Most Important Flashcards
(249 cards)
1
Q
Interphase
A
the phase of the cell’s life before mitosis; the cell carries out its function and duplicates its DNA
2
Q
Centromere
A
The center of a chromosome. Connects the two sister chromatids.
3
Q
Hypertonic
A
A condition in which the cell has a higher concentration of solutes than the environment
4
Q
Metaphase
A
the phase of mitosis in which the chromosomes line up down the middle of the cell
5
Q
Polymer
A
Multiple units of monomers bonded to form a macromolecule
Polypeptide Chain
6
Q
Centrosome
A
Pulls apart chromosomes during interphase
7
Q
Osmosis
A
The net movement of water (a solvent) from low solute concentration to high solute concentration. Does not require a cell to use energy.
If there is a higher concentration of sugar molecules outside of the cell, there will be net movement of water molecules out of the cell until the two sides are in equilibrium.
8
Q
Chromosome
A
DNA which is condensed into X-shaped structures; chromosomes are made of two halves called sister chromatids joined at the centromere in the middle
9
Q
Prometaphase
A
the phase of mitosis in which the nuclear membrane disappears
10
Q
Anaphase II
A
Chromosomes are pulled apart and separated again
11
Q
Chlorophyll
A
pigments that capture energy from solar radiation and power the chemical process
12
Q
Sister Chromatids
A
Two identical DNA strands, joined together by a centromere
13
Q
Respiration
A
process where organisms use food (such as sugar) to make useful energy and waste products
14
Q
Light-Dependent Reaction
A
Light is required to make the reaction occur such as sunlight that is converted to chemical energy in photosynthesis
15
Q
Mitosis
A
the cell cycle when the nucleus of a cell separates into two, resulting in two new daughter cells (somatic cells) with the same number of chromosomes as the parent cell
skin cells dividing, bacteria reproducing
16
Q
Lipids / Fats
A
large fat molecules used for energy storage; monomers are fatty acids and glycerol, which come together to form lipids such as phospholipids.
Fatty Acid
17
Q
Channel Proteins
A
Structures that allow passive transport of molecules across membranes
18
Q
Anaphase I
A
Chromosomes are pulled apart and separated
19
Q
Spindle Fibers
A
parts of the cytoskeleton which latch onto chromatids and pull them toward the centrioles during mitosis
20
Q
Glycolysis
A
Glucose is broken down into pyruvate and energy and CO2 are released
21
Q
Passive Transport / Diffusion
A
The net movement of solutes (particles in a solution) from high concentration to low concentration. Does not require a cell to use energy.
If there is a higher concentration of Na+ ions outside of the cell, there will be net movement of the ions into the cell until the two sides are in equilibrium.
22
Q
Enzyme / Catalyst
A
A type of protein that functions to reduces the amount of energy required to begin a reaction, therefore speeding up the reaction rate. It is not destroyed during the reaction.
23
Q
Calvin Cycle
A
Stage of photosynthesis where carbon dioxide is synthesized into sugar
24
Q
Chloroplast
A
organelle in plant cells where photosynthesis takes place; contains chlorophyll
25
Coefficient (in a Reaction)
Number placed in front of a molecule indicating how many are needed for a reaction
26
Cristae
Inner folds of the mitochondria where the ETC is located
27
Metaphase II
Chromosome align at the equator or metaphase plate. It looks like a line of single Xs.
28
Telophase
the phase of mitosis in which two nuclear membranes form
29
Anerobic
Reaction that does not use oxygen as an electron acceptor
Fermentation
30
Aerobic
Reaction that requires oxygen as an electron acceptor
Aerobic Respiration
31
Turgor Pressure
The force of water against the vacuole of a plant cell which allows it maintain a rigid appearance
32
Meiosis II
Second round of meiosis that results in gametes
33
Na+/K+-ATPase
An enzyme, also called the sodium potassium pump, that actively transports ions across the cell membrane and regulates osmotic pressure
34
Cytokinesis
the phase of mitosis or meiosis in which the cytoplasm divides
Formation of the cleavage furrow between two dividing animal cells
35
Prophase II
The chromosomes condense and centrosomes duplicate
36
Electron Transport Chain (ETC)
a cluster of proteins that transfer electrons through a membrane to form a gradient of protons that drives the creation of adenosine triphosphate (ATP)
37
Cell Plate
in plant cells, the organelle which grows in the middle to separate the two cells during mitosis.
