Ch. 2 A&P Flashcards
Definition of matter
Everything around us that has mass and occupies space
Definition of an element
Cannot be broken down into simpler substances
Definition of an atom
The smallest piece of an element and simplest unit of individual pieces of matter is an atom
Definition of a molecule
A molecule is a chemical structure composed of more than one atom
Definition of a compound
If a molecule contains atoms of more than one element, it is sometimes called a compound
Most important elements
Hydrogen- Atomic # 1
Oxygen-Atomic # 8
Nitrogen-Atomic # 7
Carbon-Atomic # 6
What is the structure of an atom?
Proton- Positive
Neutron
Electron- Negative
Protons=electrons
Atomic number
= Number of protons in an atom
All atoms of the same element have the same number of protons
What is atomic weight?
Average mass or weight of an atom
What is atomic weight?
Average mass or weight of an atom
What is an ion?
Atoms or molecules that have a + or - charge
What is an ionic bond?
In an ionic bond, anions and cations are held together by the attraction between positive and negative charges
Covalent Bond
Covalent bonds are very strong because the electrons tie the atoms together.
Hydrogen Bond
A hydrogen bond is the attraction between a positively charged hydrogen atom and a negatively charged atom in another molecule or at another site within the same molecule
What does metabolism refer to?
Metabolism refers to all of the chemical reactions in the body.
What is the definition of work?
Work is movement or a change in physical structure
What is the definition of energy?
Energy is the capacity to perform work
What is potential energy?
kinetic energy+heat
Stored energy
What is a decomposition reaction?
AB> A+B
What does catabolism refer to?
Catabolism refers to the breakdown of complex molecules within cells
What does particle size do?
Smaller particle size tends to speed up the rate of chemical reactions
What are catalysts and what do they do?
Catalysts (enzymes for example) increase the rate of chemical reactions without being used up in the reaction.
What does concentration do?
Increased reactant concentration results in increased rates of chemical reactions
