CHAPTER TWO Chemical Level of Organization Flashcards
what is chemistry?
study of the structure of matter
what is matter?
anything that takes up space and has mass
what is mass?
the amount of material in matter
solid?
fixed volume and fixed shape in ordinary temperatures and pressures. Solids possess particles that are held tightly together and are typically the densest of the three states.
liquid?
maintain a constant volume but have no fixed shape. Instead, their shape is determined by the shape of its container. The particles of liquids are loosely held together and are typically less dense than solids. Examples: water, soda, alcohol.
gases?
do not maintain a constant volume or fixed shape. Gases can be compressed or expanded; unlike liquids they will fill a container of any size. The particles of a gas independent of each other and therefore result in the least dense state. Example: air in our atmosphere.
Matter is composed of one or more types of substances called __?
elements
how many natural occuring elements?
92
approximately 96% of human body weight is created by only what four of them: _____
Oxygen (65%), Carbon (18.6%), Hydrogen (9.7%), and Nitrogen (3.2%).
11 principle elements that are most abundant in the human body?
CHON Oxygen, carbon, hydrogen, and nitrogen are among the 11 principle elements that are most abundant in the human body. Others include: calcium, phosphorus, potassium, iron, sodium, chlorine, etc.
The human body also contains 14 other elements in very small amounts which are?
These are known as the trace elements such as copper, zinc, manganese, and fluorine.
what is atom?
are the smallest indivisible unit of an element and are therefore the smallest stable units of matter
what to know about atoms?
- Everything around us is composed of atoms in varying combinations.
- Atoms are composed of subatomic particles,
what are the subatomic particles?
protons,nuetrons, and electrons
nucleus?
The nucleus contains one or more protons and it may contain neutrons as well.
how is atom’s mass determined?
The mass of the atom is primarily determined by the number of protons and neutrons in the nucleus.
what is electron cloud?
electrons of the atoms whirl rapidly around the nucleus
what is electron shell?
Electrons are often shown in a fixed orbit around the nucleus
element?
a pure substance consisting only of one type of atom
chemical symbol?
an abbreviation; Most of the symbols reflect the English names of the element but others reflect their names in other languages
atomic number?
of an atom defines the number of protons in the atom. Hydrogen (H) is the simplest atom, with an atomic number of 1. Thus an atom of hydrogen contains one proton
neutral atoms?
possess the same number of protons and electrons. A neutral atom of Hydrogen possesses one proton and one electron.
ion?
atoms possessing a charge
cation?
electron donor; positively charged atoms created by the loss of one or more electrons Na+
anion?
electron acceptor; negatively charged atoms created by the gaining of one or more electrons Cl-
mass number?
total number of protons and neutrons
All atoms of the same element possess a constant number of ___.
protons
isotopes?
atoms whose nuclei contain the same number of protons(same identically chemical properties), but different numbers of neutrons.
atomic mass?
The actual mass of an atom is known as its atomic weight, expressed as dalton. the atomic weight of an element is an average mass number that reflects the proportion of different isotopes; mass of protons (fixed) +mass of nuetrons (varies)
chemical bonds?
are INTERACTIONS that STABILIZE the outer energy levels of atoms.
reactive?
outer shell not full
inert?
outer shell is full
ionic bonds?
chemical bonds created by the TRANSFER of electrons from one atom to another atom
ionic bonds create what kind of charges?
transfer of electrons creates two ionized atoms: one a cation and the other an anion.
Ionic bonds are common in the formation of inorganic compounds such as ___.
acids, bases, and salts.
covalent bonds?
chemical bonds that form between neutral atoms rather than ionized atoms; Covalent bonds SHARE their electrons with each atom.
Covalent bonds are usually associated with ___?
organic compounds such as starch, proteins, lipids, etc.
single covalent bonds exist when__pair of electrons are shared
one
double covalent bonds exist when __ pair of electrons are shared between __ atoms.
two,two
polar covalent bonds?