38
Hypotonic
A condition in which the cell has a lower concentration of solutes than the environment
39
Prophase I
Chromosomes twist together and crossover DNA
40
Adenosine Triphosphate (ATP)
particle in the cell that captures released energy from cellular respiration and delivers it where needed
41
Concentration Gradient
The difference in concentration of a type of molecule across a cell membrane
42
Telephase I
New nuclear envelopes form around separated chromosomes
43
Centrioles
Centrioles
44
Kreb's Cycle
Pyruvate is broken down and CO2 and energy are released
45
Light-Independent Reaction
Reactions that can occur without light being present
46
Chromatids
the two arms that make up a chromosome; joined at the center region called a centromere
47
Prophase
the phase of mitosis in which the chromatin condenses into chromosomes, the centrioles move to opposite sides of the cell, and the nucleolus disappears
48
Daughter Cells
cells produced by cell division; in mitosis, these are genetically identical to the parent cells and to each other
49
Cleavage Furrow
in animal cells, the "pinching" of the cell into two cells occurs at this site
50
Somatic Cells
body cells which carry out life processes and are not used for sexual reproduction
skin cells, liver cells
51
Isotonic
A condition in which the cell has the same concentration of solutes as the environment
52
Photosynthesis
process by which plants use light, water, and carbon dioxide to make their own food (sugar) and oxygen
53
Diploid Cell
A cell that contains 2 sets of chromosomes (1 from father and 1 from mother)
54
Active Transport
Uses energy to move nutrients from low concentration to high concentration
55
Meiosis I
First round of meiosis that results in haploid cells
56
Turgid
The growth-inducing condition of a plant cell in a hypotonic environment
57
Metaphase I
Homologous chromosome align at the equator or metaphase plate. It looks like a line of pairs of Xs.
58
Proteins
Large biomolecules composed of amino acids (the monomers) that carry out many different cell functions. When broken down, release usable energy for the cell.
hemoglobin
59
Nucleic Acids
The biomolecule that forms DNA and RNA. The specific sequence of nucleic acids (the monomer) provides the genetic information of the organism.
DNA, RNA
60
Plasma Membrane / Cell Membrane
a soft membrane that encloses the cytoplasm of a cell. Movement of molecules in and out of the cell is regulated by proteins within this membrane.
61
Osmoregulation
The regulation of water in and out of cells
62
Telephase II
New nuclear envelopes form around separated chromosomes
63
Carbohydrates
macromolecules containing carbon, hydrogen, and oxygen; used as a quick source of energy; monomers are monosaccharides, which chain together to form polysaccharides.
sugar, starch
64
Monomer
Single units of macromolecules
Amino Acid
65
Chromatin
The spread out form of DNA seen during interphase
66
Ideal Gas Law
PV=nRT
67
Acidity
The concentration of hydrogen ions [H+] in a solution; high acidity corresponds to low pH.
hydrochloric acid (HCl)
68
Freezing Point Depression
Adding solute to lower the freezing temperature
Salting roads can prevent water from freezing at
0°C
69
Half-Life
The amount of time it takes for half of the isotopes in a sample to change
70
Reaction: Decomposition
1 molecule is broken down into 2 separate elements or molecules
71
Endothermic
In an endothermic process, a substance gains thermal energy.
In an endothermic reaction, the reactants absorb heat while rearranging chemical bonds.
