Praxis II general science

anything that has mass and occupies volume
matter is made up of atoms and molecules
ionic nature of matter
Ions are formed when atoms, or groups of atoms, lose or gain electrons.
Metals lose some of their electrons to form positively charged ions, e.g. Fe+2, Al+3, Cu+2, etc.
Nonmetals gain electrons and form negatively charged ions, e.g. Cl-, O-2, S-2, etc.
physical properties of matter
Physical property changes of matter do not produce a new substance
Intensive: the same regardless of the amount of matter
* density: m/v
* color: The pigment or shade
* conductivity: electricity to flow through the substance
* malleability: if a substance can be flattened
* luster: how shiny the substance looks
melting and freezing point
Extensive: will change if the amount of matter changes.
* mass: how much matter in the sample
* volume: How much space the sample takes up
* length: How long the sample is
chemical properties of matter
any of a material’s properties that becomes evident during a chemical reaction-any quality that can be established only by changing a substance’s chemical identity
* Reactivity against other chemical substances
* Heat of combustion
* Enthalpy of formation
* Toxicity
* Chemical stability in a given environment
* Flammability
* Preferred oxidation state(s)
* Coordination number
* Capability to undergo a certain set of transformations, for ex chemical combination, redox reactions
* Preferred types of chemical bonds to form, for example metallic, ionic, covalent
organization of matter
pure substance: no separation by physical means
chemical element: pure chemical substance consisting of one type of atom distinguished by its atomic number, which is the number of protons in its nucleus
chemical compound: pure chemical substance consisting of two or more different chemical elements that can be separated into simpler substances by chemical reactions
Solutions: molecules that are mixed up in a completely even distribution, homogenous systems
mixture: substances held together by physical forces, not chemical, can be homogeneous and heterogeneous
A homogeneous mixture is called a solution
pure chemical substance, one type of atom, distinguished by its atomic number (Z), the number of protons in its nucleus
# of protons determines chemical properties
Mass number (A) is the number of nucleons (p+N) in nucleus
Oxygen most abundant on earth, Hydrogen most abundant in universe
Elements with atomic numbers 83 or higher are inherently unstable, and undergo radioactive decay
The abundance of the lightest elements is well predicted by the standard cosmological model, since they were produced shortly after the Big Bang, in a process known as Big Bang nucleosynthesis. Heavier elements were mostly produced much later, inside stars.
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chemical change
* Decomposition
* Neutralization (Mixing acid+base=water and a salt).
* Photosynthesis -co2 and water are changed into sugars.
* Cooking examples: cake, pancakes, and eggs/bacon
* Oxidation examples: rust or tarnishing
* Ripening examples: bananas, tomatoes or potatoes
* Change of odor
* Change of color
* Change in temp or energy, such as the production (exothermic) or loss (endothermic) of heat.
* Change of form (for example, burning paper).
* Light, heat, or sound is given off.
* Formation of gases, often appearing as bubbles.
* Formation of precipitate (insoluble particles).
* The decomposition of organic matter (for ex rotting food).
How did Dalton’s atomic theory help support the law of conservation of mass?
According to Dalton’s atomic theory :
1. All matter is made up of atoms
3. Atoms of the same element are identical
4. Atoms of different elements have different properties
5. compounds consisted of atoms of different elements combined together in a particular ratio
forms of energy
heat, light, sound, electrical, chemical, nuclear and mechanical
Work is the amount of energy transferred during an interaction
amount of energy before a transformation = amount of energy after. In most energy transformations, some energy is converted to thermal energy.
fusion vs fission
fission splits a massive element into fragments, releasing
energy in the process.
Fusion joins two light elements, forming a
more massive element, and releasing energy in the process
They both release energy because of the binding energy per nucleon curve
conversion of mass to energy
In the special theory of relativity Einstein demonstrated that neither mass nor energy were conserved separately, but that they could be traded one for the other and only the total “mass-energy” was conserved. The relationship between the mass and the energy is e=mc2
the speed of light squared is a very large number, a small amount of mass corresponds to a huge amount of energy
forms of energy
Energy is found in different forms including light, heat, chemical, and motion. There are many forms of energy, but they can all be put into two categories: potential and kinetic.
potential energy
Potential energy is stored energy and the energy of position — gravitational energy
*Chemical Energy is energy stored in the bonds of atoms and molecules
*Mechanical Energy is energy stored in objects by tension.
*Nuclear Energy is energy stored in the nucleus of an atom — the energy that holds the nucleus together.
*Gravitational Energy is energy stored in an object’s height.
Electrical Energy is what is stored in a battery
Kinetic energy
Kinetic energy is motion
*Radiant Energy is electromagnetic energy that travels in transverse waves
*Thermal Energy, or heat, is the vibration and movement of the atoms and molecules within substances.
*Motion Energy is energy stored in the movement of objects. The faster they move, the more energy is stored
*Sound is the movement of energy through substances in longitudinal (compression/rarefaction) waves
specific heat
is the measure of the energy required to increase the temperature of a unit quantity of a substance by a unit of temperature. For example, the energy required to raise water’s temperature by one kelvin (equal to one degree Celsius) is 4186 J/kg.
first law of thermodynamics
an expression of the principle of conservation of energy, states that energy can be transformed (changed from one form to another), but cannot be created or destroyed. It is usually formulated by saying that the change in the internal energy of a system is equal to the amount of heat supplied to the system, minus the amount of work done by the system on its surroundings.
second law of thermodynamics
an expression of the universal principle of decay observable in nature.
It is measured and expressed in terms of a property called entropy, stating that the entropy of an isolated system which is not in equilibrium will tend to increase over time or (equivalently) that perpetual motion machines are impossible.
is a macroscopic property of a system that is a measure of the microscopic disorder within the system
Antoine Lavoisier
discovered the law of conservation of mass and defined an element as a basic substance that could not be further broken down by the methods of chemistry
John Dalton
used the concept of atoms to explain why elements always react in ratios of small whole numbers (the law of multiple proportions) and why certain gases dissolve better in water than others. He proposed that each element consists of atoms of a single, unique type, and that these atoms can join together to form chemical compounds. Dalton is considered the originator of modern atomic theory.
Dmitri Mendeleev
In 1869, building upon earlier discoveries by such scientists as Lavoisier, Dmitri Mendeleev published the first functional periodic table. The table itself is a visual representation of the periodic law, which states that certain chemical properties of elements repeat periodically when arranged by atomic number
cathode rays
The physicist J. J. Thomson, through his work on cathode rays in 1897, discovered the electron, and concluded that they were a component of every atom. Thus he overturned the belief that atoms are the indivisible
plum pudding model
J. J. Thomson postulated that the low mass, negatively charged electrons were distributed throughout the atom, possibly rotating in rings, with their charge balanced by the presence of a uniform sea of positive charge.
gold foil experiment
In 1909, bombarded a sheet of gold foil with alpha rays—by then known to be positively charged helium atoms—and discovered that a small percentage of these particles were deflected through much larger angles than was predicted using Thomson’s proposal. suggesting that the positive charge of a heavy gold atom and most of its mass was concentrated in a nucleus at the center of the atom—the Rutherford model
Niels Bohr-orbitals
in 1913, physicist Niels Bohr suggested that the electrons were confined into clearly defined, quantized orbits, and could jump between these, but could not freely spiral inward or outward in intermediate states.An electron must absorb or emit specific amounts of energy to transition between these fixed orbits. When the light from a heated material was passed through a prism, it produced a multi-colored spectrum. The appearance of fixed lines in this spectrum was successfully explained by these orbital transitions
Bohr model
depicts the atom as a small, positively charged nucleus surrounded by electrons that travel in circular orbits around the nucleus—similar in structure to the solar system, but with electrostatic forces providing attraction, rather than gravity.
The model also violates the uncertainty principle in that it considers electrons to have known orbits and definite radius, two things which can not be directly known at once
electron configuration
The electron configuration of an atom is the particular distribution of electrons among available shells. It is described by a notation that lists the subshell symbols, one after another. Each symbol has a superscript on the right giving the number of electrons in that subshell. For example, a configuration of the lithium atom (atomic number 3) with two electrons in the 1s subshell and one electron in the 2s subshell is written 1s^2 2s^1.
The number of electrons in an atom of an element is given by the atomic number of that element
periodicity: atomic radius
One periodic property of atoms is that they tend to decrease in size from left to right across a period of the table. the atomic radii increases top to bottom and right to left in the periodic table.
periodicity: ionization energy
The energy needed to remove the most loosely held electron from an atom is known as ionization energy. Ionization energies are periodic. The ionization energy tends to increase as atomic number increases in any horizontal row or period. In any column or group, there is a gradual decrease in ionization energy as the atomic number increases. Metals typically have a low ionization energy. Nonmetals typically have a high ionization energy.
periodicity:electron affinity
The attraction of an atom for an electron is called electron affinity. Metals have low electron affinities while nonmetals have high electron affinities. The general trend as you go down a column is a decreasing tendency to gain electrons. As you go across a row there is also a trend for a greater attraction for electrons.
chemical reactivity: same period
*metal atoms tend to transfer electrons to nonmetals
*nonmetal atoms tend to gain or share electrons
In the same period:
smaller the number of electrons transferred, more vigorous reaction
chemical reactivity: same group
In the same group:
elements have the same # of outershell electrons, the atomic radius largely determines reactivity.
*larger metals loose outer shell electrons more easily
*smaller nonmetals are more likely to take electrons away/share w metals
atomic radius
the radii generally decrease along each period (row) of the table, from the alkali metals to the noble gases
increase down each group (column).
The radius increases sharply between the noble gas at the end of each period and the alkali metal at the beginning of the next period. These trends of the atomic radii (and of various other chemical and physical properties of the elements) can be explained by the electron shell theory of the atom; they provided important evidence for the development and confirmation of quantum theory.
charge of types of radiation
alpha rays carry a positive charge
beta rays carry a negative charge
gamma rays are neutral
alpha decay
mass number A and atomic number Z
An alpha particle (A=4, Z=2) emitted from nucleus
daughter is A-4 (top number) and Z-2 (bottom number)
beta decay
A nucleus emits an electron and an antineutrino
daughter is A, Z-1
mass number A and atomic number Z
gamma decay
Excited nucleus releases a high-energy photon (gamma ray)
daughter is the same A,Z
the speed of an object is the magnitude of its velocity (the rate of change of its position); it is thus a scalar quantity.
the rate of change of displacement (position). It is a vector quantity; both magnitude and direction are required to define it. The scalar absolute value (magnitude) of velocity is speed
v = delta x / delta t
The rate of change of velocity is acceleration – how an object's speed or direction changes over time, and how it is changing at a particular point in time.
average speed
The average speed of an object in an interval of time is the distance traveled by the object divided by the duration of the interval
free fall
A free falling object is an object that is falling under the sole influence of gravity
All free-falling objects (on Earth) accelerate downwards at a rate of 9.8 m/s/s
terminal velocity
an object is moving at its terminal velocity if its speed is constant due to the restraining force exerted by the air, water or other fluid through which it is moving.

A free-falling object achieves its terminal velocity when the downward force of gravity (Fg) equals the upward force of drag (Fd). This causes the net force on the object to be zero, resulting in an acceleration of zero- continues falling at a constant speed. More drag means a lower terminal velocity, increased weight means a higher

the number of occurrences of a repeating event per unit time. The period is the duration of one cycle in a repeating event, so the period is the reciprocal of the frequency.
ex: 1 year is the period of the Earth’s orbit around the Sun, and the Earth’s rotation on its axis has a frequency of 1 rotation per day.
independent variable
the variable representing the value being manipulated or changed
It is customary to use x for the independent variable
dependent variable
the dependent variable is the observed result of the independent variable being manipulated.
It is customary to use y for the dependent variable
newton’s first law of motion
“An object at rest will remain at rest, and an object moving at a constant velocity will continue moving at a constant velocity, unless it is acted upon by an unbalanced force.” Another name is Law of Inertia
newton’s second law of motion
A body of mass m subject to a force F undergoes an acceleration a that has the same direction as the force and a magnitude that is directly proportional to the force and inversely proportional to the mass, i.e., F = ma
newton’s third law of motion
The mutual forces of action and reaction between two bodies are equal, opposite and collinear. This means that whenever a first body exerts a force F on a second body, the second body exerts a force −F on the first body. F and −F are equal in magnitude and opposite in direction. This law is sometimes referred to as the action-reaction law, with F called the “action” and −F the “reaction”.
*the resistance an object has to a change in its state of motion*
The tendency of an object to resist changes in its state of motion varies with mass. A more massive object has a greater tendency to resist changes in its state of motion.
amount of energy transferred by a force acting through a distance. Like energy, it is a scalar quantity, with SI units of joules
the force that opposes the motion of one surface as it moves across another surface
a quantity that is often understood as the ability to perform work. This quantity can be assigned to any particle, object, or system of objects as a consequence of its physical state.
Different forms of energy include kinetic, potential, thermal, gravitational, sound, elastic and electromagnetic energy.
energy transformations
Any form of energy can be transformed into another form. When energy is in a form other than thermal energy, it may be transformed with good or even perfect efficiency, to any other type of energy. With thermal energy, however, there are often limits to the efficiency of the conversion to other forms of energy, due to the second law of thermodynamics
simple machine
a mechanical device that changes the direction or magnitude of a force. In general, they can be defined as the simplest mechanisms that use mechanical advantage (also called leverage) to multiply force
6 simple machines
* Lever
* Wheel and axle
* Pulley
* Inclined plane
* Wedge
* Screw
Simple machines fall into two classes; those dependent on the vector resolution of forces (inclined plane, wedge, screw) and those in which there is an equilibrium of torques (lever, pulley, wheel).
(kg·m/s, or N·s) is the product of the mass and velocity of an object (p = mv)
conservation of momentum
Since momentum is always conserved, the sum of the momenta before the collision must equal the sum of the momenta after the collision
There are two types of collisions that conserve momentum: elastic collisions, which also conserve kinetic energy, and inelastic collisions, which do not.
force due to gravity between two objects
Fg = G (m1 x m2) / r2

Fg – is the force due to gravity
G – is the universal gravitational constant
m1 – is the mass of the first object
m2 – is the mass of the second object
r – is the distance between the centres of the two objects

When using the SI units, G is 6.67 x 10-11 N m2 / Kg2

Archimedes principal
for a sunken object the volume of displaced fluid is the volume of the object, and for a floating object on a liquid, the weight of the displaced liquid is the weight of the object.
Buoyancy = weight of displaced fluid
Bernoulli’s principal
states that for an inviscid flow, an increase in the speed of the fluid occurs simultaneously with a decrease in pressure or a decrease in the fluid’s potential energy

**as the velocity of a fluid increases, the pressure exerted by that fluid decreases
why planes fly

loudness vs pitch
Loudness is a function of the sound wave’s amplitude. The greater the amplitude, the greater the volume. Pitch is related to its frequency. The higher the frequency, the higher the pitch.
A mole is the quantity of anything that has the same number of particles found in 12.000 grams of carbon-12.
That number of particles is Avogadro’s Number, which is roughly 6.02×10^23
a mole of any pure substance has a mass in grams exactly equal to that substance’s molecular or atomic mass; e.g., 1mol of calcium-40 is approximately equal to 40g,
Determine the empirical formula
for a compound which is 54.09% Ca, 43.18% O, and 2.73% H
Divide each percent by that element’s atomic weight. To get the answers to whole numbers, divide through by the smallest one.
Ca = 54.09/40 = 1.352 1.352/1.352 = 1
O = 43.18/16 = 2.699 2.699/1.352 = 2
H = 2.73/1 = 2.73 2.73/1.352 = 2
CaO2H2 =
gram atomic mass
The mass of one mole of atoms of an element. Also called gram-atomic weight.
process or reaction that releases energy usually in the form of heat, but also in the form of light (e.g. a spark, flame, or explosion), electricity (e.g. a battery), or sound(e.g. burning hydrogen)
process or reaction that absorbs energy in the form of heat.
specific heat of water
The specific heat of water is 1 calorie/gram °C = 4.186 joule/gram °C
real image
Real images can be produced by concave mirrors and converging lenses.
the image produced on a detector in the rear of a camera, and the image produced on a human retina (the latter two pass light through an internal convex lens).
wavelength changes frequency remains constant
resistors in parallel
have the same potential difference v1=v2=v3 etc..
power dissipated by a resistor is equal to current times the potential difference p=IV
freezing point of a solution
depends on the concentration of ions in solution as well as other factors.
For a solution with a liquid as solvent, the temperature at which it freezes to a solid is slightly lower than the freezing point of the pure solvent. This phenomenon is known as freezing point depression and is related in a simple manner to the concentration of the solute.
haploid number (n)
Human germ cells (sperm and egg) have one complete set of chromosomes from the male or female parent. Germ cells, also called gametes, combine to produce somatic cells. Somatic cells therefore have twice as many chromosomes. The haploid number (n) is the number of chromosomes in a gamete. A somatic cell has twice that many chromosomes (2n).
meiosis vs mitosis
mitosis=genetically identical diploid cells
meiosis=genetically unique haploid cells
autosomal recessive
An autosomal recessive disorder means two copies of an abnormal genegene must be present in order for the disease or trait to develop.
r/K selection theory
trade off between quantity or quality of offspring.
where r is the growth rate of the population (N), and K is the carrying capacity of its local environmental setting. Typically, r-selected species exploit less-crowded ecological niches, and produce many offspring, each of which has a relatively low probability of surviving to adulthood. In contrast, K-selected species are strong competitors in crowded niches, and invest more heavily in fewer offspring
fixed action pattern
an instinctive behavioral sequence that is indivisible and runs to completion. Fixed action patterns are invariant and are produced by a neural network known as the innate releasing mechanism in response to an external sensory stimulus known as a sign stimulus or releaser (a signal from one individual to another)
a class of relationship between two organisms where one organism benefits but the other is unaffected
cattle egrets foraging in fields among cattle or other livestock. As cattle, horses, and other livestock graze on the field, they cause movements that stir up various insects. As the insects are stirred up, the cattle egrets following the livestock catch and feed upon them. The egrets benefit from this relationship because the livestock have helped them find their meals, while the livestock are typically unaffected by it.
the solid part of the earth consisting of the crust and outer mantle
the envelope of gases surrounding any celestial body
the watery layer of the earth’s surface including water vapor
the layer closest to Earth, where almost all weather occurs; the thinnest layer. begins at the surface and extends to between 7 km (23,000 ft) at the poles and 17 km (56,000 ft) at the equator. Is mostly heated by transfer of energy from the surface, so on average temperature decreases with altitude. This promotes vertical mixing
the layer of the atmosphere that lies between the troposphere and the mesosphere and in which temperature increases as altitude increases; contains the ozone layer. jets fly.
after the stratosphere, before thermosphere.
where most meteors burn up upon entering the atmosphere. Temperature decreases with height. The mesopause, the temperature minimum that marks the top of the mesosphere, is the coldest place on Earth and has an average temperature around −85 °C (−121 °F; 188.1 K). Due to the cold temperature, water vapor is frozen, forming ice clouds (or Noctilucent clouds). A type of lightning referred to as either sprites or ELVES, form many miles above thunderclouds in the troposphere.
the biggest of all the layers of the earth’s atmosphere directly above the mesosphere and directly below the exosphere. Within this layer, ultraviolet radiation causes ionization. The International Space Station has a stable orbit within the middle of the thermosphere, between 320 and 380 kilometres (200 and 240 mi). Auroras also occur in the thermosphere.
outermost layer of Earth’s atmosphere extends from the exobase upward. Here the particles are so far apart that they can travel hundreds of km without colliding with one another. Since the particles rarely collide, the atmosphere no longer behaves like a fluid. These free-moving particles follow ballistic trajectories and may migrate into and out of the magnetosphere or the solar wind. The exosphere is mainly composed of hydrogen and helium.
ozone layer
a layer in Earth's atmosphere which contains relatively high concentrations of ozone (O3). This layer absorbs 97-99% of the sun's high frequency ultraviolet light, which is potentially damaging to life on earth. It is located in the lower portion of the stratosphere
Ozone concentrations are greatest between about 20 and 40 km, where they range from about 2 to 8 parts per million. If all of the ozone were compressed to the pressure of the air at sea level, it would be only a few millimeters thick
Precambian Eon
period of time from the formation of the Earth (4.6 billion years ago) to the rise of life forms
geologic time
The largest defined unit of time is the supereon, composed of eons. Eons are divided into eras, which are in turn divided into periods, epochs and ages
Phanerozoic Eon
the time since the formation of life-forms to the present day; divided into three eras: Paleozoic, Mesozoic, and Centzoic
Paleozoic Era
early life (570-286 million years ago); single cell organisms, shells, mollusks, brachiopods, rise of first vertebrates, rise of land plants, amphibians, insects, seed plants, and trees, and reptiles
Mesozoic Era
middle life (245-144 million years ago); rise of mammals and dinosaurs; the rise of birds; extinction of dinosaurs, rise of flowering plants
Cenozoic Era
is the most recent of the three classic geological eras and covers the period from 65.5 million years ago to the present. Rise of mammals, homo sapiens. marked by the Cretaceous-Tertiary extinction at the end of the Cretaceous, the demise of the dinosaurs and the end of the Mesozoic Era. is divided into two periods, the Tertiary and the Quaternary
single-celled organism without nuclei (bacteria)
single-celled organism with nuclei (algae, protozoans)
Linnean classification system
Kingdom, Phylum, Class, Order, Family, Genus, Species (Kings Play Chess On Fine Glass Surfaces; King Phillip Came Over For Good Spaghetti)
taxonomic rank below Kingdom and above Class. “Phylum” is equivalent to the botanical term division, Informally, phyla can be thought of as grouping organisms based on general body plan, as well as developmental or internal organizations. ex: Chordata, the phylum to which humans belong, along with all other vertebrate species, as well as some invertebrates such as the lamprey
three-domain system
loosely based on the traditional five-kingdom system but divides the kingdom Monera into two “domains,” leaving the remaining eukaryotic kingdoms in the third domain.
on the basis of differences in 16S rRNA genes, these two groups and the eukaryotes each arose separately from an ancestor with poorly developed genetic machinery, often called a progenote.
To reflect these primary lines of descent, he treated each as a domain, divided into several different kingdoms.
three domains
Archaea- prokaryotic, no nuclear membrane, possess unique ancient evolutionary history for which they are considered some of the oldest species of organisms on Earth; traditionally classified as archaebacteria; often characterized by living in extreme environments
Bacteria Domain – prokaryotic, no nuclear membrane, traditionally classified as bacteria, contain most known pathogenic prokaryotic organisms
Eukarya Domain – eukaryotes, nuclear membrane
characteristics of all living things
homeostasis, organization, metabolism, growth, adaptation, response to stimuli, reproduction
“cellular power plants” they generate most of the cell’s supply of adenosine triphosphate (ATP) through respiration, used as a source of chemical energy- citric acid cycle, or the Krebs Cycle
the mitochondrion has its own independent genome.its DNA shows substantial similarity to bacterial genomes.
non membrane bounded organelles responsible for protein synthesis from all amino acids
The DNA sequence in genes is copied into a messenger RNA (mRNA). Ribosomes then read the information in this RNA and use it to create proteins. This process is known as translation
membrane-enclosed organelle found in eukaryotic cells. It contains most of the cell’s genetic material, organized as multiple long linear DNA molecules in complex with a large variety of proteins to form chromosomes. maintains the integrity of these genes and controls the activities of the cell by regulating gene expression
non-membrane bound structure composed of proteins and nucleic acids found within the nucleus mainly involved in the assembly of ribosomes. After being produced in the nucleolus, ribosomes are exported to the cytoplasm where they translate mRNA
A vacuole is a membrane bound organelle which is present in all plant and fungal cells and some protist, animal and bacterial cells. are essentially enclosed compartments filled with water containing inorganic and organic molecules, isolating harmful material, waste products, maintain turgor,
endoplasmic reticulum
translation and folding of new proteins in rough endoplasmic reticulum- is covered with ribosomes, expression of lipids in smooth endoplasmic reticulum, single membrane compartment, all eukaryotes
Golgi apparatus
sorting and modification of proteins, single membrane compartment, all eukaryotes
breakdown of large molecules (e.g., proteins + polysaccharides)
involved in the organization of the mitotic spindle and in the completion of cytokinesis
an organelle that serves as the main microtubule organizing center of the animal cell as well as a regulator of cell-cycle progression Although the centrosome has a key role in efficient mitosis in animal cells, it is not necessary
cell cycle
series of events that takes place in a cell leading to its division and duplication (replication)
In cells with a nucleus (eukaryotes), the cell cycle can be divided in two periods: interphase—during which the cell grows, accumulating nutrients needed for mitosis and duplicating its DNA—and the mitosis (M) phase, during which the cell splits itself into two distinct cells, often called “daughter cells”.
phase of the cell cycle in which the cell spends the majority of its time and performs the majority of its purposes including preparation for cell division, increases its size and makes a copy of its DNA. gets itself ready for mitosis or meiosis
mitotic m phase
mitosis separates the chromosomes in its cell nucleus into two identical sets in two nuclei. It is followed by cytokinesis, which divides the nuclei, cytoplasm, organelles and cell membrane into two cells. Mitosis and cytokinesis together define the mitotic (M) phase of the cell cycle – the division of the mother cell into two daughter cells, genetically identical to each other and to their parent cell.
stages are interphase, prophase, prometaphase, metaphase, anaphase and telophase. During the process of mitosis the pairs of chromosomes condense and attach to fibers that pull the sister chromatids to opposite sides of the cell. The cell then divides in cytokinesis, to produce two identical daughter cells.
ionic compound
usually composed of metal cations and nonmetal anions, are electrically neutral, usually solid crystals at room temp, high melting point
*not named with prefixes
molecular compound
made up of molecules, nonmetallic, solid liquid or gas, low melting point ex: carbon monoxide, water
*only compound named with prefixes
two or more atoms of the same element, electrically neutral, smallest unit of a substance that retains the properties of that substance ex: O2
metals, positive, name is same as element like sodium cation Na+ and atomic sodium Na
nonmetals, negative, name typically ends in -ide like sulfide
compounds that produce hydrogen ions when dissolved in water, combination of anions connected to as many hydrogen ions as are needed to make the molecule electrically neutral
naming binary compound
*name ends in -ide
*if nonmetallic it is binary molecular; use prefix (N2O3 dinitrogen trioxide)
*If metallic and in group A name ions (BaS barium sulfide)
*if metallic not group A name ions and use roman numeral with cation (FeCl2 iron (II) chloride)
compound is an acid?
Starts with “H” (HNO3 nitric acid)
name a polyatomic ion compound
*name ends with -ite or -ate
*First element in group A, name the ions (Li2CO3 lithium carbonate)
*not in group A, name the ions use roman numerals with the cation (CuSO4 copper (II) sulfate)
-ite or -ate
polyatomic ion that included oxygen in the formula
indicates a binary compound- two nonmetallic elements, prefixes are used to indicate how many atoms of each are present
gram atomic mass
mass of one mole (6.02×10^23 atoms) of an element
gram molecular mass
mass of one mole of a molecular compound
gram formula mass
mass of one mole of an ionic compound
molar mass
mass in grams of one mole of the substance
*multiply the number of moles of a substance by the molar mass to get the mass of the substance
*divide mass of substance by molar mass to get number of moles
one mole of any gas at STP
occupies a volume of 22.4 L
(STP= 1atm pressure, 0deg C)
*density of any gas at STP is its molar mass divided by 22.4 L
IUPAC nomenclature of organic compounds: alkanes
compounds that consist only of the elements carbon (C) and hydrogen (H) (i.e., hydrocarbons), wherein these atoms are linked together exclusively by single bonds (i.e., they are saturated compounds).
take the suffix “-ane” and are prefixed depending on the number of carbon atoms in the chain
1=meth, 2=eth, 3=prop ex:methane propane butane
IUPAC nomenclature: alkenes and alkynes
**Alkenes are unsaturated compound containing at least one carbon to carbon double bond
Alkenes are named for their parent alkane chain with the suffix “-ene” and an infixed number indicating the position of the double-bonded carbon in the chain
**Alkynes have a tripple bond between two carbons
are named using the same system, with the suffix “-yne” indicating a triple bond
IUPAC nomenclature: alcohols
Alcohols (R-OH) take the suffix “-ol” with an infix numerical bonding position prefix hydroxy-
IUPAC nomenclature: amines
Amines (R-NH2) organic compounds and functional groups that contain a basic nitrogen atom with a lone pair.
are named for the attached alkane chain with the suffix “-amine” (e.g. CH3NH2 Methyl Amine)
ex: amino acids
synonym of saccharide, organic compound with the empirical formula Cm(H2O)n, that is, consists only of carbon, hydrogen and oxygen, with the last two in the 2:1 atom ratio.
divided into four chemical groupings: monosaccharides & disaccharides (sugars end in -ose), oligosaccharides, and polysaccharides (starch glycogen cellulose)
covalent bond
when electrons are shared to form an octet
between atoms with same electronegativity, nonpolar
between atoms with differing electronegativity, polar
hydrogen bond
a hydrogen covalently bonded to a very electronegative atom is also weakly bonded to an unshared electron pair of another electronegative atom, strong relative to other dipole interactions
ionic bond
involves a metal and a nonmetal ion (or polyatomic ions such as ammonium) through electrostatic attraction. In short, it is a bond formed by the attraction between two oppositely charged ions.
metallic bond
preferable to use the term metallic bonding, because this type of bonding is collective in nature and a single “metallic bond” does not exist, electrons are shared over many nuclei allows for electrical conductivity
ideal gas law
combination of Boyle’s law and Charles’s law. It can also be derived from kinetic theory.
The state of an amount of gas is determined by its pressure, volume, and temperature. The modern form of the equation is:

pV = nRT

where p is the absolute pressure of the gas; V is the volume; n is the amount of substance; R is the gas constant; and T is the absolute temperature.

boyles law
For a fixed amount of an ideal gas kept at a fixed temperature, P [pressure] and V [volume] are inversely proportional (while one increases, the other decreases)
charles law
At constant pressure, the volume of a given mass of an ideal gas increases or decreases by the same factor as its temperature on the absolute temperature scale (i.e. the gas expands as the temperature increases)
a kind of redox reaction in which any combustible substance combines with an oxidizing element, usually oxygen, to generate heat and form oxidized products
redox reaction
which atoms have their oxidation number (oxidation state) changed. This can be either a simple redox process, such as the oxidation of carbon to yield carbon dioxide (CO2) or the reduction of carbon by hydrogen to yield methane (CH4), or a complex process such as the oxidation of sugar(C6H12O6) in the human body through a series of complex electron transfer processes.
* Oxidation
is the loss of electrons or an increase in oxidation state by a molecule, atom, or ion.
* Reduction
is the gain of electrons or a decrease in oxidation state by a molecule, atom, or ion.
Electroplating is a plating process that uses electrical current to reduce cations of a desired material from a solution and coat a conductive object with a thin layer of the material, such as a metal. The part to be plated is the cathode of the circuit. The anode is made of the metal to be plated on the part. Both components are immersed in a solution electrolyte containing one or more dissolved metal salts that permit the flow of electricity. A power supply supplies a direct current to the anode, oxidizing its metal atoms, dissolving in the solution. At the cathode, the dissolved metal ions in the electrolyte solution are reduced at the interface between the solution and the cathode, such that they “plate out” onto the cathode.
meiosis one
refers to “reduction division” because homologues chromosomes separate and the 2 haploid daughter cells have only half the chromosome number
homologous chromosome
chromosome pairs of the same length, centromere position, and staining pattern with genes for the same characteristics at corresponding loci. One homologous chromosome is inherited from the organism’s mother, the other from the organism’s father.
meiosis 1 phases
prophase 1, metaphase 1, anapahse 1, telophase 1 and cytokinesis
meiosis 2 phases
Prophase II Metaphase II Anaphase II Telophase II
prophase one
prophase one
*Chromosomes condense and attach to the nuclear envelope.
*Synapsis occurs (pair of homologous chromosomes lines up closely together), tetrad is formed, tetrad is composed of four chromatids.
*Crossing over may occur.
*Chromosomes thicken and detach from the nuclear envelope
*centrioles migrate away from one another and both the nuclear envelope and nucleoli break down
*chromosomes begin their migration to the metaphase plate
crossing over
exchange of sections of genetic material between homologous chromosomes during prophase I of meiosis
metaphase one
metaphase one
Tetrads align at the metaphase plate.
Tetrads align at the metaphase plate.
the centromeres of homologous chromosomes are oriented toward the opposite cell poles.
the paired chromosomes consisting of four chromatids
the region of the chromosome that holds the two sister chromatids together during mitosis
anaphase one
anaphase one
*Chromosomes move to the opposite cell poles. Similar to mitosis, the microtubules and the kinetochore fibers interact to cause the movement.
Unlike in mitosis, the homologous chromosomes move to opposite poles yet the sister chromatids remain together.
sister chromatids
Replicated forms of a chromosome joined together by the centromere and eventually separated during mitosis or meiosis II.
telophase one
telophase one
The spindles continue to move the homologous chromosomes to the poles.
Once movement is complete, each pole has a haploid number of chromosomes
In most cases, cytokinesis occurs at the same time as telophase I.
At the end of telophase I and cytokinesis, two daughter cells are produced, each with one half the number of chromosomes of the original parent cell.
Depending on the kind of cell, various processes occur in preparation for meiosis II. There is however a constant: The genetic material does not replicate again.
prophase two
the disappearance of the nucleoli and the nuclear envelope again as well as the shortening and thickening of the chromatids. Centrioles move to the polar regions and arrange spindle fibers for the second meiotic division
metaphase two
* The chromosomes line up at the metaphase II plate at the cell’s center.
* The kinetochores of the sister chromatids point toward opposite poles.
the centromeres contain two kinetochores that attach to spindle fibers from the centrosomes (centrioles) at each pole. The new equatorial metaphase plate is rotated by 90 degrees when compared to meiosis I, perpendicular to the previous plate
meiosis II
Meiosis II is the second part of the meiotic process. Much of the process is similar to mitosis. The end result is production of four haploid cells (23 chromosomes, 1N in humans) from the two haploid cells (23 chromosomes, 1N * each of the chromosomes consisting of two sister chromatids) produced in meiosis I. The four main steps of Meiosis II are: Prophase II, Metaphase II, Anaphase II, and Telophase II
anaphase two
where the centromeres are cleaved, allowing microtubules attached to the kinetochores to pull the sister chromatids apart. The sister chromatids by convention are now called sister chromosomes as they move toward opposing poles.
telophase two
is similar to telophase I, and is marked by uncoiling and lengthening of the chromosomes and the disappearance of the spindle. Nuclear envelopes reform and cleavage or cell wall formation eventually produces a total of four daughter cells, each with a haploid set of chromosomes. Meiosis is now complete and ends up with four new daughter cells.
meiosis generates genetic diversity
in two ways: (1) independent alignment and subsequent separation of homologous chromosome pairs during the first meiotic division allows a random and independent selection of each chromosome segregates into each gamete; and (2) physical exchange of homologous chromosomal regions by homologous recombination during prophase I results in new combinations of DNA within chromosomes.
Mitosis is the process by which a eukaryotic cell separates the chromosomes in its cell nucleus into two identical sets in two nuclei.[1] It is generally followed immediately by cytokinesis, which divides the nuclei, cytoplasm, organelles and cell membrane into two cells containing roughly equal shares of these cellular components.
cell cycle
a cell grows (G1), continues to grow as it duplicates its chromosomes (S), grows more and prepares for mitosis (G2), and finally it divides (M) before restarting the cycle.
In plant cells only. In highly vacuolated plant cells, the nucleus has to migrate into the center of the cell before mitosis can begin. This is achieved through the formation of a phragmosome, a transverse sheet of cytoplasm that bisects the cell along the future plane of cell division. the formation of a ring of microtubules and actin filaments (called preprophase band) underneath the plasma membrane around the equatorial plane of the future mitotic spindle.
mitosis prophase
(Normally, the genetic material in the nucleus is in a loosely bundled coil called chromatin)
*chromatin condenses together into a highly ordered structure called a chromosome.
*genetic material has already been duplicated earlier in S phase
*replicated chromosomes have two sister chromatids, bound together at the centromere by the cohesion complex
mitosis prometaphase
The nuclear envelope disassembles and microtubules invade the nuclear space. This is called open mitosis, and it occurs in most multicellular organisms.
