2.3-2.4 Flashcards
energy (def)
capacity to do work
work (def)
to move something
energy classified into…
potential
kinetic
potential (def)
stored energy due to its position or internal state
kinetic (def)
energy of motion
energy that is doing work
chemical energy
chemical reactions
potential energy stored in bonds of molecules
chemical rxns release this energy and make it available for physiological work
heat is ___ energy (def)
kinetic energy of molecular motion
free energy (def)
in humans
potential energy available in a system to do useful work
energy stored in chem bonds of organic molecules
chemical reaction (def)
process in which a covalent or ionic bond is formed or broken
chemical rxn classifications:
decomposiiton
synthesis
exchange
decomposition rxns (what are they)
large molecule breaks down into multiple smaller ones
synthesis rxns (what are they)
multiple small molecules combine to form a large one
exchange rxns (what are they)
2 molecules exchange atoms or groups of atoms
law of mass action in reversible rxns
proceed from reactants in greater quantity to substances w/ lesser quantity
reversible reactions exist in a state of equilibrium
ratio of products to reactants is stable
ex. 20:1
chem rxn rates are based on…
molecular motion
collisions
rate of rxn depends on
nature of the reactants
frequency and force of their collisions
some factors that affect rxn rates
concentration
temp
catalysts
factors that affect rxn rates:
concentration (explain)
more concentrated == rxn rate increases
molecules are more crowded and a collide more frequently
factors that affect rxn rates:
temp (explain)
temp increases == rxn rate increases
heat causes molecules to move more rapidly and collide w/ greater force and frequency
factors that affect rxn rates:
catalysts (explain)
substances temporarily bind to reacts and hold them in favorable position to react w/ each other
may change shapes of reactants in ways to make them more likely to react
metabolism (def)
sum of all chem rxns in body
2 division of metabolism
catabolism
anabolism
catabolism (def)
energy-releasing decomposition rxns
break covalent bonds
break larger molecules down into smaller molecules
exergonic – releases energy to be used for other physiological work
exergonic (def)
energy-releasing rxns
physiological work (examples)
breaking chem bonds
building molecules
pumping blood
contracting skeletal muscles
anabolism (def)
energy-storing synthesis rxns
ex. production of protein or fat
endergonic – require an energy input
anabolism is ___ by the ___ that catabolism releases
driven
energy
anabolism and catabolism are…
coupled
inseparably linked
oxidation (def)
any chemical rxn in which a molecule gives up electrons and releases energy
molecule is oxidized when it loses electrons
oxidizing agent is the electron acceptor that takes the electrons
reduction (def)
chem rxn in which a molecule gains electrons and energy
molecule is reduced when it gains electrons
reducing agent is the electron donor that donates the electrons
redox rxns are always ___
coupled
oxidation of 1 molecule is always accompanied by the reduction of another
are only electrons transferred in a redox rxn?
no; often electrons are transferred in the form of hydrogen atoms
energy-transfer reactions in the human body:
exergonic reactions (def)
rxns in which there is a net release of energy
products have less total free energy than reactants
energy-transfer reactions in the human body:
endergonic reactions (def)
rxns in which there is a net input of energy
products have more total free energy than reactants
energy-transfer reactions in the human body:
exergonic rxns (examples)
oxidation
decomposition
catabolism
energy-transfer reactions in the human body:
endergonic rxns (examples)
reduction
synthesis
anabolism
energy-transfer reactions in the human body:
oxidation
exergonic
electrons removed from reactant
electrons can be removed in the form of hydrogen atoms
product is said to be oxidized
energy-transfer reactions in the human body:
decomposition
exergonic
rxn such as digestion and cell respiration
larger molecules are broken down into smaller ones
energy-transfer reactions in the human body:
catabolism
exergonic
sum of all decompositions rxns in the body
energy-transfer reactions in the human body:
reduction
endergonic
electrons are donated to a reactant
product is said to be reduced
energy-transfer reactions in the human body:
synthesis
endergonic
rxn such as protein or glycogen synthesis, in which 2 or more smaller molecules are combined into a larger one
energy-transfer reactions in the human body:
anabolism
endergonic
the sum of all synthesis rxns in the body
chemical energy (def)
potential energy stored in bonds of molecules
functional groups (what are they)
common arrangement of atoms that give organic molecules their unique properties
organic chemistry (def)
study of compounds of carbon
4 primary categories of large organic molecules
carbohydrates
lipids
proteins
nucleic acids
why is carbon important?
