Atom
Smallest particle of an element
non polar covalent bond
equal sharing of electrons
polar covalent bond
unequal sharing of electrons
covalent bond
A chemical bond formed when two atoms share electrons
intermolecular bonding
bonding between molecules
intramolecular bonding
bonds within molecules
hydrogen bond
Attraction between a slightly positive hydrogen atom and a slightly negative atom.
Solvent
a liquid that dissolves another substance
Solutes
substance dissolved in a solution
Concentration
the amount of a solute that is dissolved in a given amount of water
Acids
a proton donor or a substance that releases hydrogen ions (H+) into a solution
Bases
a proton acceptor or a substance that can bind H+ in a solution
Buffers
help stabilize pH
Lipids
non-polar and therefore do not interact easily
Triglycerides
fat; used in the body to store energy as well as insulate the body and pack organs; hydrophobic
phospholipids
amphipathic which means they have both polar and non-polar regions
steroids
hormones; produced from cholesterol
monosaccharides
glucose, fructose, galactose
disaccharides
sucrose, lactose, maltose
polysaccharides
Carbohydrates that are made up of more than two monosaccharides; starch
glycogen
the only polysaccharide humans produce
Carbohydrates
primarily used for energy and are the molecules the body uses first as a source of energy
Nucleic acids
monomer of nucleotides which combine to form DNA + RNA
ATP
a nucleotide that cells use as energy to do cellular work
Denaturation
result of high temperatures (high fevers) or high or low pH; the loss of the three-dimensional shape of a protein is known as denaturation
Potential Energy
stored energy; ex: covalent bonds
Kinetic Energy
energy in motion; ex: heat, sound, mechanical, or electromagnetic (light)
Chemical reactions
a breaking or making of bonds
metabolism
All chemical reactions in an organism
reactant
one or more substances that enter into the reaction
product
one or more substances produced by a chemical reaction
Reaction Rate
the speed of a reaction or the rate at which products are made
synthesis reaction
chemical reaction that results in the joining of components that were formerly separate; anabolic reactions
degradation reaction
a chemical reaction that results in the breakdown of a larger molecule into at least two smaller molecules
Hydrolysis
a reaction type that is responsible for breaking down polymers
Endergonic reactions
those in which chemical bonds are created; therefore, energy was added in the chemical reaction; synthesis reactions
Exergonic reactions
those in which energy is released as chemical bonds are broken; degradation reactions
Enzymes
all proteins; end in -ase
metabolic pathway
cellular chemistry is usually broken up into small steps requiring many enzymes
substrate
Enzymes have to physically stick to (bind) the reactants
active site
part of the enzyme that binds to the substrate
inhibitors
can prevent enzymes from doing their job; toxins
competitive inhibitor
bind to the active site and physically block the substrate from binding
non-competitive inhibitor
bind to a different site of the enzyme, called the allosteric site
conformational change
A change in the shape of an active site
Enzyme concentration
Increasing enzyme concentration will increase the reaction rate
Substrate concentration
will increase the reaction rate up the point that all enzymes are bound to substrate (saturated) and can not work any faster.
Temperature
Lower the temperature will decrease the rate of the reaction because it reduces the likelihood of the enzyme and substrate binding. Increasing the temperature will increase the reaction rate until the temperature is so high it causes the enzyme to denature and no longer able to function
pH
Raising or lowering the pH of solution too drastically can cause the enzyme to denature, resulting in the slowing and stopping of the reaction
cellular respiration
The overall set of reactions
mitochondria
energy and carbon dioxide is produced; Krebs cycle, produces ATP
oxidative phosphorylation
electron transport chain; mitochondria
Cells
perform maintenance, recycle, and eliminate wastes
Cytoplasm
everything that is found within a cell excluding the nucleus. The cytoplasm is broken down into organelles and the cytosol which is the fluid within the cell. Cytosol is commonly referred to as intracellular fluid (ICF)
ISF
Almost all human cell types are bathed in a fluid termed interstitial fluid
hydrophilic
the head of a phospholipid molecule that is attracted to water
hydrophobic
the tail of a phospholipid molecule that is repelled by water
Glycoprotein
A protein with one or more covalently attached carbohydrates.
Glycolipids
a lipid with one or more covalently attached carbohydrates
simple diffusion
Small molecules like O2, CO2 (nonpolar molecules), and water can get across by squeezing between the phospholipids; high to low concentration; No APT is required
facilitated diffusion
Larger molecules like glucose, amino acids, and all ions (e.g. Na+, K+, Ca2+, etc.) will need the assistance of a protein to cross the membrane. These cells have special proteins embedded in their membranes called channels that allow ions to get through the membrane. No ATP is required. high concentration to low.
passive transport
no ATP; high to low concentration;
transporters
monosaccharides (glucose) or amino acids will enter the cell through transport proteins; high to low concentration
osmosis
Diffusion of water through a selectively permeable membrane; low to high concentration
tonicity
the difference in solute concentration between the cell and the surrounding solution
isotonic
If the cell and the solution have the same solute concentration
hypertonic
If the solution has more solute that the cell, water will be drawn out of the cell, This can cause red blood cells to crinkle up (crenate) and not flow properly
hypotonic
If the solution has less solute than the cell, water will be pulled into the cell, Red blood cells can swell (again, the wrong shape) and even burst (lyse).
active transport
the movement of materials through a cell membrane using energy; low to high concentration; requires ATP
pumps
membrane proteins that provide active transport of molecules across the membrane; creates concentration gradients. move ions (and other molecules) in the opposite direction to diffusion; low to high concentration. takes energy in the form of ATP
Vesicles
membrane bound sacs found in the cell
Endocytosis
process by which a cell takes material into the cell by infolding of the cell membrane
Phagocytosis
cell taking in a solid particle - think an immune cell eating a bacteria
Pinocytosis
cell taking in the liquid from around it - think cell drinking
Receptor
mediated endocytosis is the cell taking in only very specific substances.
Exocytosis
a process of a cell releasing a substance or substances from the cell
Lysosome
contains digestive enzymes which are used within the cell to perform functions such as digesting unwanted or damaged organelles
Rough endoplasmic reticulum and golgi apparatus
process, modify, and package proteins
Smooth endoplasmic reticulum
produce lipids needed by the cell such as phospholipids and detoxifies
Peroxisomes
lipid metabolism and chemical detoxification
Ribosomes
protein production
Nucleolus
produces ribosomes
Cytoskeleton
gives structure to the cell, organizes organelles
Centrosome
involved in cell division (mitosis and meiosis)
Proteasome
breaks down proteins
Membrane-bound organelles
Mitochondria, Lysosome, Rough endoplasmic reticulum and golgi apparatus, Smooth endoplasmic reticulum, Peroxisomes
Non-membrane bound organelles
Ribosomes, Nucleolus, Cytoskeleton, Centrosome, Proteasome
Microvilli
increase surface area for absorption and secretion
Cilia
move substances in one direction such as mucous (with trapped bacteria) towards the throat or movement of the egg towards the uterus
Flagella
in humans, only found as part of sperm for motility
Tight Junctions
much like sewing cells together and ensuring water and substances do not move between cells
Desmosomes
VERY strong connections between cells
Gap junctions
not very strong connections, but a pore is created that allows a signal to pass from one cell to the next extremely quickly
Mitosis
used for growth, replacement of cells, and repair; cells divide once which results in two genetically identical cells
interphase
cells are not dividing; they grow into G1 or G2; they replicate their chromosomes
cytokinesis
Division of the cytoplasm during cell division
Meiosis
results in four non-identical cells with only half of the genetic material the cell started with; only produces the male and female reproductive cells: sperm and ovum (eggs)
transcription
takes place in the nucleus; one of these genes is copied into the form of mRNA which can then leave the nucleus
Translation
process in which the mRNA is translated into an amino acid sequence (protein); translation takes place within the ribosome
karyotype
a systematic arrangement of chromosomes for easier visualization
sex chromosomes
X/Y pair; they dictate genetic sex of the individual and contain "sex-linked" traits
Allele
Different forms of a gene
genotype
An individual's genetic makeup
phenotype
the characteristic that is expressed by the genes
Gregor Mendel
found that some alleles mask or cover the expression of another allele
dominant allele
The allele that dominates or masks the other (D)
recessive allele
the allele that is masked (d)
homozygous
an individual with two of the same alleles of a trait
heterozygous
one dominant allele and one recessive allele
Autosomal Dominant Inheritance
When an individual inherits a disorder from their parents by receiving one copy of an abnormal gene
Autosomal Recessive Inheritance
When an individual inherits a disorder from their parents by receiving two copies of an abnormal gene
sex-linked traits
is one that is due to an abnormal gene on the X or Y chromosomes. These disorders affect males more than females because males have both and X and Y chromosomes; thus, if the abnormal gene is on the X, there is not another copy (another X) to make the proper protein. Also, since only males have a Y chromosome, if the abnormal gene is on the Y, the male will be affected.
Y-linked disorders
Y-linked disorders only affect males as only males have a Y chromosome. The Y chromosome comes from the father, so these disorders are inherited from the father
X-linked dominant disorders
X-linked dominant disorders affect both males and females as both have an X chromosome and the abnormal gene is found on the X chromosome
X-linked recessive disorders
X-linked dominant disorders affect both males and females as both have an X chromosome and the abnormal gene is found on the X chromosome; however, males are more likely to be affected as females have two alleles (one on each X chromosome) and a normal allele will mask the abnormal recessive allele. If a male offspring receives the abnormal allele, they will be affected (same as X-linked dominant).
Codominance
A, B, and O blood types have an alternative inheritance pattern; more than one allele may be expressed - in fact, all alleles present will be expressed
Homologous chromosomes
the same chromosome from a different parent
non-disjunction
where chromosomes fail to separate properly
Monosomy
caused by the deletion of a chromosome in one of the gametes (sperm or egg) and combined with a normal gamete. These disorders are fatal, results in miscarriage
Trisomy
caused by the addition of a chromosome in one gamete and combined with a normal gamete. Many of these are fatal and result in miscarriage, but if this affects a very small chromosome the individual could survive.
Trisomy 21
Down syndrome
ionic bond
bond found between two polar molecules
dehydration reaction
combines monomers
monomer for proteins
amino acids
anaerobic cellular respiration
produces lactic acid
cellular membrane is composed of
phospholipids
Mendelian inheritance
inheritance of freckles, dimples, etc. that follows a set pattern