Exam Two: Part Two Flashcards
what are ATOMS?
- the SMALLEST COMPONENT of a substance–retains the PROPERTIES of the SUBSTANCE
- contains the NUCLEUS (its center)
- protons (+)
- neutrons ( )
(same number of protons and neutrons) - contains ELECTRONS move around the nucleus in ElECTRON SHELLS (-)
what are ELEMENTS?
ELEMENTS:
- made of the same KIND OF ATOMS
- have around 98 natural elements
- all are found on the PERIODIC TABLE OF ELEMENTS
describe ELECTRON CONFIGURATION.
ELECTRON CONFIGURATION:
- arrangement of ELECTRON SHELLS around the NUCLEUS
- These shells can only hold a certain amount of electrons
(2e, 8e, 8e)
- the ABILITY of an ATOM to COMBINE WITH OTHER ATOMS–all depends on # of electrons on those outer shells
- lots of sharing–because the ELEMENT wants to COMPLETE its OUTER ELECTRON SHELL CAPACITY
*want to be like the noble-gases
what are MOLECULES?
MOLECULES:
larger structures organized that are made up of ATOMS
- often made from a COMBINATION of CHNOPS (the MACRONUTRIENTS)
(carbon, hydrogen, nitrogen, oxygen, phosphorus, and sulfur)
what are CHEMICAL BONDS?
CHEMICAL BONDS:
- a force that holds TWO ATOMS TOGETHER
- formed to try to STABILIZE an ATOM’S OUTERMOST ELECTRONS
- ENERGETICALLY FAVORABLE
THREE TYPES:
- IONIC
- COVALENT
- HYDROGEN
describe IONIC BONDS
IONIC BONDS:
a type of chemical bond that has formed as a RESULT of the COMPLETE TRANSFER OF VALENCE ELECTRONS FROM ONE ATOM TO ANOTHER
**recall about IONS–ATOMS are ELECTRICALLY NEUTRAL
**loss or gain of an electron creates CHARGED ATOMS = IONS
(CATIONS + ANIONS)
describe COVALENT BONDS
COVALENT BONDS:
- a chemical bond that involves the SHARING OF ELECTRON PAIRS BETWEEN ATOMS
- much more common in ORGANISMS
- STRONG and DO NOT DISSOCIATE IN WATER
describe HYDROGEN BONDS
HYDROGEN BONDS:
- WEAK type of force
- a HYDROGEN ATOM bonds to a STRONGELY ELECTRONEGATIVE ATOM within its VICINITY OF ANOTHER ELECTRONEGATIVE ATOM
- WEAKER BONDS vs. covalent and ionic
- it is INTERMOLECULAR (BETWEEN
MOLECULES) vs. INTRAMOLECULAR (INSIDE MOLECULES)
what is a CHEMICAL REACTION?
CHEMICAL REACTION:
- when CHEMICAL BONDS are FORMED or BROKEN BETWEEN ATOMS
- always has a CHANGE OF ENERGY
- absorbs more than it releases – vice versa
THREE TYPES:
- SYNTHETIC
(living organisms –anabolism)
- DECOMPOSITION
(living organisms–catabolism)
- EXCHANGE
what are INORGANIC COMPOUNDS/MOLECULES?
- molecules that LACK CARBON
- seen in WATER, OXYGEN, CO2, ACIDS, BASES, and SALTS
- 1-1.5% of living cells
describe WATER
- has a lot of STRUCTURAL AND CHEMICAL PROPERTIES that make it special
POLAR MOLECULE:
- has an UNEVEN DISTRIBUTION of charges between OXYGEN (-) AND HYDROGEN (+)
*electrons are pulled to the oxygen
describe POLARITY and its 4 IMPORTANT CHARACTERISTICS
- the FORMATION OF 4 HYDROGEN BONDS with nearby WATER MOLECULE–makes water an EXCELLENT TEMPERATURE BUFFER
- ICE (LESS DENSE that water)
- has more stable hydrogen bonds - makes it an EXCELLENT SOLVENT
- many polar substances dissolve in water - big support in WATER’s ROLE in CHEMICAL REACTIONS
- split/rejoins H and OH
- very common REACTANT/PRODUCT
definition of ACIDS
compound that releases H when mixed with WATER
definition of BASES
compound that releases OH when mixed with WATER
definition of SALTS
substance that DISSOCIATES in water into CATIONS and ANIONS
- do not release H or OH into the solution
- they are the PRODUCT of the MIXTURE OF AN ACID AND BASE
definition of pH
pH:
the CALCULATION OF THE CONCENTRATION OF H in a SOLUTION
- represents acidic or basic solution is
- range between 1-14 (acidic-basic)
**NEARLY all biological systems function at pH 7
definition of BUFFERS
- we always need to have a balance of ACIDS and BASES as they always change as well as our pH
BUFFERS:
chemicals or mixtures of chemicals that keep pH from CHANGING in EXPERIMENTS or BIOLOGICAL SYSTEMS
- have certain MIN or MAX pH growths for various microorganisms
what are ORGANIC COMPOUNDS/MOLECULES?