UNEQUAL sharing of electrons due to the electronegativity of the atoms
nonpolar covalent bonds?
are those where the atoms share the electrons EQUALLY An example would be an oil or fat.
molecules?
made up of two or more atoms chemically joined together
compounds?
are chemical substances made up of atoms from two or more different elements, regardless of the type of bonds joining them together
Cells remain alive and functional by ____chemical reactions
controlling
These changes occur as atoms in the reacting substances, called ____, are rearranged to form different substances, called ___.
reactants, products
metabolism?
All of the reactions under way in the cells and tissues of the body at a given moment b. All of the reactions under way in the cells and tissues of the body at a given moment constitutes its metabolism.
work?
is the movement of an object or change in the physical structure of matter
Energy?
is the capacity to perform work.
Energy has no ___and does not ___ ___ ___. It can only be measured by its effects on ___.
mass, does not take up space, matter
potential energy?
stored energy
kinetic energy?
energy of movement
chemical notation rules?
a. The symbol of an element indicates one atom of that element.
b. A number preceding the symbol of an element indicates more than one atom of that element.
c. A subscript following the symbol of an element indicates a molecule with that number of atoms of that element.
d. Substances to the left of the arrow indicate the reactants in the chemical reaction while substances to the right of the arrow indicate the products from the reaction. The arrow indicates the direction of the reaction and reads as “yields”.
e. A superscript + or – sign following the symbol of an element indicates an ion.
decompostion reaction
(also called a catabolism) the chemical bonds of large molecules are broken down into less complex, smaller molecules.
a. Hydrolysis is a common decomposition reaction used to break down organic compounds.
b. ABC yields A + B + C or BOOKWORM = BOOK + WORM
sysnthesis reactions?
(also called an anabolism) smaller particles are bonded together to form larger, more complex molecules.
a.Dehydration synthesis is a common example of a reaction used to build complex organic molecules.
b. A + B + C yields ABC, or NOTE + BOOK = NOTEBOOK
exchange reactions?
parts of the reacting molecules are shuffled to produce new products that are neither smaller nor less complex.
a. AB + CD yields AC + BD or NOTEBOOK + WORM = NOTE + BOOKWORM
4. Chemical reactions can be reversible. A + B yields AB, then AB yields A + B.
5 factors effecting chemical reactions?
- Properties of the reactants
- Temperature
- pH
- Concentration and pressure
- Enzymes lower the activation energy requirements for chemical reactions.
Enzymes ___ the activation energy requirements for chemical reactions
lower
exergonic?
chemical reactions that release more energy that is required to run the reaction are said to be
endergonic?
chemical reactions that require more energy than is produced
Enzymatic reactions are _____ to processing ____, including all the molecules that can be synthesized or broken down by chemical reactions inside our bodies.
essential, metabolites
nutrients?
are essential metabolites that are normally obtained from the diet
organic nutrients?
possess carbon and hydrogen as the primary structural ingredient. Example: sugars, fats, proteins, etc.
inorganic nutrients?
lack carbon and hydrogen as the primary structural ingredient. Example: acids, bases, water, etc.
why is water so important?
compatible for life; unlike most substances, the densest state of water is as a liquid rather than as a solid.
polarity?
Remember water is held together by polar covalent bonds; Having an indicated pole (as the distinction between positive and negative electric charges).
How does water change other organic polar compounds?
the small positive charges on the water’s hydrogen atom can be attracted to the negative charges on another polar molecule, which changes the molecules’ shapes by pulling adjacent molecules together
cohesion and adhesion?
water molecules exhibit cohesion (they stick to each other) and adhesion (they stick to other polar molecules).
d. At the water surface, the hydrogen bonds between water molecules slow the rate of evaporation and create the phenomenon known as ___.
surface tension
surface tension?
surface tension acts as a barrier that keeps small objects from entering the water. For example, small objects such as dust particles are prevented from touching the surface of the eye by the surface tension produced by a layer of tears.
solubility for water?
The polar charges on water molecules gives water the ability to disrupt the bonds of a variety of compounds causing them to dissolve.
solution for water?
the individual particles become dispersed within the water, resulting in a solution=a HOMEOGEOUS MIXTURE of two or more substances.
solutes for water?
b. The medium in which other atoms, ions, or molecules are dispersed is called the solvent. In aqueous solutions, water is the universal solvent!
c. The dispersed particles are the solutes.
