Chapter 2: Chemistry of Life Flashcards
Matter
anything that has mass and occupies space.
Element
a pure substance: cannot be broken down or decomposed into two or more substances.
Compound
A chemical combination of two or more elements.
How many elements are found in the body?
24
What are the major elements in the body?
Oxygen, Carbon, Hydrogen, Nitrogen, Calcium, Phosphorus
What are the lesser elements of the body?
Sulfur, Potassium, Sodium, Chlorine, Magnesium, Iron
What are the trace elements found in the body?
Chromium, Cobalt, Copper, Fluorine, Iodine, Manganese, Molybdenum, Selenium, Silicon, Tin, Vanadium, Zinc
Elements consist of what?
Atoms
What determines an elements atomic number?
The number of protons in the nucleus
What determines an elements atomic weight?
The number of protons and neutrons added together.
What are electrons?
tiny particles with a negative charge
Where do you find electrons?
Whirling around the nucleus on energy shells/rings
What are the maximum amount of electrons an energy ring can hold?
the energy ring closest to the nucleus can hold 2 electrons while the outer rings can hold 8 electrons.
Isotope
An atom containing a different amount of neutrons than protons.
Molecule
a particle composed of two or more atoms united by a chemical bond.
What is an ionic bond?
ionic bonds are formed when one atom transfers an electron from its outer shell to another atom.
Cation
Atoms with a positive charge
Anion
Atoms with a negative charge
Ionization
when dissolved in water, ionic bonds tend to break, or dissociate, creating a solution of positively and negatively charged ions that’s capable of conducting electricity.
Electrolytes
compounds that ionize in water and create a solution capable of conducting electricity.
Electrolytes are crucial for what?
the heart, nerve, and muscle function; the distribution of water in the body; and the occurrence of chemical reactions.
Ions
electrically charged atoms
What is a covalent bond?
covalent bonds are formed when two atoms share one or more pairs of electrons to try to fill their outer energy shells.
What is a hydrogen bond?
a hydrogen bond is a weak attraction between a slightly positive hydrogen atom molecule and a slightly negative oxygen or nitrogen atom in another.
Energy
the ability to do work
Potential energy
the potential to do work
Kinetic energy
energy in motion
Metabolism
the sum of all chemical reactions in the body
What are the two types of metabolic activity?
Catabolism and Anabolism
Catabolism
involves breaking down complex compounds into simpler ones, releases energy
Anabolism
Involves building larger and more complex chemical molecules from smaller subunits, requires energy input
What is a chemical reaction?
the formation or breaking of chemical bonds
Synthesis reaction
two or more substances combine to form a different more complex substance (A+B—> AB) energy is required
Decomposition reaction
A complex substance breaks down into two or more simpler substances, energy is released (AB–> A+B)
Exchange reaction
two molecules exchange atoms or groups of atoms, which form two new compounds (AB+CD—> AC+BD)
What are the inorganic molecules essential to human life?
water, oxygen, carbon dioxide, acids, and bases
Mixture
results when two or more substances blend together rather than chemically combine. each substance retains its own chemical properties, and can e separated.
What are the types of mixtures?
solution, colloid, and suspension
Solution
consists of particles of matter called the solute, dissolved in a more abundant substance called the solvent. can be a gas, solid, or liquid at room temperature. Solvent must be clear, particles cannot separate out of the solvent when the solution is allowed to stand.
Colloid
Can change from liquid to gel
particles small enough to stay mixed (large enough to make mixture cloudy)
Suspension
Contains large particles, making it cloudy or opaque
if allowed to stand the particles will separate and settle at the bottom or the container
What is an Acid?
any substance that releases H+ when dissolved in water (also called proton donors)
What is a Base?
alkaline compounds also called proton acceptors