carbon is an especially ___ atom that serves as the basis of a wide variety of structures
versatile
why is carbon important?
carbon has ___ valence electrons, so it bonds w/ other atoms that can provide it w/ 4 more to complete its valence shell
4
why is carbon important?
carbon atoms readily ___ with each other and can form ___ chains, ___ molecules, and ___ – an enormous variety of ___ for organic molecules
long chains
branched molecules
rings
carbon backbones
why is carbon important?
carbon also commonly forms covalent bonds w/…
hydrogen
oxygen
nitrogen
sulfur
why is carbon important?
carbon backbones carry a variety of ___
functional groups
functional groups (def)
small clusters of atoms that determine many of the properties of an organic molecule
5 common functional groups
1) hydroxyl
2) methyl
3) carboxyl
4) amino
5) phosphate
hydroxyl (symbol and occurs in)
–OH
sugars, alcohols
methyl (symbol and occurs in)
–CH3
fats, oils, steroids, amino acids
carboxyl (symbol and occurs in)
–COOH
amino acids, sugars, proteins
amino (symbol and occurs in)
–NH2
amino acids, proteins
phosphate (symbol and occurs in)
–H2PO4
nucleic acids, ATP
most macromolecules are ___ –molecules made of repetitive series of identical or similar subunits called ___
polymers
monomers
polymers (def)
molecules made of a monomers
monomers (def)
a repetitive series of identical or similar subunits that made up polymers
polymerization (def)
joining of monomers to form a polymer
dehydration synthesis (condensation)
polymerization in living cells
enzyme removes a hydroxyl group from one monomer and a hydrogen from another –> forms water as a by-product
2 monomers become joined by a covalent bond –> forms a dimer
monomers are added to the chain until it becomes long enough to be considered a polymer
hydrolysis
all chemical digestion consists of hydrolysis reactions
water molecule ionizes into OH- and H+
enzyme breaks the covalent bond linking one monomer to another and adds OH- to one monomer and H+ to the other
carbohydrate (def)
type of macromolecule
hydrophilic organic molecule
ex. sugars and starches
source of energy that can be quickly mobilized
monosaccharides (def and 3 primary of importance)
simplest carbohydrates –> monomers –> simple sugars
glucose, galactose, fructose
disaccharides (def and 3 primary of importance)
sugars composed of 2 monosaccharides
sucrose (glucose + fructose)
lactose (glucose + galactose)
maltose (glucose + glucose)
oligosaccharides (def)
short chains of 3+ monosaccharides
polysaccharides (def)
up to thousands of monosaccharides long
glycogen (def)
energy-storage polysaccharide
long, branched, glucose polymer
starch (def)
energy-storage polysaccharide of plants
the only significant digestible polysaccharide in the human diet
cellulose (def)
structural polysaccharide that gives strength to the cell walls of plans
composed of a chain of a few thousand glucose monomers
we can’t digest it –> absorbs water and helps clear GI tract
how do carbs get turned into ATP?
