Glossary of Biology 111-Week 4: Energy and Matter

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What is matter?
It is defined as anything that has mass and occupies space, such as a solid, liquid, or gas.
What is energy?
It is defined as the ability to do work.
What are the two types of energy?
potential (stored) and kinetic (motion)
What forms can kinetic energy take?
radiant (light), sound (hearing), chemical (ATP), electric (+ or - charge), mechancial (the energy of movement)
Energy and matter...
Life fluctuates between these.
What are the subatomic particles?
protons (+), neutrons (no charge), and electrons (-)
What is an atom?
It is defined as the smallest uint of matter that retains properties of an element.
What is an element?
It is defined as any substance that cannot be broken down into another substance through natural means.
What is an orbital of an atom?
the physical location of electrons 90% of the time
What is a shell of an atom?
an atom's energy level
What is a valence shell?
the highest energy level of electrons
How many electrons can the first shell hold?
How many electrons can a shell hold?
eight (excluding the first shell, which can only hold two)
How an atom behaves when it comes into contact with other atoms is determined by its _____.
electron configuration
Changing the number of _____ would change an atom into an atom of a different element.
protons (all elements of one type have the same number of protons)
What are isotopes?
elements that have a different number of neutrons (this changes the atomic weight, but not the atomic number-number of protons)
What is a radioactive isotope?
an isotope that spontaneously decays, giving off particles and energy (these can be detected by certain machines)
Are all elements natural?
no, some are man-made
What is an atomic number?
the number of protons (found on top of an element square)
What is atomic mass?
the weight of protons and neutrons together (electron weight is negligible)
How much does each proton or neutron weight?
one a.m.u (atomic mass unit or "dalton") a piece
What is one amu or dalton?
1.7 x 10 to the power of -24
What are chemical bonding patterns?
gaining or losing valence electrons to complete the valence shell
What is the relation of electrons to protons?
electrons are -charged, thus canceling the +charge of protons. When valence electrons are gained or taken, this can change the atom's charge to more + or -.
Elements on the left side of the periodic table...
have a spherical rotation called the x-axis and are electron donors
Elements on the right side of the periodic table...
have a dumbbell rotation called the y-axis, and are electronegative-electron takers
Elements in the middle of the periodic table...
have a 3-D rotation called the z-axis
What is a molecule?
It is defined as similar atoms atoms chemically bonded together
What is a compound?
It is defined as different atoms chemically bonded together (ie.H20)
When chemical bonds form, what happens to energy?
Energy is stored. (potential)
When chemical bonds break, what happens to the energy?
Energy is released (kinetic).
What is electronegativity?
the attraction of an atom for the electrons of a covalent bond, the degree of which causes some atoms to be slightly charged + or -
What is a non-polar covalent bond?
equal sharing of electrons between atoms, which causes the molecule/compound to be neutrally charged
What is a polar covalent bond?
unequal sharing of electrons, where the electronegativity of one atom is stronger causing the atoms to be slightly charged + or -
What is an ionic bond?
bond formed when atoms give/take valence electrons leaving a + or - charge, which causes the + and - charged atoms to become strongly attracted to each other (electrostatic attraction)
What is electrostatic attraction?
strong interaction between charged ions
What is an ion?
a + or - charged atom:
cation= +charged ion
anion= -charged ion
What is a hydrogen bond?
a bond between hydrogen and an electronegative atom- the + and - attract for a weak, temporary bond
What are Van der Walls Interactions?
weak chemical bonds due to the localized charge fluctuations of electrons in constant motion; these can happen to any element and are easy to pull apart like sticky notes
What does a synthesis rxn(reaction) do?
atoms to molecules/compounds
What rxn builds bonds? What rxn stores energy?
anabolic rxn builds bonds (matter);
endergonic rxn stores energy (potential energy)
What rxn breaks bonds? What rxn releases energy?
catabolic rxn breaks bonds (matter);
exergonic rxn releases energy (kinetic energy)
What do decomposition rxns do?
molecules/compounds to atoms
What is metabolism?
It is ALL of an organism's chemical rxns.
What are coupled rxns?
rxns that use synthesis and decomposition, such as using endergonic rxns to drive exergonic rxns
What factors affect rxns?
*temperature (excites reactants, giving energy to enhance or stop)
*catalyst (enzymes- proteins coded from DNA- which lowers Energy of Activation)
*concentration of reactants and products (gives more of a chance to form rxns)
What is the goal that drives the regulation of rxns?
to maintain homeostasis- steady internal state
All biochemical pathways are regulated by what?
feedback mechanisms
What types of feedback are used and what do they do?
positive feedback enhances initial change in homeostasis
negative feedback counters initial change in homeostasis
Stimulus is needed to cease feedback
What is bioenergentics?
the study of how organisms manage their energy resources
What is thermodynamics?
the study of energy transformations that occur in a collection of matter
What are the laws of thermodynamics?
principle of conservation: energy can be transferred or transformed but not created or destroyed
2nd: every energy transfer or transformation increases entropy (measure of disorder)
What is free energy? What are the variables used for free energy formulas?
the portion of a system's energy that can perform work when temperature is uniform throughout a system
G= total energy
H= free energy
T= temperature
S= entropy
What are the characteristics of the states of matter?
*solid stores lots of energy, is highly bonded, maintains its shape
*liquid releases bits of energy as chemical bonds break, little bit more energetic, takes form of container
*gas has highly energetic molecules, decreased amount of bonding, expansive but pressurizes when contained-depending on concentration and inherent energy of molecules

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