Chapter 3: Matter, Energy, and Life Flashcards
Atom
the smallest particle of an element that retains all of the properties of that element; Democritus was a Greek philosopher that described the concept of an indivisible, invisible particle that made up all things; he
coined the term atom from the word atomos which means uncuttable.
What does John Dalton’s atom theory state?
- All elements are composed of atoms.
- Atoms of the same element are identical (and atoms of different elements are different).
- Atoms of different elements may combine to form compounds. (With whole number ratios)
- Even in chemical reactions, atoms do not change when separated from their original compounds.
What are the three basic types of subatomic particles?
- Protons (positively charges with mass of 1 amu)
- Neutrons (no charge with mass of 1 amu)
- Electrons (negatively charged with a mass of 1/1840 amu)
What did Ernest Rutherford do?
Received Nobel Prize in Chemistry in 1908 because he revolutionized J.J. Thomson’s Plum Pudding Model into a model with a separate nucleus and electron cloud. He identified the positive nucleus with his famous “gold foil”
experiment.
What does the atomic number represent?
The number of protons
What does the mass number represent?
The number of protons and neutrons added up
Isotope
an atom with a different number of neutrons than a regular atom of that element would
Coumpunds
two or more atoms chemically combined
Molecule
the smallest unit of a compound
What are the two types of chemical bonds?
- Ionic
- Covalent
Ionic Bonds
form when electrons are transferred or accepted between atoms.
Covalent Bonds
form when atoms share electrons; these bonds are stronger than ionic.
Ions
an atom with a different number of electrons than a normal atom of that element would have; this makes the atom postive or negative
What are the two types of ions?
- Cation
- Anion
Cation
positive ion (when an election is lost)
Anion
negative ion (when an election is gained)
pH
The pH scale indicates the acid/base qualities
of a substance; pH is logarithmic so each number on the scale is 10 times greater than the number before.
Acid
substance that gives up hydrogen ions
(H+) in solution. pH range is 1-6
Base
substance that gives up hydroxide ions
(OH-) in solution. pH range is 8-14
Organic Compounds
The molecules of life:
- Lipids – commonly called “fats”, include oils and waxes.
- Carbohydrates – hydrated carbon atoms
- Proteins – built by amino acids, enzymes are specialized proteins.
- Nucleic Acids – types include RNA and DNA
Energy
the ability to do work
Kinetic Energy
the energy of motion
Potential Energy
the energy of postion or storage
How is energy measured?
Energy can be measured by joules, calories, or other
*1 calorie = 4.184 joules
Heat
Heat is a form of energy that can be transferred between objects; If heat increases, molecular motion increases. Heat may cause objects to change
state (solid to liquid). Heat may be transferred by
conduction, convection or radiation.
Conduction
energy transferred by direct contact
Convection
enery transferred by mass motion of molecules
Radiation
energy transferred though electromagnetic radiation
The First Law of Thermodynamics
energy is not created or destroyed but conserved.
The Second Law of Thermodynamics
with repeated transfers, the “quality” of energy is lost leading to disorder or entropy.
Extremeophiles
live in severe conditions
Chemosynthesis
the process in which inorganic chemicals provide energy to create organic molecules.
Photosythesis
the process in which organisms convert light energy, normally from the Sun, into chemical energy
Light Dependant Reactions
Produce glucose molecules
Dark Reactions
Enzymes split water molecules releasing O2 and creates ATP and NADPH
Species
orgainisms of the same kind
Population
Species living in a given area at the same time.
Biological Community
all populations interacting in an area
Abiotic Factors
nonliving components such as temperature,
pressure, water, sunlight, etc.
Biotic Factors
living components such as secretions, wastes and remains.
Food Chains
A linked feeding series.
Food Webs
Interconnected food chains.
Producers
photosynthesizers that are the base of the food chain. This is primary productivity.
Secondary Productivity
manufacture of biomass by plant-eaters
Biomass
a biological material produced in a given area in a
given time period.
Trophic Levels
feeding levels
Example: Producer, then primary consumer, then secondary consumer, then tertiaty consumer
*only 10% of the energy gets passed on from one trophic level to the next
Name five cycles that take place in our environment.
- Hydrologic
- Carbon
- Nitrogen
- Phosphorus
- Sulfur
Hydrologic Cycle
“the water cycle”
the cycle of processes by which water circulates between the earth’s oceans, atmosphere, and land
The Carbon Cycle
the series of processes by which carbon compounds are interconverted in the environment, chiefly involving the incorporation of carbon dioxide into living tissue by photosynthesis and its return to the atmosphere through respiration, the decay of dead organisms, and the burning of fossil fuels
The NItrogen Cycle
the series of processes by which nitrogen and its compounds are interconverted in the environment and in living organisms, including nitrogen fixation and decomposition.
The Phosphorus Cycle
Compounds are leached from rocks and minerals over a
long period of time.
*Can lead to eutrophication
The Sulfur Cycle
Comes from rocks, soil and water. Taken in by organisms.
Fossil fuel exhaust increases levels.
*May cause acid rain.
Around hot water vents deep in the ocean live specialized communities. Bacteria turn H2S into reduced carbon compounds through chemosynthesis. The bacteria then provide food to other life forms. Comared to terrestrial food chains, the bacteria fill the same role as:
autotrophic, primary producers
On land, water that reaches the atmosphere from the surface of leaves does so through a process known as:
transpiration
Name a wave that is not a form of electromagnetic radiation.
sound waves
The atomic number of nitrogen is 7. A neutral nitrogen-15 atom is composed how many of each of the main subatomic particles.
7 protons, 8 neutrons, 7 electrons
Excessive inputs of nitrogen and phosphorus compunds may cause excessive growth of vegetation in surface waters. This process is known as:
eutrophication
Name a plant where nitrogen fixation will take place.
soy beans
A 3000 watt space heater wasa used for 3 hours. How much energy did the heater use?
9 kWh
Name an example of something that is not an ecosystem service.
ozone depletion
Nitrogen fixing bacteria can “fix” nitrogen by combining it with hydrogen to make ammonia (NH3). A plant crop especially useful to farmers have these bacteria living in their plant tissues and as a result enrich soil with nitrogen. These plants are:
legumes
Name an example of something that could decrease the amount of carbon dioxide in the atmosphere.
photosynthesis
Acid Rain with a pH of 5 is more acidic than distilled water by a factor of:
Since distilled water is rated a 7, and each number 10 times greater than the one before, acid rain is 100 times more acidic than distilled water.
Name an organism that could be a tertiary consumer.
Shark
As a general rule of thumb, only about ___% of the energy in one consumer level is represented in the next higher level.
10
Name a type of group of animals that do not remove waste from the environment when feeding.
Carnivores
Name two high-energy molecules.
ATP and NADPH
Entropy, the tendency toward disorder in a system resulting in less available energy to do work is part of which law of thermodynamics?
The second law of thermodynamics
One calorie is equal to how many joules?
4.184 joules
Extremophiles obtain energy for metabolic processes through:
chemosynthesis
The smallest unit of a compound is a ____ while the smallest unit of an element is an ____.
molecule and atom
Coumpounds such as H2O, CO2, CH4, SO2, N2, and O2 are held together by what type of bonds?
Covalent bonds
Organic compounds contain the element:
carbon
Bases are substances that give up what types of ions in water?
hydroxide
The dependant variable is usually plotted of the __-axis of a graph.
y
A special class of proteins that include catalysts are:
enzymes
The element cycle that contributes greatly to soil pH changes, acid rain, air pollution from burning fossil fuels, and human eye and respiratory illnesses is the:
sulfer cycle