Lubrication for water?
Water is an effective lubricant because there is little friction between water molecules. Thus, even a thin layer of water between two opposing surfaces will greatly reduce friction between them. Example: synovial fluid of joints.
reactivity for water?
in our bodies, chemical reactions occur in water, and water molecules are also participating in some reactions, including hydrolysis and dehydration synthesis.
High heat capacity?
ability to absorb and retain heat.
High heat capacity for water?
a. Water has an unusually high heat capacity, because water molecules in the liquid state are attracted to one another through hydrogen bonding.
b. The temperature of water must be high before individual molecules have enough energy to break free to become a gas.
c. Water carries a great deal of heat away with it when it finally does change from a liquid to a gas. This feature accounts for the cooling effect of perspiration on the skin.
a large mass of water changes temperature very ___. This property is called ______
slowly; thermal inertia
why is water said to be polar? what happens when it is in a ionic compound solution ?
because it has a positive and negative pole due to the unequal sharing of electrons in its covalent bonds.
In solution, an ionic compound dissociates as water molecules break them apart. The anions are surrounded by the positive pole of the water molecule, and the cations are surrounded by the negative pole of the water molecule.
. The sheath of water molecules around an ion in solution is called a ___.
hydration sphere
hydrophilic?
Molecules that interact readily with water are called
hydrophobic?
Molecules that do not interact readily with water are called
electrolytes?
Soluble inorganic molecules whose ions will conduct an electrical current in solution
the _______ concentration in the body fluids is measured on the pH scale
hydrogen ions (H+)
acids?
acids are biological compounds that release hydrogen ions (H+) when placed in solution
____ acid is an important compound found in our stomachs and is necessary for the digestion of certain foods.
Hydrochloric acid (HCl)
Acids have a __ pH on the pH scale____. The more H+ ions released by the substance the more acid the substance is (closer to _).
low, (1 - 6.9)
Acids are proton ___
donors
base?
Bases are biological compounds that release hydroxide ions (OH-) when placed in solution also known as alkalinity.
Bases have a __ pH on the pH scale.
The more OH- ions released the more alkaline the substance is (closer to 14).
high, (7.1 - 14)
Bases are proton ___
acceptors
neutrals?
are biological compounds that release equal numbers of H+ and OH- when placed in solution. ii. H2O yields an equal number of H+ and an OH- in solution
salts?
are electrolytes that release cations other than H+ and anions other than OH-. NaCl, is a good example of a salt. Since salts do no release either H+ or OH- ions, it cannot be measured on the pH scale.
buffers?
are biological substances that resists rapid change in the pH by releasing hydrogen ions when their concentrations are too low (or by combining with them when the concentrations are too high).
The normal pH of blood is ___. Abnormal fluctuations in pH can result in illness, disease, and death.
7.35 to 7.45.
Acidosis occurs when pH drops below ____Alkalosis occurs when pH rises above ___
7.35. ,7.45.
organic molecules possess ___ and are formed from ___bonds.
carbon; covalent
there are four types of organic compounds
CHON Carbohydrates, lipids, proteins and nucleic acids.
Organic compounds are ____ made from ___ bonded ___.
polymers; covalently, monomers
dehydration synthesis for organic molecules?
Organic compounds are made by the removal of water molecules from between two monomers
hydrolysis for organic molecules?
- Organic compounds are BROKEN by the ADDITION of water between the monomers of a polymer
CARBOHYDRATES—the __ ___compounds of life. composed of __,___,__ in a ::_ratio.
most abundant, carbon, hydrogen, and oxygen in a 1:2:1 ratio.
Monosaccharides?
—one sugar unit—is the simplest carbohydrates.
Monosaccharides contain _-__ carbon atoms and are used to assemble ___carbohydrates; they are ___ of all carbohydrates
Monosaccharides contain 3-7 carbon atoms and are used to assemble LARGER carbohydrates such as disaccharides and polysaccharides (i.e. they are the MONOMER of all carbohydrates).
there are five possible monosaccharides? which ones are not used to construct carbohydrates? what are the isomers?
glucose, fructose, galactose, ribose, and deoxyribose; ribose and deoxyribose not used to construct carbohydrates. The first three monosaccharides are isomers. That is, they have the same chemical formula (C6H12O6) but they have a different structural arrangement.
