Chapter 1: Light and Life

Light
- source of information and energy
- Defined as EM radiation
- Wave of photons
- Can be absorbed by pigments and then used
- Colour = light that is not absorbed by pigment
Electrons become excited when absorbed by light which in turn then becomes potential energy (photosynthesis)
Photoreceptor
- light-sensing system
- made up of pigment molecule bound to protein
- eye = organ of animals to sense light
Problem:
- most light driven processes can only process a certain part of the EM spectrum
- source of energy…too much can cause deadly effects
- pigment melanin in our skin absorbs UV (high energy and can be damaging)
Circadian rhythms (body clock) the daily cycle of most living organisms have evolved to adapt to the change in light (night and day…plant use photosynthesis during the day and night break glucose)
Some animals prefer the dark (nocturnal animals like moths)
Some animals have ancestors that had functional eyes but are not blind (blind mole rat)
bioluminescent: organisms that use chemical energy to make their own light to attract a mate, camouflage, attract prey or communicate

Chapter2: origins of Life

Display order: high ordered structures
Harness and utilize energy: getting and using chemical energy to power the organism’s activities
Reproduce: ability to reproduce their own kind
Respond to stimuli: ability to respond environmental stimuli
Exhibit homeostasis: ability to control an organism’s internal environment within the limits to sustain life
Growth and development: consistent growth and development (DNA inheritance)
Evolve: adapt to environments over many generations to have better reproducibility and survival of the species.