Chemical Levels of Organization Quiz Review

Homeostasis

the ability of an organism to maintain a stable internal environment in the face of constant change

mechanisms of homestasis

auto regulation

extrinsic regulation

autoregulation

organ fixes the problem itself

extrinsic regulation

the brain steps in to help regulate

3 step process of homeostasis

1. receptor

2. integrating center

3. effector

positive feedback

intensifies change in the same direction as the original change

negative feedback

NOTES

elements

substance made from one kind of atom, cannot be broken down into other substance through chemical reactions

essential elements of life

25/92 and the big 8

carbon

hydrogen

nitrogen

oxygen

96%

calcium

phosphorus

potassium

sulfur

4%

trace elements

those elements required in small amounts by an organism (e.g. iodine)

compounds

a substance consisting of 2 or more elements in a fixed ratio

formed via covalent or ionic bonds

inorganic and organic

organic compounds

contain hydrogen and carbon

inorganic compounds

do NOT contain hydrogen with carbon

h2o, co2, o2

the 4 emergent properties of water

solvent

lubricant

high hear capacity

reactivity

reactivity of water

dehydration synthesis

hydrolysis

2 compartments of water

NOTES

neutrons

mass # - atomic #

valence shell/ valence electrons

outermost electrons

the chemical behavior of an atom is mostly determined by its valence electrons, determined by the distribution of electrons in electron shells

atoms are always seeking to fill their outer shells

innermost shell holds 2, each subsequent shell holds only up to 8

shells are filled through bonding

chemical bonding