Carbon*

Hydrogen

Oxygen

Nitrogen

Sulfur

Phosphorus

CARBON is central to life

Life is:

- Water Based

- Carbon-based

- Self Organizing/regulating (homeostasis)

- Self-replicating (reproduction)

- Living organisms make new living organisms that are identical/similar to themselves

- Life Changes (evolves) over generations

- Living organisms alter their environment

Energy

- Mostly comes from sunlight

Become less complex

ex: universe runs downhill, becoming less complex

- The reverse of entropy requires energy

Less complex ---> More complex

Example: Assemblage of carbon dioxide and water into carbohydrates by plants happens through capturing the energy from sunlight: PHOTOSYNTHESIS

- The recipe/instructions/coding for life

- instructions for how to make the complex structure of an organism from elements and simple compounds

- replicated prior to reproductions, and copies passed to offspring

- called "genetic material"

- has evolved over time

- occurs when living organism changes in response to changes in their environment

examples:

- resiliency of bacteria in the face of manmade antibiotics

- Solver foxes: docile, tolerant, domesticated foxes with shorter tailes, snouts and smaller ears (infantalized features)

- radioisotope dates earth to 4.5 billion years old.

- life existed on earth for 3.5 billion years and has changed dramatically

- First organisms were prokaryotic bacteria

- more complex org. appeared 2.2 million years ago (eukaryotic)

- animals appeared .6 billion years ago

- implies change in DNA! (DNA evolves!)

- dramatic alteration in the environment that occured 2.5 billion years ago

- appearance of photosynthetic bacteria (cyanobacteria) led to increase in oxygen in the atmosphere

- abundance of oxygen was toxic to the indigenous anaerobic bacteria 

- some bacteria evolved a resistance to O, and some began to use it in their metabolism

- O-based metabolism more efficient than O-free metabolism, and supported more complex organisms (eukaryotics), eventually humans

- organisms that are more complex than bacteria are oxygen-dependent (protozoa, fungi and animals)

- basic unit of life

- small, usually surrounded by membrane (plasma membrane)

- smalles entity that has properties of life: reproduction, organization, environmental alteration, DNA, self-regulation using DNA

- Complex life is multicellular (ex: humans)

1. Prokaryotes: outer membrane is only membrane (bacteria)

2. Eukaryotes: additional structures outside of membrane (nucleus)