Lecture 2 - The Chemical Basis of Life Lavoisier(1743-1794...

Info icon This preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon
The Chemical Basis of Life Lavoisier (1743-1794) - noted the relative chemical simplicity of the mineral world and contrasted this with the complexity of the plant and animal worlds The latter were composed of compounds rich in the elements carbon , hydrogen , oxygen , nitrogen , sulfur , and phosphorous ( the six most abundant elements in living systems ) Early 20th century biochemical investigations of glucose breakdown in yeast and animal muscle cells revealed remarkable chemical similarities Jacques Monod - What is true of E. coli is true of an elephant The current understanding that all organisms share a common evolutionary origin is based, in part, on our biochemical unity Biochemical Unity - the biochemical composition ( make-up ) of all organisms is astoundingly similar
Image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
The Chemical Basis of Life Fewer than 30 of the more than 90 naturally occurring chemical elements are essential to all organisms Bulk elements shaded in orange are structural components of all cells and tissues and are required in the diet in gram quantities Trace elements shaded in yellow are required in much smaller quantities (<< a few milligrams )
Image of page 2
Carbon Chemistry Chemistry of living organisms revolves around carbon Carbon accounts for more than half the dry weight of cells C can form single bonds with hydrogen atoms, and single and double bonds with oxygen and nitrogen atoms Of greatest significance for biological systems is the ability of carbon to form very stable single bonds with up to four other carbon atoms Two carbon atoms can share two (or three) electron pairs, thus forming double (or triple) bonds The reason for this is that carbon, with an atomic number of 6, has a valency of 4, i.e. requires 4 electrons to fill its outer shell
Image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 4
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern