Lecture 4: Earth's Physical Systems: Matter, Energy, and Geology

Bioremediation =

pollution cleanup through enhanced natural biodegradation

Matter =

all material in the universe that has mass and occupies space

Element =

a fundamental type of matter, with a given set of properties

atoms =

the smallest components that maintain an element’s chemical properties

atom’s nucleus has

• protons (positively charged particles) \n • neutrons (no electric charge)

Atomic number =

number of protons

Electrons =

negatively charged particles surrounding the nucleus

Isotopes =

atoms with differing numbers of neutrons

mass number =

combined number of protons and neutrons

some isotopes are

radioactive \n • emit high-energy radiation

Half-life =

the amount of time it takes for one-half of the atoms \n to give off radiation and decay

Carbon-14 (14C)

5730 years

Molecules =

combinations of two or more atoms

Compounds =

A molecule composed of atoms of two or more different elements

water =

two hydrogen atoms bonded to one oxygen atom: H20

carbon dioxide =

one carbon atom with two oxygen atoms: CO2

Covalent bond =

(SHARING) atoms in a molecule share electrons

Non-polar covalent bonds =

electrons shared equally

Polar covalent bonds =

Atoms share electrons unequally, with one atom exerting a greater pull

Ionic bonds =

an electron is transferred from one atom to another \n – are not molecules, but are salts, such as table salt, NaCl

Hydrogen bond =

oxygen from one water molecule attracts hydrogen atoms of another

Water’s strong

cohesion allows nutrients and waste to be transported

Water absorbs

heat with only small changes in its temperature \n – stabilizes systems

The pH scale ranges from

0 to 14 and quantifies the acidity of solutions

acidic solutions have a pH

less than 7

basic solutions have a pH

greater than 7

neutral solutions have a pH

of 7

Organic Compounds =

carbon atoms joined by covalent bonds and may include other elements \n – such as nitrogen, oxygen, sulfur, and phosphorus

Hydrocarbons =

contain only carbon and hydrogen \n – simplest hydrocarbon is methane \n – hydrocarbons can be a gas, liquid or solid

Polymers =

long chains of repeated molecules \n – the building blocks of life

Macromolecules =

large-size molecules

3 types of polymers are essential to life

• proteins \n • nucleic acids \n • carbohydrates \n – Lipids (are not polymers, but very essential)

Cation

give away electrons and are always positive

Anion=

receives electrons and are always negative

proteins Produce

tissues, provide structural support, store and others transport energy

Deoxyribonucleic acid (DNA) and Ribonucleic Acid (RNA):

carry the hereditary information of organisms \n – long chains of nucleotides that contain \n • sugar, phosphate, and a nitrogen base

Information in DNA is

rewritten to RNA

RNA directs

amino acid assembly into proteins

Genes =

regions of DNA that code for proteins that perform certain functions

Genome =

an organism’s genes \n – divided into chromosomes

Carbohydrates =

consist of atoms of carbon, hydrogen, and oxygen

sugars =

simple carbohydrates \n • glucose = provides energy for cells

complex carbohydrates build structures and store energy \n • starch =

a complex carbohydrate

Lipids =

a chemically diverse group of compounds \n grouped together because they don’t dissolve in \n water \n – for energy, cell membranes, structural support, and \n steroids

Plastics =

synthetic (human-made) polymers \n – best known by their brand names (Nylon, Teflon, \n Kevlar)

Cell =

the basic unit of life’s organization

Eukaryotes =

– multi-celled organisms containing \n internal structures (organelles) \n • Ex: mitochondria, nucleus, Golgi \n apparatus, etc. \n – Include plants, animals, fungi, protists

Prokaryotes =

– single-celled organisms lacking \n organelles and a nucleus \n • Ex: bacteria

Cell theory

all cells come from pre existing cells

Energy =

that which can change the position, physical composition or temperature of matter

Potential energy =

energy of position

Kinetic energy =

energy of motion

Chemical energy =

potential energy held in the bonds between atoms

Potential energy is changed into

kinetic energy to produce motion, action, and heat

First law of thermodynamics =

energy can change forms, but cannot be created or destroyed

Second law of thermodynamics =

the nature of energy changes from a more-ordered to a less-ordered state

Entropy =

an increasing state of disorder

An energy source’s nature determines

how easily energy can be harnessed

Organisms maintain life by

consuming energy

The sun releases radiation from the

electromagnetic spectrum \n – some is visible light

Solar energy

drives weather and climate, and powers plant growth

Autotrophs (primary producers) =

organisms such as green plants, algae and cyanobacteria \n produce their own food from the sun’s energy

Photosynthesis =

the process of turning light energy from the sun into chemical energy \n – Carbon dioxide + water + sun’s energy is converted \n into sugars

Hydrothermal vents =

host entire communities that thrive in high temperature and \n pressure \n – lack of sun prevents photosynthesis

Chemosynthesis =

uses energy in hydrogen sulfide to produce sugar \n 6CO2 + 6H20 + 3H2S C6H12O6 + 3H2SO4

Movement of these plates influences

climate and evolution

Divergent plate boundaries

– Magma rises to the surface \n – Pushing plates apart \n – Creating new crust \n – Has volcanoes and \n hydrothermal vents

Transform plate boundaries

– Two plates meet, slipping and \n grinding \n – Friction spawns earthquakes \n along strike-slip faults

We can decrease impacts of hazards through

technology, engineering, and policy

Mitigating climate change may

reduce natural hazards

Which of the following describes a property of pure water?

can hold many molecules in solution

The force driving plate tectonics is

heat in the deepest layers of the earth

Earthquakes result from

energy released from movement at plate boundaries and faults

Atomic mass

is defined as the number of protons plus the number of neutrons

Which of the following reactions represents cellular respiration?

glucose + oxygen -> water + carbon dioxide + energy

Lipids

are the primary water-insoluble components of cell membranes.

A solution with a pH of 3 is

100 times more acidic a solution with a pH of 5.

The San Andreas Fault in California is an example of a(n)

transform plate boundary