From Biolk483

Revision as of 02:11, 11 September 2006

Introduction / Information

Dr. Stillwell

• First taught biochemistry in 1980
• Membrane biophysics (structure and function) is his specialty
• He is an editor of a journal that sees 400+ abstracts each year and excepts about 30.
• He is writing a textbook on membranes.
• He has terrible health, especially his eyes.

Exams

• There will be three exams
• The first exam will be mid-October and will cover some of proteins.
• The second exam will be near Thanksgiving.
• Both Exam 1 and Exam 2 are worth 100 points each; the final is worth 200 points.
• He has the hardest exams ever:
  • The first exam usually sees an average of about 44-49% (class average).
  • The second exam is generally around at 50% class average.
• Overall class grade of 65% gets curved up to an 'A', generally.
• Exams are only over class notes!
• Exams are only over class notes!!
• Exams are only over class notes!!!
• The multiple choice sections are the hardest.

Generally Good Ideas

• Do not get behind.
• Make study groups.
• Recopy notes...perhaps by putting them up on this wiki. :)
• Dr. Stillwell has no office hours; come in whenever.

Lecture

The generations of biochemists

1. 1st generation: studied metabolism
2. 2nd generation: studied molecular biology
3. 3rd generation: study dynamics of biology (at the single molecule level)
   

• Generalization of biochemistry: the study of composition, organization, structure and function.
• Wohler started this whole business of biochemistry when he used ammonium cyanide to make urea --a product believed at the time to only be producible by living things (which ammonium cyanide obviously is not). This meant that man may be capable of doing reactions much like what occurs in the body.
• Insert paper handout here
• We can only look for life assuming it is similar to life on Earth (has "the thread of life").
  • There is only one thread we know, only one origin.
  • CHON = the elements here and elsewhere in the solar system.
• Why is water so important, we'll we'll talk about that next week.
• We cannot imagine life without water, so we assume it is necessary
  • Second most abundant (non-man-made) liquid is mercury (Hg).
• Rock has been found that was made by bacteria that lives in sulfuric acid.
• Europa: a moon of Jupiter; an enormous ball of ice which gravity causes it to crack, then fluid spews up through the cracks and we see that it is yellow. This makes us think it has organic material in it.
• Even if water isn't really necessary for life, we probably won't recognize a form of life that doesn't use water.

Thread of Life

• Time frame parameters for life
  • if it moves too slow we won't be around long enough to observe that it is dynamic; if it is too fast we don't see that it is self-controlled and purposeful. Either way, we probably wouldn't recognize forms of life at the extremes of a time scale.
  • we have to use catalysts to make our reactions happen at the correct rate, so we imagine that most forms of life do, also.
• Information storage
  • we imagine that all forms of life need something like DNA to keep and pass along information.
• Energy currency
  • most forms of life we know use ATP as the energy currency; we imagine that all living things have some sort of comparable currency.
• Barrier
  • membranes, life probably needs them.
• Limit to the size of single cells
  • There is an upper bound on the size of a single cell because of the rate of diffusion of water. If you assume that each cubic unit necessitates a certain amount of water, then as a cell expands, it becomes harder and harder to get enough water in and out of the cell to fulfill these water demands as surface area does not increase as rapidly as volume in expansion.
• Polymers
  • we see that we have many different polymers and assume that most forms of life require such tools.