Anatomy Chapter 2
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Anatomy Chapter 2
Atoms are the baic particles of ______
What are the smallest units of matter?
Protons and neutrons reside in the ____ of an atom
What is Atomic Number?
THe number of protons in an atom
Each ______ includes all the atoms that have the same number of protons and thus the same _____________
Within an atom, an ______________ surrounds the nucleus
What is the mass number of an atom?
the total number of protons and neutrons in its nucleus
What are Isotopes?
atoms of the same element whose nuclei contain different numbers of neutrons
Electrons occupy an orderly series of _________, commonly illustrated as ___________
The _______ in the outermost energy level determine an element's chemical properties
Atoms can combine through chemical reactions that create _________
What is a molecule?
Any chemical structure consisting of atoms held together by covalent bonds
What is a compound?
a chemical substance made up of atoms of two or more elements
What is an ion?
atoms that have gained or lost electrons
An __________ results from the attraction between ions
What are Cations?
positively charged ions
What are Anions?
Negatively charged ions
Atoms that share electrons to form a molecule are held together by ________
A sharing of one pair of elections is a __________
single covalent bond
A bond with unequal sharing of electrons is a
polar covalent bond
What is a hydrogen bond?
a weak but important, force that can affect the shapes and properties of molecules
What is the molecular weight of a molecule?
the sum of the atomic weights of its component atoms
THe rules of _________ are used to describe chemical compounds and reactions
Thre important chemical reactions in physiology
A chemical reaction occurs when _____ are rearranged to form one or more _______
What is metabolism?
THrough metabolism, cells capture, store, and use energy to maintain homeostasis and to perform essential functions
What is work?
The movement of an object or a change in the physical structure of matter
Cells gain energy to power their functions by
WHat is Catobolism?
thre breakdown of complex molecules
What is Anabolism?
The synthesis of new molecules
At equilibrium, the rates of two opposing reactions are
Enzymes catalyze specific biochemical reactions by
lowering a reactions activation energy
What is Activation Energy?
the amount of energy required to start a reaction
What is a catalyst?
compounds that accelerate chemical reactions without themselves being permanently changed or consumed
Inorganic compounds lack
Organic compounds contain
What are nutrients?
the essential elements and molecultes normally obtained from the diet
What are metabolites?
molecules that can be synthesized or broken down by chemical reactions inside our bodies
Nutriends and metabolites can be broadly categorized as either _______ or __________
inorganic or organic compounds
Physiologic systems depend on _____
Electrolytes are ________ compounds
Electrolytes undergo _______ in water to form ions
Molecules that interact readily with water molecules are called
Molecules that do not interact readily with water molecules are called
The pH of a solution idicates the....
concentration of hydrogen ions it contains
An acid releases
a base removes
What is the function of a buffer?
to remove or replace hydrogen ions in solution
Carbohydrates contain ______, ______, and ______ in a _________ ratio
carbon, hydrogen, and oxygen
Carbohydrates are most important as an ______ source for __________ processes
The three major types of carbohydrates
monosaccharides ( simple sugars)
Disaccharides and polysaccharides form from monosaccharides by
Lipids contain a carbon to hydrogen ratio of
The five important classes of lipids are
Triglycerides consist of three ______________ attached by __________ to a molecule of glycerol.
fatty acid molecules
3 facts about Steriods
1. Are components of plasma membranes
2. Include sex hormones and hormones regulation metabolic activities
3. Are important in lipid digestion
Structural lipids that are componenets of micelles and plasma membranes
phospholipids and glcolipids
Protiens are formed from ____________ and contain __________________________________
carbon, hydrogen, oxygen, and nitrogen
Seven important types of proteins are
Proteins are chains of
What is a polypeptide?
a linear sequence of amino acids held together by peptide bonds
THe four levels of protein structure
primary structure ( amino adic sequence(
secondary structure ( amino acid interactions, such as hydrogen bonds)
Tertiary structure ( complex folding, disulfide bonds ,and interaction with water molecules(
Quaternary structure ( formation of protein complexes from individual subunits
Fibrous protiens are
enlongated, tough, durable, and generally insoluble
Globular proteins are
generally rounded and water soluble
the reactants in an enzymatic reaction are called
What are Cofactors?
ions or molecules that must bind to the enzyme before substrate binding can occur
What are Coenzymes
orgainc cofactors commonly derived from vitamins
THe shape of a protein determines its ____________
DNA and RNA are
What are Nucleic acids?
they store and process info at the molecular level
DNA stands for
RNA stands for
What are nucleic acids?
Each nucleotide contains a ____, a ______, and a __________
DNA contains the nitrogenous bases
RNA cones the nitrogenous bases
What is ATP?
a high-energy compound used by cells
THe most important high-energy compound is
Cells make ATP by
adding a phosphate group to ADP through phosphorylation
Chemicals from functional units called
What is Metabolic turnover
the continuous removal and replacement of cellular organic molecules
Metabolic turnover allows cells to
change and to adapt to changes in their environment