As ice melts into water, it absorbs heat from the environment
72
Stoichiometry
uses a balanced chemical equation to determine the amount of reactants needed to create a certain amount of product or how much product can be created from a set amount of reactant
73
Reaction: Neutralization
Reaction in which when an acid and base chemically react and form a salt and water with a resulting pH of 7
74
Chemical Equilibrium
The state in which reactants and products are being formed at the same rate
75
Chemical Equations
Notation that shows how 2 molecules or compounds react together to form a product
76
Limiting Reagent / Limiting Reactant
The first chemical to be used up in a chemical reaction
77
Pressure
The force exerted on an object over a given area
78
Dimensional Analysis / Unit Analysis
the process of converting within or between systems by multiplying by factors of 1 in various forms
79
Standard Temperature and Pressure (STP)
A temperature and pressure of 273 K and 1 atm
80
Exothermic
In an exothermic process, a substance releases thermal energy.
In an exothermic reaction, the reactants release heat while rearranging chemical bonds.
As water freezes into ice, it releases heat into the environment
81
Chemical Reaction
a reaction that forms a new substance by rearranging the atomic bonds between atoms. The process absorbs energy during bond-breaking and releases energy during bond-making.
82
Activation Energy (Ea)
the amount of energy needed for a reaction to begin
83
Reaction: Combination
2 elements or molecules combine to form 1 molecule
84
Reaction: Oxidation/Reduction (Redox)
Reaction in which electrons transfer, causing the oxidation number to change
85
Dynamic Chemical Equilibrium
Equilibrium when a reversible reaction proceeds in both directions, so the net production is zero
86
Reaction: Combustion
A compound containing carbon reacts with oxygen and burns releasing carbon dioxide
87
Excess Reagent / Excess Reactant
The leftover reagent(s) in a chemical reaction after the limiting reagent is depleted.
88
Conservation of Matter
Matter cannot be created or destroyed; it only changes form
chemical reaction
89
Static Chemical Equilibrium
Equilibrium reached in an irreversible reaction that proceeds in one direction until all the reactants are used up
90
Oxidation Number
The charge on an atom
91
Reaction: Single Replacement
One element or molecule replaces another element in a molecule
92
Le Chatelier's Principle
The statement that a reaction shifts to counteract a change in concentration or temperature of the reactants
If the pressure on a reaction at equilibrium is increased, then the reaction will shift to produce fewer moles of gas.
93
Reaction: Double Replacement
Elements in molecules replace each other
94
Specific Heat (c)
eat energy required to raise the temperature of a substance with a given mass by a given number of degrees.
Δheat=mcΔT
95
Solute
The material in a solution that is dissolved in the solvent
The sugar in lemonade
96
Spontaneity
Whether or not a process will proceed without an additional energy input;
ΔG<0
97
Exothermic
In an exothermic process, a substance releases thermal energy.
In an exothermic reaction, the reactants release heat while rearranging chemical bonds.
As water freezes into ice, it releases heat into the environment
98
Calorimeter
A piece of equipment used to determine the heat change associated with a chemical reaction
99
Solvent
a substance which dissolves other substances
if salt is dissolved in water, water is the solvent.
100
Solubility
the ability of a substance to be dissolved
101
Endothermic
In an endothermic process, a substance gains thermal energy.
In an endothermic reaction, the reactants absorb heat while rearranging chemical bonds.
As ice melts into water, it absorbs heat from the environment
102
Dissolution
The separation of an ionic compound into a cation and anion
Breaking apart of ionic NaCl salt crystal in water.
103
Entropy (S)
A measure of the disorder of a system. The amount of thermal energy that cannot be used to do mechanical work as a system moves toward equilibrium.
104
Enthalpy (H)
The quantity of heat in a system
105
Gibbs Free Energy (ΔG)
temperature and the change in entropy, measured in kJ per mol reaction
ΔG o=ΔH o−TΔS o
106
Enthalpy of Solution / Enthalpy of Dissolution (ΔHsoln)
The heat that is absorbed or released when a solute dissolves into solution.
In an exothermic dissolution, the interactions between the solute particles are weaker than the interactions between solute and solvent particles. The ΔHsoln is negative.
In an endothermic dissolution, the interactions between solute particles are stronger than the interactions between solute and solvent particles. The ΔHsoln is positive.
107
Standard Gibbs Free Energy of Formation (ΔGfo)
The change in energy that results from the formation of 1 mole of chemical from its component elements at 298 K
108
Compression Wave
a longitudinal wave with areas of high and low pressure, or density
sound
109
Amplitude
the maximum displacement of a particle of the medium during a vibration (measured from non-vibrating position to one crest)
height of an ocean wave above the ocean's normal surface height
110
Intensity
a measure of the severity or volume of a behavior when it occurs
A teacher notes that over time, with coaching and reminders, an autistic student's verbal self-stimulation has gotten quieter and less disruptive.
111
Doppler Effect
An increase in the frequency (or pitch) when a sound emitter and/or an observer move toward each other and a decrease in the frequency (or pitch) when the objects move apart.
Police radar
112
Frequency
the number of ocurrences of an observed behavior over a set time period
A teacher counting the number of times Jacob sticks his tongue out at a classmate during a one-hour class would be collecting frequency data.
113
Mechanical Waves
Physical waves that travel through a medium.
sound, water waves
114
Wave
a disturbance that transports energy as it moves through space and time
water wave, electromagnetism, sound
115
Wave Speed
a measure of how fast the wave energy moves from one place to another
speed of light
116
Crests
the peaks, or highest points, of a vertically vibrating transverse wave
117
Threshold of Hearing
0 dB, the softest sound a human can hear
118
Pitch
how high or low the sound seems to a human ear
119
Troughs (of a Wave)
the valleys, or lowest points, of a vertically vibrating transverse wave
120
Period
the time it takes to complete one full wave cycle, measured in seconds
a 17 second stop-light cycle
121
Threshold of Pain
sound at 120 dB
122
Transverse Wave
a wave in which the direction of the vibration is perpendicular to the direction the energy travels
light, vibrating guitar string
123
Electromagnetic Spectrum
the entire range of frequencies of electromagnetic waves from very long radio waves to very short gamma rays
infrared, ultraviolet
124
Decibel
The unit for the loudness of sound and is abbreviated dB.
125
Loudness
human perception of the intensity of a sound
industrial noise at 110 dB sounds very loud
126
Electromagnetic Waves
Waves consisting of vibrating electric and magnetic fields. Electromagnetic waves can travel through a vacuum because they do not require a medium. Emitted by all objects with a temperature above absolute zero.
light, radio waves, x-rays
127
Longitudinal Wave
a wave in which the direction of the vibration is parallel to the direction the energy travels
sound
128
Medium
the material that carries a mechanical wave
air for sound wave, a string for a violin
129
Wavelength
the length (in space) of one complete wave cycle, measured in distance units
crest to crest distance on a water wave
130
Asteroids
small, rocky bodies in the sun's orbit
Ceres
131
Mercury
the first planet from the sun; an inner planet (inside the asteroid belt); slightly larger than Earth's moon; experiences extreme temperature variations; large iron core
132
Retrograde Motion
Planetary motion that appears (from Earth's point of view) to have a rotation opposite that of Earth
133
Saturn
the sixth planet from the sun; an outer planet (outside the asteroid belt); the least dense planet; has a complex ring system
134
Earth
the third planet from the sun; an inner planet (inside the asteroid belt); only known habitable planet; 71% of surface covered with liquid water
135
Satellite
an object or body that orbits another object or body
Earth's moon
136
Solar Flare
A burst of high-energy radiation from the Sun's surface that is associated with sunspots.
137
Uranus
the seventh planet from the sun; an outer planet (outside the asteroid belt); composed mostly of rock and ice; has 27 named moons
138
Solar System
A star, as well as the planets, satellites, asteroids, and all the other objects orbiting it. They travel together through space.