Disaccharides?
—two sugar units—are the simplest short-chain carbohydrates.
There are three common disaccharides that you should be familiar with:
a. Lactose (glucose + galactose) is present in milk.
b. Sucrose (glucose + fructose) is a transport form of sugar used by plants and harvested by humans for use in food.
c. Maltose (two glucose units) is present in germinating seeds.
Polysaccharides?
are STRAIGHT OR BRANCHED chains of hundreds or thousands of sugar monomers.
Polysaccharides are also called ___ carbohydrates.
complex,
2 common Polysaccharides?
starch and glycogen
starch?
is a PLANT STORAGE form of energy, arranged as UNBRANCHED COILED CHAINS, easily hydrolyzed to glucose units.
glycogen?
is a HIGHLY BRANCHED CHAIN used by animals to STORE energy in muscles and liver.
LIPIDS ?
are greasy or oily compounds with little tendency to dissolve in water because they tend to be nonpolar (=hydrophobic).
All lipids are composed of and what not ratio?
are composed of CHO carbon, hydrogen and oxygen but not in a 1:2:1 ratio as carbohydrates.
Lipids are BROKEN down by _____ reactions and created by____ reactions.
Lipids are BROKEN down by HYDROLYSIS reactions and CREATED by DEHYDRATION SYSNTHESIS reactions
What are the variety of lipids?
fatty acids, glycerides, phospholipids, steroids, and eicosanoids
Fatty acids?
LONG CARBON CHAINS with HYDROGEN ATOMS attached
a. All fatty acids serve as ___ ___ and are absorbed from food or synthesized within body cells.
b. One end of the carbon chain, called the head, always bears a __ -___group.
c. The carbon chain attached to the head is called the ___ ____. It is hydrophobic, so fatty acids have limited solubility. The longer the tail, the___ the solubility.
a.energy sources
b. carboxylic acid group (-COOH).
c. hydrocarbon tail, lower
Saturated fatty acids?
have only single carbon-carbon bonds in their tail and tend to be solid at room temperature.
Unsaturated fatty acids are ___ at room temperature because one or more double bonds between the carbons in the fatty acids permit “kinks” in the tails.
liquids
how are Glycerides strung together?
one or more fatty acid chains attached to a glycerol
Individual fatty acids cannot be strung together in a chain by dehydration synthesis. But they can be attached to another compound, glycerol, through a similar reaction.
Different types of glycerides?
Glycerides are stored in fat deposits and must be broken down to___-___ and___ before they can be used as an energy source. Glycerides are also used for ___ and physical protection.
fatty acids and glycerol
insulation
Monoglycerides (one fatty acid attached to a glycerol), Diglycerides (two fatty acids attached to a glycerol), and Triglycerides (three fatty acids attached to a glycerol).
Phospholipids and glycolipids – formed by the attachment of two fatty acids plus a ___ group to a ___. Glycolipids are ___ with sugar groups attached to the head end. a. The long hydrocarbon tails of phospholipids and glycolipids are____, but the opposite ends, the non-lipid heads, are ___
b. In water, large numbers of these molecules tend to form droplets, or micelles.
c. Phospholipids are the main structural material of __ ___ where they arrange in bilayers.
phosphate group, glycerol.
phospholipids
hydrophobic; hydrophilic.
plasma membranes
Steroids?
possess a backbone of four carbon rings but no fatty acid tails.
a. They differ in the functional groups that are attached to the basic ring structure.
Cholesterol, an important steroid, is a component of plasma membranes in animal cells and can be modified to form sex hormones (testosterone and estrogen) and vitamin D.
eicosanoids?
are lipids derived from arachidonic acid, a fatty acid that must be absorbed in the diet because it cannot be synthesized in the body.
Leukotrienes
are produced by cells involved with coordinating the responses to injury or disease, and they will be considered in later chapters.