- always have CARBON AND HYDROGEN
- has a VARIETY OF ATOMS - can form straight or branched (carbon has 4 electrons)
- capable of more COMPLEX BIOLOGICAL FUNCTIONS
- forms BASIS OF LIVING CELLS
what are some common STRUCTURES seen in ORGANIC COMPOUNDS?
- straight chains
- branched chains
- rings
composed of a CARBON SKELETON
what are some COMMON ELEMENTS seen in ORGANIC COMPOUNDS?
CHNOPS
- carbon, hydrogen, sulfur, phosphorous, and nitrogen
what are FUNCTIONAL GROUPS?
responsible for the CHARACTERISTIC REACTIONS of that PARTICULAR COMPOUND
- do not exist on their own
- can be many in one; ex. AMINO ACIDS with an amino and carboxyl group
- help with CLASSIFICATION of organic compounds
what are the COMMON FUNCTIONAL GROUPS found in BIOMOLECULES?
- LIPIDS AND PROTEINS: carboxyl
- PROTEINS: amino
- LIPIDS AND CARBS: hydroxyl
- ATP/DNA: phosphate
what are MACROMOLECULES?
- small organic molecules that combine to make very large molecules
- often made from POLYMERS–formed by COVALENT BONDING due to MONOMERS
TYPES:
- LIPIDS
- PROTEINS
- NUCLEIC ACIDS
- CARBS
dehydration synthesis and hydrolysis
- processes that makeup MACROMOLECULES
DEHYDRATION SYNTHESIS:
glucose and fructose – sucrose
HYDROLYSIS
maltose + addition of water = glucose
describe CARBOHYDRATES
- GENERAL FORMULA: (CH2O)n
- made up of MONOMERS;
simple sugars; mono/disaccharides
POLYSACCHARIDES
- polymer of MONOSACCHARIDES
- COMPLEX CARBS
(ex. starch and cellulose)
FUNCTION:
- ENERGY STORAGE
(starch - plants)
(glycogen - animals)
- STRUCTURE
- cellulose in plants
- NUCLEIC ACIDS
describe LIPIDS
molecule of FAT is formed when a molecule of GLYCEROL combines with 1-3 FATTY ACID MOLECULES
- contains a CARBOXYLIC ACID AND FUNCTIONAL GROUP
STEROIDS:
- LIPIDS with interlocking rings
- important for the PLASMA MEMBRANES OF ANIMAL CELLS
- prevents PACKING of FATTY ACID CHAINS and HARDENING
FUNCTION:
- INSULATION
- ENERGY STORAGE
- MEMBRANES
- created by specific PHOSPHOLIPIDS
- cell bilayer with hydrophobic/philic bonds
describe PROTEINS
complex molecules that perform a VAST ARRAY of functions within organisms
- enzymes
- DNA replication
- transport
- responding to stimuli
- structures
made up of AMINO ACIDS (20)
- short c-skeleton
- amino group
- carboxylic acid group
- r-group
a chain of these are called; POLYPEPTIDES
- has structures; PRIMARY, SECONDARY, and TERTIARY
(3D STRUCTURE - responsible for its FUNCTION; without it or thrgh, DENATURATION –hard to refold)
describe NUCLEIC ACIDS
large BIOPOLYMERS ESSENTIAL to life
- made from NUCLEOTIDE MONOMERS
- 5-carbon sugar
- phosphate group
- nitrogenous base
(thymine-cytosine guanine-adenine DNA
RNA thymine–uracil)
describe DNA
- the genetic instruction for all LIFE
- FOUR BASES: backbone that encodes information
- formation of DOUBLE HELIX
describe RNA
- SINGLE-STRANDED
- has RIBOSE vs. DEOXYRIBOSE
- converts into mRNA, tRNA, and rRNA