Each chromosome forms two kinetochores at the centromere, one attached at each chromatid.
a complex protein structure that is analogous to a ring for the microtubule hook; it is the point where microtubules attach themselves to the chromosome
When a microtubule connects with the kinetochore, the motor activates, using energy from ATP to “crawl” up the tube toward the originating centrosome. This motor activity provides the pulling force necessary to later separate the chromosome’s two chromatids.
In the fishing pole analogy, the kinetochore would be the “hook” that catches a sister chromatid or “fish”. The centrosome acts as the “reel” that draws in the spindle fibers or “fishing line”.
mitosis metaphase
the centromeres of the chromosomes convene along the metaphase plate or equatorial plane, an imaginary line that is equidistant from the two centrosome poles
mitosis anaphase
proteins that bind sister chromatids are cleaved, separating into distinct sister chromosomes.
they are pulled apart by shortening kinetochore microtubules and move toward the respective centrosomes to which they are attached.
Next, the nonkinetochore microtubules elongate, pulling the centrosomes (and the set of chromosomes to which they are attached) apart to opposite ends of the cell.
These two stages are sometimes called early and late anaphase
mitosis telophase
is a reversal of prophase events. It “cleans up” the after effects of mitosis.
the nonkinetochore microtubules continue to lengthen, elongating the cell even more. Corresponding sister chromosomes attach at opposite ends of the cell. A new nuclear envelope forms around each set of separated sister chromosomes.
Both sets of chromosomes, now surrounded by new nuclei, unfold back into chromatin. Mitosis is complete, but cell division is not yet complete.
is a homogeneous mixture composed of two or more substances. In such a mixture, a solute is dissolved in another substance, known as a solvent. ratio of solute to solvent stays the same, won’t settle out. Substance present in larger amount is solvent.
Solvents can be gases, liquids, or solids. The solution has the same physical state as the solvent.
point at which a solution of a substance can dissolve no more of that substance and additional amounts of it will appear as a precipitate. This point of maximum concentration, the saturation point, depends on the temperature of the liquid, pressure, contaminates, as well as the chemical nature of the substances involved.The solubility of liquids in liquids is generally less temperature-sensitive than that of solids or gases.
super saturation
a solution that contains more of the dissolved material than could be dissolved by the solvent under normal circumstances.
are prepared or result when some condition of a saturated solution is changed, for example temperature, volume (as by evaporation), or pressure
Carbonated water is a supersaturated solution of carbon dioxide gas in water. At the elevated pressure in the bottle, more carbon dioxide can dissolve in water than at atmospheric pressure. At atmospheric pressure, the carbon dioxide gas escapes very slowly from the supersaturated liquid. This process may be accelerated by the presence of nucleation sites within the solution, such as small bubbles, caused by shaking the bottle, or another solute, such as sugar powder or a widget. A Diet Coke and Mentos eruption is a rather extreme example.
*is any substance containing free ions that make the substance electrically conductive.
*most typical is an ionic solution
*commonly exist as solutions of acids, bases or salts
*normally formed when a salt is placed into a solvent such as water and the individual components dissociate due to the thermodynamic interactions between solvent and solute molecules, in a process called solvation
a compound unable to ionize and does not conduct electricity
the process of attraction and association of molecules of a solvent with molecules or ions of a solute.
As ions dissolve in a solvent they spread out and become surrounded by solvent molecules
involves different types of intermolecular interactions: hydrogen bonding, ion-dipole, and dipole-dipole attractions or van der Waals forces.
hydrogen bonding, ion-dipole, and dipole-dipole interactions occur only in polar solvents. Ion-ion interactions occur only in ionic solvents
distinct from dissolution and solubility. Dissolution is a kinetic process, and is quantified by its rate. Solubility quantifies the dynamic equilibrium state achieved when the rate of dissolution equals the rate of precipitation.
reacts with metals and carbonates, turns blue litmus paper red, and has a pH less than 7.0 in its standard state
Acids can occur in solid, liquid or gaseous form, depending on the temperature. They can exist as pure substances or in solution
Reactions of acids are often generalized in the form
HA <--> H+ + A−
where HA represents the acid and A− is the conjugate base. Acid-base conjugate pairs differ by one proton, and can be interconverted by the addition or removal of a proton
the stronger of two acids will have a higher disassociation constant (k suba)
pKa = -log10 Ka. Stronger acids have a smaller pKa than weaker acids
oxidation state
assigned by computing the difference between the number of valence electrons that a neutral atom of that element would have and the number of electrons that “belong” to it in the Lewis structure.
electrons in a bond between atoms of different elements belong to the most electronegative atom; electrons in a bond between atoms of the same element are split equally, and electrons in a lone pair belong only to the atom with the lone pair.
while in ions the algebraic sum of the oxidation states of the constituent atoms must be equal to the charge on the ion.
naming acids
are named according to their anions. That ionic suffix is dropped and replaced with a new suffix (and sometimes prefix). For example, HCl has chloride as its anion, so the -ide suffix makes it take the form hydrochloric acid.
strong vs weak acid
refers to its ability or tendency to lose a proton. A strong acid is one that completely dissociates in water; in other words, one mole of a strong acid HA dissolves in water yielding one mole of H+ and one mole of the conjugate base, A−, and none of the protonated acid HA