lack carbon or C-C or C-H bonds
have at least one carbon atom and atleast one C-C or C-H bond. Form covalen bonds, hydrophobic (non polar)
molecules composed of carbon, hydrogen, and oxygen atoms. Function: energy storage, provide skeleton for building other organic molecules. Three main classes.
simple sugars, 3-7 C atoms. eg. glucose, fructose, galactose
two simple sugars chemically combined
dehydration synthesis reactions
connect molecules by extracting water
sepatation of subunits by the addition of a water molecule
many monosaccharides chemically joined together. eg. starch, glycogen. Large, insoluble, used to store energy.
water-insoluble organic molecules made mostly of carbon and hydrogen atoms.
must abundant lipids and most concentrated source of energy. Building blocks = one glycerol and three fatty acids.
linoleic and linolenic
essential fatty acids
saturated fatty acid
all avilable bonds are filled (single bonds)
unsaturated fatty acid
has one or more double bonds
a modified simple sugar (sugar alcohol)
has a long chain of carbons that are bonded to hydrogen atoms and at one end is a carboxylic acid group
unsaturdated fats that have been solidified by adding hydrogen atoms at the double bonds (converting unsaturated fat into a saturated fat or partially saturated).
Omega 3 fatty acids
include EPA, DHA (cold water fish), and alpha linolenic acid (dark green leafy vegetables, nuts, beans, and flaxseeds).
Omega 6 fatty acids
include linoleic acid, come from plants (peanuts, sunflowers, whhole grain, primrose oil).
fat compounds where one fatty acid has been replaced by a phosphate group. Has a hydrophilic head and hydrophobic tail. Can assemble into bilayers (make up cell membranes).
the most common phospholipids
1. phosphatidylcholine 2. phospatidylethanolamine 3. phosphatidylerine 4. phosphatidylinositol
hormone-like compounds formed from the phospolipids in cell membranes that act locally in clotting, inflammation, and immune defense.
flat molecules made of four interlocking hydrocarbon rings. Fat soluble and contain little oxygen.
a steroid that comes from animal products, and some is also produced by the liver. Essential for the production of hormone Vitamin D and bile salts. Excess intake can lead to fatty deposits in the walls of blood vessels.
fatty deposits in the walls of blood vessels due to excess intake of cholesterol
an example of an eicosanoid (tissue hormone)
most abundant organic compounds of the human body, composed of subunits called amino acids.
functions of proteins
support and structural proteins (cytoskeleton), movement (muscle), transport (channels, carriers), defense (antibodies, nails, hair), metabolic regulation (hormones, enzymes)
consist of a carbon atom, an amino group, a carboxyl group, a hydrogen atom, and a side chain. 8 essentials (can't be produced by the human body), 12 nonessentials (can be produced by human body).
a bond that forms when a dehydration synthesis reaction occurs between the amino group of one amino acid and the carboxylic acid group of another.
a molecule composed of two amino acids linked by a peptide bond
a molecule composed of three covalently linked amino acids
a molecule with 10 or more covalently linked amino acids. take on complex conformations that are essential to their function.
structural levels of proteins
primary, secondary, tertiary, quaternary
primary protein structure
linear sequence of amino acids that make up the polypeptide chain
secondary protein structure
polypeptide is coiled or bent into pleated sheets stabilized by hydrogen bonds
tertiary protein structure
secondary structure can be further twisted, resulting in a globular shape that is held together by nteractions of the R-groups (ionic or hydrophobic interactions, hydrogen bonds, disulfide bridges)
interaction between two or more polypeptide chains
strandlike and tend to pack together in ropelike structures. Tend to be insoluble in water and are very stable, so they are ideal for support. eg. keratin, collagen, and elastin.
spherical compact structures that tend to be water soluble and chemically reactive. eg. immunoglobulins, hormones, and enzymes.
based on the amino acid sequence, is the basis for function.
have lost their shape and therefore their function. This can happen by changes in pH, temperature, radiation, and other chemicals. If the chemical environment is restored, confomation may be reformed and function returned.
composed of deoxyribonucleotides. Pentose sugar (deoxyribose), phosphate group, nitrogenous base (cytosine, thymine, guanine, or adenine)
cytosine, thymine (DNA only) , uracil (RNA only)
alternating deoxyribose sugar and phosphate unites form backbone of the polynucleotide chain. Two polynucleotide chains join by hydrogen bonds to form the double helix. Complementary base pairing between chains (G to C, A to T)
the molecule of heredity, contorls the function of the cell by controlling protein synthesis. Base pairing is key
specific sequences of nucleotides along a chromosome. unit of inheritance that determines a specific characteristic
the 2 strands of the double helix unwind, the hydrogen bond between the base pairs breaks apart. DNA polymerase attaches complementary nucleotides to the exposed bases on each of the polynucleotide chains. At the end, there are two chromosomes and each is composed of one polynucleotide chain from the original chromosome and a complementary chain that was formed by base pairing.
synthesize a molecule of RNA by using a gene (DNA sequence) as a template. The enzyme RNA polymerade breaks apart the hydrogen bonds holding the double helix of DNA together and starts to make a complementary copy of one of the polynucleotide chains. the complementary copy is composed of RNA molecules. the same base pair rule is used but uracil is used instead of thymine.
using the genetic message copied in the RNA molecule to make a protein
RNA (ribonucleic acid)
composed of the pentose sugar ribose, phosphate group, and a nitrogenous base. some molecules are temporary copies of segments (genes) of the DNA and are involved in synthesizing proteins. some molecules are regulatory, acting as enzymes (ribozymes) or silencing gene expression (RNA interference).
ATP (adenosine triphosphate)
composed of ribose, adenine, and three phosphate subunits. High energy bonds are present between phosphate groups, chemically unstable because of the close proximity of 3 highly charged phosphate groups. Cleavage of high energy bonds releases energy during reactions. energy stored is used to do the body's cellular work. Split into ADP and an inorganic phosphate group.
cAMP (cyclic AMP)
made from ATP by removing two phosphate groups to form a monophosphate, used as an intracellular signal
NAD and FAD
used as coenzymes to transfer energy-carrying electrons from one chemical pathway to another.
combining of two or more substances to form a more complex substance, formation of new chemical bonds
breaking down of a substance into two or more simpler substances, breaking of chemical bonds
decomposition of two substances and synthesis of two new compounds from them by rearrangement of chemical bonds between atoms.
all of the chemical reactions that occur in body cells
chemical reactions that join simple molecules together to form more complex molecules, the chemical reaction responsible is dehydration synthesis
chemical reactions that break down complex compounds into simpler ones and release energy, hydrolysis is a common one. the end products are carbon dioxide, water, and other waste products. more than half the energy released is transferred to ATP, which is then used to do cellular work.