139
Constellations
a star grouping which forms a pattern; we have ascribed images to the constellations
Orion
140
Photosphere
The opaque, innermost visible layer of the Sun that surrounds the convective zone
141
Period (of a Comet)
the amount of time it takes for a comet to orbit the sun
Halley's Comet has a period of about 75 years
142
Convective Zone
A layer of the Sun surrounding the radiative zone, in which convection currents carry heat to the Sun's surface.
143
Meteoroids
small bodies of debris from space which move into Earth's atmosphere and can then turn into meteors
144
Meteorite
what remains of a meteor after it hits the surface of the earth
145
Corona
The outer atmosphere of the Sun
146
Background Radiation
low temperature radiation that permeates all of space; thought to be a red-shifted remnant of the big bang.
147
Kuiper Belt
A flat disc of comets, asteroids, and other small icy objects that orbit the sun at a distance beyond Neptune
148
Accretion
the process by which smaller particles clumped together to form bigger and bigger masses, and eventually, planets like Earth
149
Chromosphere
The red-colored layer of the Sun that is on the outside of the photosphere.
150
Neptune
the eighth planet from the sun; an outer planet (outside the asteroid belt); methane in the atmosphere absorbs red light to make it appear blue; gives off over twice as much energy as it receives from the sun
151
Protoplanet Theory
the belief that planets were small, dense regions of a nebula that were captured by the gravity of a star
152
Mars
the fourth planet from the sun; an inner planet (inside the asteroid belt); the "Red Planet"; home to Olympus Mons, the tallest mountain in the solar system;
153
Plasma
a state of matter in which atoms have been stripped of their electrons; electrons move freely around a plasma
inside the sun
154
Core
Core
155
Pluto
previously classified as the ninth planet from the sun; usually now classified as a minor planet or dwarf planet; has five moons
156
Oort Cloud
a shell of comet bodies which orbit the sun
157
Redshift
A shift in the light from a star toward the red end of the visible spectrum that is produced when the star is moving away from Earth.
158
Jupiter
the fifth planet from the sun; an outer planet (outside the asteroid belt); largest planet; over twice as massive as all the other planets combined; has four large moons; about 90% hydrogen and 10% helium
159
Meteor
a meteoroid that has entered Earth's atmosphere
160
Sedna
another dwarf planet; much farther from the sun than Pluto; takes 10,000 years to orbit the sun
161
Comet
a body made of ice and dust in the sun's orbit; contains a gas and dust "tail"
Halley's Comet
162
Polaris
The name of the North Star; Earth's North Pole points toward the North Star
163
Planet
a body moving in orbit around a star; large enough to clear debris in its orbit; has enough gravity to make it round
Earth
164
Venus
the second planet from the sun; an inner planet (inside the asteroid belt); slightly smaller than Earth; similar density and chemical composition to Earth
165
Big Bang Theory
a theory about the origin of the universe which states that the universe was at one time a very small, very condensed, very massive particle; a large explosion forced all matter out at an extremely rapid rate, and the universe has continued to expand since
166
Dwarf Planet
a small planet not large enough to clear its orbit of debris
Pluto
167
Radiative Zone
A layer of the Sun surrounding the core, through which energy is slowly transported by radiation.
168
Battery
A device that uses chemical reactions to produce a voltage difference across two terminals.
Button battery
169
Step-Down Transformer
A transformer that decreases the voltage and increases the current by the same ratio
170
Electromagnet
a coil of wire that is magnetic because current flows through it
solenoid
171
Ideal Transformer
A transformer with no losses due to heating or other effects
172
Diamagnetism
The quality of materials that are weakly repelled by other magnets and are magnetic only when in an external magnetic field
Water
173
Generator
A device that uses electromagnetic induction to produce an electrical current (mechanical energy to electrical energy).
Generator within a windmill
174
Ferromagnetism
The quality of materials that form strong magnets and generally stay magnetized even when removed from an external magnetic field
Magnets of iron, cobalt, and nickel
175
Magnetic Field
The potential magnetic force in the space surrounding a magnet. Proportional to the force on a magnetic pole in the space around the magnet.
176
Magnetic Field Lines
Lines drawn to represent the direction and strength of a magnetic field.
177
Electromagnetic Induction
The process of inducing a current by moving charges through a magnetic field.
178
Transformer
A device that uses electromagnetic induction to proportionally change the values of AC current and voltage
Phone charger
179
Paramagnetism
The quality of materials that are weakly attracted to other magnets and are magnetic only when in an external magnetic field
Lithium
180
Primary Coil
Primary Coil
181
Secondary Coil
The output coil of a transformer, connected to the power user
182
Microchips
Small computers with limited functions; used as controllers and timers in electronic devices.
183
Solenoid
A coil of wire around a central iron piston.
184
Step-Up Transformer
A transformer that increases the voltage and decreases the current by the same ratio
Long distance power transmission
185
Electron
low-mass, negatively charged particle; surrounds the nucleus of an atom
186
Niche
the relationships and activities of an organism within its habitat
a red squirrel's niche: eats nuts, lives within the hollows of trees, and drinks water from streams
187
Intraspecific Competition
competition between members of the same species
two male bighorn sheep fighting for a mate
188
Biotic Factors / Biological Factors
Factors in an ecosystem which are or once were living
plants, animals, dead tree leaves
189
Omnivore
an organism that eats both plants and animals for energy and nutrients.
a mouse will eat both insects and seeds
190
Top-Down Control
The type of control that predators have on the population of prey
191
Limiting Factor
a resource whose presence or absence determines the growth of a population
nitrogen, phosphorus, and potassium in the soil
192
Interspecific Competition
competition between different species
leopards and lions in sub-Saharan Africa competing for prey
193
Bottom-Up Control
The type of control that resources such as food have on a population or community.
194
Biodiversity
The number of different types of species in an area
A rainforest has higher biodiversity than the artic.
195
Herbivore
an organism that eats only plants for energy and nutrients. Also called a primary consumer.
grasshopper
196
Decomposer
an organism that breaks down dead matter for energy and nutrients. Returns unused nutrients to the soil.
fungi (mushroom)
197
Secondary Consumer
an organism in a food chain that eats primary consumers. May be omnivores or carnivores.
lizard
198
Consumer
an organism which depends on another organism to provide the energy it needs to survive; assigned a trophic level depending on what kinds of organisms it eats
wolf
199
Food Web
show the flow of energy through an ecosystem through a complex network of overlapping food chains
200
Logistic Growth (in ecology)
dramatic growth in populations until carrying capacity is reached, at which point growth levels out. This occurs in the presence of limited resources
wolf population in Yellowstone National Park
201
Migration / Gene Flow
movement of individuals of a species
202
Net Primary Production (NPP)
The rate at which inorganic carbon is converted to organic carbon by photosynthesis
203
Tertiary Consumer
an organism in a food chain that eats secondary consumers. May be omnivores or carnivores.
bear, snake
204
Primary Consumer
an organism in a food chain that eats the plants (producers). Herbivores.
grasshoppers
205
Carnivore
an organism that eats only other animals for energy and nutrients.
mountain lion
206
Exponential Growth (in ecology)
dramatic growth in populations in the presence of unlimited resources
bacteria growth in the lab
207
Carrying Capacity (K)
the number of organisms an ecosystem can support without breaking down
208
Keystone Species
species that plays a key role in the ecosystem by providing balance in most of the other populations, such as keeping omnivores in check by preying on them.
starfish in a kelp forest
209
Competition (Ecology)
struggle among organisms for basic needs such as space, water, food, and sunlight
two male lions fighting over a dead monkey
210
Trophic Level
the level in the food chain assigned to an organism based on what it eats
primary consumer
211
Apex Predator
an organism at the top of the food chain with little or no natural enemies
mountain lion
212
Producer
an organism that uses abiotic resources (like the sun's rays) to make food
grass
213
Adaptation
A feature that has become common in a population because it provides some improved function which makes the organism better able to survive and reproduce. It can be structural or behavioral.