Prostaglandins
short chain fatty acids in which five of the carbon atoms are joined in a ring. These compounds are released by cells to coordinate or direct local cellular activities and they are extremely powerful, even in minute quantities.
PROTEINS are the most ___ of all biological compounds. They compose approximately 20% of total body weight. All proteins contain ____.
diverse; carbon, hydrogen, oxygen, and nitrogen. CHON
Proteins function in what 7 ways?
Proteins function as
1. structural material.
2. antibodies
3. transports agents
4. cell movements
5. hormones,
6. enzymes
7. storages agents
SMATCHES
monomer unit of a protein is an
what does it contain?
amino acid.
Amino acids are small organic molecules with a nitrogen group (amine) attached to a carboxyl group (acid) and an R group (remainder).
A polymer of amino acids is often called a ___
to reflect the special peptide bonds that form between the amino acids during dehydration synthesis.
polypeptide
Primary structure?
is defined as ordered sequences of amino acids each linked together by peptide bonds to form linear polypeptide chains.
i. There are ___ kinds of amino acids available in nature. Each differs only in what atoms are in the R position.
ii. The sequence of the __ amino acids is determined by __ and is __ for each kind of protein.
20,20,DNA,unique
Secondary structure?
alpha helix, beta-pleated sheets, or triple helix forms by hydrogen bonding between the atoms in the peptide bonds along the chain
Tertiary structure?
Folding due to interactions among R groups along the polypeptide chain
“supercoiling”
Quaternary structure?
Quaternary structure describes the twisting of two of more polypeptide chains.
i. Hemoglobin is an example of a typical globular protein.
ii. Keratin is an example of a typical fibrous protein.
Denaturation?
= changing the shape of a protein alters its function!! It is important to maintain homeostasis in the body in order to prevent denaturation of proteins.
Enzymes –
almost everything that happens in the body does so because an enzyme makes it possible
An enzyme is a biological catalyst and is almost always a protein. It speeds up the rate of a specific chemical reaction in the cell. The enzyme is not destroyed during the reaction and is used over and over
a. Enzymes are biological important____that act as catalysts which accelerate the rate of biochemical reaction by___ the amount of energy required to start the reaction (activation energy).
b. Enzymes possess an active site, a groove or pocket where substrates __and undergo a chemical reaction.
proteins, lowering, bind
. Substrate binding produces an ____-____ ___. Denaturation of the enzyme typically prevents the _____-____ ____from forming so the chemical reaction ___ ___.
enzyme-substrate complex.
shuts down
NUCLEIC ACIDS –
large organic compounds made of CHON + P (phosphorous).
The monomer unit of a nucleic acid is a __.
nucleotide
Each nucleotide consists of three components:
a. Five-carbon sugar (such as ribose or deoxyribose)
b. Nitrogen-containing base. There are two types of nitrogen bases: purines and pyrimidines:
i. There are two purines = either Adenine (A) and Guanine (G)
ii. There are three pyrimidines = either Cytosine (C), Thymine (T) found only in DNA, or Uracil (U) found only in RNA
c. Phosphate group.
Complimentary base pairing occurs between one ____ and one ___.
a. ____ always binds to Thymine (or uracil in the formation of RNA) with ___ hydrogen bonds
b. ____always binds to Guanine with __ hydrogen bonds.
purine and one pyrimidine.
adenine; two
guanine; three
The three most important nucleic acids are:
DNA, RNA, and ATP
Define DNA, RNA, and ATP?
DNA is a double-stranded helix carrying encoded hereditary instructions.
RNA is single-stranded and functions in translating the code to build proteins.
ATP is single nucleotide that contains three phosphate groups and can readily release the phosphates to release energy for the cell to perform work.
Differences between DNA and RNA:
Sugar group
DNA: deoxyribose sugar
RNA: ribose sugar.
Nitrogen bases
DNA: A, C, G, and T
RNA: A, C, G, and U.
Number of nucleotides
DNA: more than 45 million nucleotides while RNA: contains no more than 50,000 nucleotides.
Shape
DNA: anti parallel, a double-stranded helix
RNA: a single-stranded straight chain
Function
DNA: stores genetic information that controls protein synthesis
RNA: performs protein synthesis as directed by DNA.