carbs –> glucose –> ATP
carbs can be conjugated (explain)
carbs are often covalently bonded to proteins and lipids for other functions
carb functions:
monosaccharides:
glucose (function)
blood sugar – energy source for most cells
carb functions:
monosaccharides:
galactose (function)
converted to glucose and metabolized
carb functions:
monosaccharides:
fructose (function)
fruit sugar – converted to glucose and metabolized
carb functions:
disaccharides:
sucrose (function)
cane sugar – digested to glucose and fructose
carb functions:
disaccharides:
lactose (function)
milk sugar – digested to glucose and galactose
important in infant nutriiton
carb functions:
disaccharides:
maltose (function)
malt sugar – product of starch digestion, further digested to glucose
carb functions:
polysaccharides:
cellulose (function)
structural polysaccharide of plants; dietary fiber
carb functions:
polysaccharides:
starch (function)
energy storage in plant cells; energy source in human diet
carb functions:
polysaccharides:
glycogen (function)
energy storage in animal cells (liver, muscle, brain, uterus, vagina)
carb functions:
conjugated carbohydrates:
glycoprotein (function)
component of the cell surface coat and mucus, among other roles
carb functions:
conjugated carbohydrates:
glycolipid (function)
component of the cell surface coat
carb functions:
conjugated carbohydrates:
proteoglycan (function)
cell adhesion
lubrication
supportive filler of some tissues and organs
lipid (general traits)
hydrophobic organic molecule
usually composed of carbon, hydrogen, and oxygen
less oxidized than carbs so lipids have more calories/gram
5 primary type sof lipids in humans:
1) fatty acids
2) triglycerides
3) phospholipids
4) eicosanoids
5) steroids
lipid functions:
bile acids (function)
steroids that aid in fat digestion and nutrient absorption
lipid functions:
cholesterol (function)
component of cell membranes; precursor of other steroids
lipid functions:
eicosanoids (function)
chemical messengers b/n cells
lipid functions:
fat-soluble vitamins (A, D, E, and K)
involved in a variety fo functions including blood clotting, wound healing, vision, and calcium absorption
lipid functions:
fatty acids (function)
precursor of triglycerides; source of energy
lipid functions:
phospholipids (function)
major component of cell membranes; aid in fat digestion
lipid functions:
steroid hormones (function)
chemical messengers b/n cells
lipid functions:
triglycerides (function)
energy storage
thermal insulation
filling space
binding organs together
cushioning organs
a glucose polymer synthesized by liver, muscle, uterine, and vaginal cells that serves as an energy-storage polysaccharide is a ___ molecule
glycogen
groups of atoms that are added to carbon backbones and that give organic molecules a variety of unique properties are generally known as ___
functional groups
macromolecule (def)
any molecule of large size and high molecular weight
4 organic macromolecules
carbohydrates
proteins
lipids
nucleic acids
type of macromolecule that is a major component of the plasma membrane
phospholipids
estrogen and testosterone are examples of which type of liquid?
steroids
polysaccharide used for energy storage in animals
glycogen
lipid (describe ratio of atoms in it)
way more H’s than O’s
___ is the general term for a lipid molecule that consists of 4 interconnected carbon rings. Examples are cholesterol, testosterone, or estrogen.
steroid
the ___ level of protein structure is determined by the folding of the protein due to hydrogen bonding b/n amino acids to form alpha helices and beta-pleated sheets
secondary
the folding of proteins into various globular and fibrous shapes is referred to as the ___ structure of the proteins
tertiary
which 3 functional groups are part of the basic structure of every amino acid?
amino group
radical (R) group
carboxyl group
what does a quaternary structure of a protein depend on?
interactions b/n multiple polypeptide chains
a ___ is the substance that an enzyme acts upon
substrate
an ___ is a protein that functions as a biological catalyst
enzyme
the lock and key model describes the property of enzyme-substrate ___
specificity
each step in a pathway is usually regulated by a specific ___
enzyme
what is a nucleotide composed of?
nitrogenous base
monosaccharide
phosphate group
sucrase digests ___
only sucrose
ATP (adenosine triphosphate) consists of…
adenine
ribose
3 phosphate groups
what is the toxic end-product of anaerobic fermentation?
lactic acid
term used to describe a series of reactions, where each step is catalyzed by a specific enzyme
metabolic pathway
energy molecule that is produced by cellular respiration and used in metabolic reactions
ATP