migration in winter
214
Greenhouse Gases
gases which, when present in elevated quantities in Earth's atmosphere, trap solar radiation and cause the planet to warm
carbon dioxide
215
Extinction
the dying out of all members of a species
dodo birds
216
Natural Selection
The process by which, over time, the population as a whole contains more individuals which are better suited to that environment.
faster antelopes survive to pass down traits
217
Abiotic Factors / Physical Factors
Factors in an ecosystem which are not alive
temperature, precipitation, soil
218
Gyrochronology
A technique used by astronomers that uses a star's rotation rate and color to determine its age
219
Absolute Magnitude
the actual amount of light a star gives off
The absolute magnitude of our sun is 4.8
220
Singularity
An infinitely small, dense center of a black hole
221
Neutron Star
a small star with high density; made of closely packed neutrons
Crab Pulsar
222
Binary Stars
a two-star system; the stars rotate around a common point, or one star rotates around the other
Castor
223
Black Hole
an object with gravity great enough that it does not allow radiation or matter to escape
224
Hertzsprung-Russell Diagram
A temperature versus luminosity plot of different types of stars
225
Moons
satellites which orbit planets
Phobos
226
Celestial Bodies
a physical object in space which has observable characteristics
planet
227
Oort Cloud
a shell of comet bodies which orbit the sun
228
Distance Ladder
A series of techniques, that when used together help astronomers determine distances in space
229
Solar System
A star, as well as the planets, satellites, asteroids, and all the other objects orbiting it. They travel together through space.
230
Red/Blue Giants
large stars; red giants have high luminosity and low surface temperature; blue giants have high luminosity and high surface temperature
Rigel (blue giant)
231
Exoplanets
planets which orbit stars outside our own solar system
Proxima Centauri b
232
Big Bang
An sudden expansion of the Universe that produced an explosive growth in the size of the entire Universe that continues today
233
White Dwarf
a small star with high density; often the size of a planet
Sirius B
234
Meteoroids
small bodies of debris from space which move into Earth's atmosphere and can then turn into meteors
235
Cosmic Microwave Background Radiation
Microwave radiation at a temperature of 3K from every direction that fills the entire sky; thought to have cooled from very energetic radiation that originated during the inflationary period of the Universe
236
Comet
a body made of ice and dust in the sun's orbit; contains a gas and dust "tail"
Halley's Comet
237
Red/Blue Dwarfs
small stars; red dwarfs have low mass and low surface temperature; blue dwarfs develop from red dwarfs after the hydrogen is used up
Proxima Centauri
238
Stars
a gaseous body which produces radiant energy through nuclear fusion reactions
the sun; Sirius
239
Nebula
a gas and dust cloud in space
Orion Nebula
240
Galaxies
a system of stars and their systems held together by gravity
Milky Way Galaxy
241
Constellations
a star grouping which forms a pattern; we have ascribed images to the constellations
Orion
242
Planet
a body moving in orbit around a star; large enough to clear debris in its orbit; has enough gravity to make it round
Earth
243
Supernova
explosion of a high-mass star that blows off the outer layers and condenses the core
244
Hubble's Constant
A constant of proportionality between the distance and velocity of galaxies
H o ≈70 km/s/Mpc
245
Models
physical, mathematical, or visual representations of scientific phenomena
a diagram of the eye
246
Blueshift
A shift in the light from a star toward the blue end of the visible spectrum that is produced when the star is moving towards Earth.
247
Spectroscope
An instrument that splits light into separate wavelengths
Can be used to determine the composition of a star
248
Redshift
A shift in the light from a star toward the red end of the visible spectrum that is produced when the star is moving away from Earth.
249
Pulsar
a rapidly rotating neutron star; emits pulsing radio waves
Vela Pulsar
