How different pH levels are maintained inside body?

In society, some positions are long term, some are short. Some commodities, mostly unimportant, are traded in open market with little government intervention. Some commodities, such as oil, uranium, which are important, are heavily influenced by government negotiations and military interventions. There is no such a thing as pure market.

Viruses cannot exist independently and are usually not considered as forms of life. (p. 307)

Comment: This applies to every form of life. Plants cannot exist independently from the sun and animals cannot exist independently from the plants. As long as there is an economic system whose cost is less than its gain, it should be considered life.

Question: Why tRNA is needed in protein synthesis? Why not use mRNA directly?

Possible answer. One mRNA can be simultaneously used as a template for many proteins. This will speed up protein synthesis. Check if this is the correct understanding.

Question: Why ribosomes constitute two subunits? Is it because of historical reason?