Definition of life Order: cellular structure Crystals have structure without life.

Definition of lifeOrder: cellular structure

Crystals have structure without life

reproduction

Growth & development

Energy utilization

Response to the environment

Evolution

Darwin

Adaptation

Darwinian theory of evolutionOver production

Individual variations

Natural selection

75% of population perished in one storm

predators prey

Artificial selection

Composition of cells

Organic molecules:Carbon is a versatile chemical element

Water & oxygen

Difficulties with other elements

Weak bonds

No double bonds

Molecular components Carbohydrates: 2H/O sugar, starch, cellelus. glucos C6H12O6

Lipids: fatty acidStore energy for cells

Proteins: large molecules

Nucleic acids: DNA (deoxyribonucleic acid) & RNA (ribonucleic acid)Store structural information

Built on amino acids. Enzymes & catalystsRegulate reaction ratesBuild structures

Provide energy to cellsfibers

Two basic cell typesProkaryotic cells: No distinct nucleusSingle cell species eg E coli or Salmonelia

Eukaryotic cells: Both single cell (amkebas) complex species (plants, animals)

Biological tree of life: five kingdomsBased on cell structures

Drawin’s notes

RNA tree of life: three domainsBased on molecular structure

The chemistry of life

Metabolism: chemistry of life regulates reaction rates

Atp(adenosine triphosphate)

Metastable reaction

+H2O

Carbon and energy

Heterotroph: get carbon fromother organic compounds Autotroph: get carbon directly from the atmosphere

Photosynthesis: sun light provides a source of energy, CO2

Chemoheterotroph: organic molecules

Chemoautotroph: inorganic chemicals, eg sulfur, iron, amonia. CO2

Carbon is the most common raw material

Importance of water1) Dissolving organic molecules

2) transportation

3) ATP chemistry

Double helix of DNA molecules

Gene’s analysis

DNA replication

Genetic code

Virus (a strand of RNA, not alive)Coronavirus: common cold, SARS

Mutation and evolution

extremofilesThermofiles