Structure of Life

Elements of Life  90 Natural occurring elements, 25 essential  96% of the mass of a human is made up of C, O, H, N

Molecules of Life  Molecule: a group of atoms held together by covalent bonds Example: H2O 25 essential elements Page 146 Picture: a ferritin homolog that binds and protects DNA

Water  Most important compound in living organisms.  It serves as a transport of materials, and as a reservoir for process to occur.  It has several unique properties Polar, resists temperature change, water expands when it freezes

Proteins  Provide structure for tissue and organs and carry out cell metabolism.  Metabolism: all the chemical reactions that occur within an organism.  The basic building blocks are amino acids (a.a.) A structural building block of many organism

Protein Cont.  Important for contraction of muscle tissue, transporting oxygen in the blood stream, providing immunity, regulation of proteins, and carrying out reactions.  Example: Enzyme

Enzyme

Carbohydrates  Used by cells to store and release energy  Organic-has carbon  An organic compound composed of C, H, and O with a ratio of 2H:1O:1C  Different types: monosaccharide, disaccharide, polysaccharide

Carbohydrate

Lipids  Cells use lipids for energy storage, insulation, and protective coatings.  Major components of the membrane that surround all living cells  Organic coumpound

Nucleic Acids  A complex macromolecule that stores cellular information in the form of a code  smaller subunits are nucleotides

Explain  “With the cell, Biology discovered its atom.”

 Atom is the basis for the element. Just like the cell is the basis for biology.  Cells are the basic unit for Biotic organism.

Technology 1. Light microscope Simple light microscope, contained one lens and used natural light to view objects * Similar to dissecting microscopes

Technology Cont.  Compound Microscope  Use a series of lenses to magnify objects in steps (magnify 1500X)  Uses artificial light

Images: Meiosis

Image: Earthworm

Technology Cont. 3. Electron Microscope  Use a beam of highly energetic e- to examine objects on a very fine scale (instead of light)

Electron Microscope Cont.

Image: Mosquito

Cont.  The compound microscope can magnify up to 1500X  The electron microscope can magnify up to 500,000 X

Scientists can now begin to draw conclusions about the organization of living matter

Size, Shape, and Number  It’s important to understand that cells vary in size and shape depending on their functions!

Differentiation  The structural adaptation of some body part for a particular function. There’s a lot of different functions for all the different cells.  Some functions are: blood cells, skin cells, brain cells, etc…  Differentiation is usually expressed stating how different tumor cells are from the cells from which they originated.