Download Key Concepts for Organization of Living Things Three Domains of

Key Concepts for Organization of Living Things
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Three Domains of living things: Bacteria, Archaea, Eukarya
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Domains Bacteria and Archaea used to be called Kingdom Monera
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Kingdoms of eukaryotes:
o Plants – photosynthesize; roots transport nutrients and water from soil; stems transport stuff
through plant; leaves photosynthesize
 Mosses (no vascular tissue; must live in wet), Ferns (spores, no seeds), Gymnosperms
(e.g. conifers; seeds, but no flowers or fruit), Angiosperms (seeds, flowers, fruits)
o Animals – ingest organic matter (other organisms)
 Invertebrates (no backbone) most numerous
 Arthropods (Insects, arachnids, crustaceans), mollusks (clams, snails, octopi),
worms, jellyfish, echinoderms (starfish, sea urchins)
 Vertebrates
 Fish, amphibians (mix aquatic and terrestrial adaptations), reptiles and birds,
mammals
o Fungi – mushrooms, molds, yeast – mostly decomposers
o Protists – mostly single-celled; paramecium, amoeba, diatoms, dinoflagellates, algae
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Cell is the smallest unit of life; all organisms composed of at least one cell
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Plasma membrane is semipermeable
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Function of each organelle
o Chloroplast – photosynthesis
o Mitochondria – cellular respiration, make ATP
o Nucleus – contains the genetic information; “controls” cell
o Ribosomes – make protein
o Rough ER – studded with ribosomes, makes and packages protein
o Smooth ER – makes lipids; detoxifies
o Golgi – modifies and packages materials; sorts and send them to specific locations
o Lysosomes – breaks down cellular wastes
o Vacuole – fluid-filled compartment
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Differences between prokaryotic (bacteria and archaea) and eukaryotic – eukaryotic has nucleus and
membranous organelles (ER, Golgi, chloroplast, mitochondria)
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Differences between plant and animal cells – plant cells have chloroplasts, vacuoles, cell wall (animals
don’t)
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Osmosis – movement of water across membrane; cell in water with higher concentration of solutes will
shrink; in lower concentration will swell
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Mitosis produces exact copies of cells; used for growth and development; one cell division produces two
cells
o Prophase, Metaphase (middle), Anaphase (chromosomes split), Telophase
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Meiosis produces gametes (sperm and eggs); gametes have half the # chromosomes of body cells; two
consecutive divisions of one cell produces four
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Photosynthesis – captures solar energy and carbon from gaseous CO2 (taken in through leaves) from
the atmosphere and stores them in an organic form in molecules of glucose, which plants use as their
energy source; the process also requires water (as an electron donor) that the plant takes in through the
roots
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Cellular respiration produces ATP by breaking down the organic molecules like glucose and capturing
the energy stored in them; requires oxygen as an electron acceptor; produces water and CO 2 as waste;
all eukaryotes (including plants) perform cellular respiration
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Human Life cycle: gestation, birth, adulthood
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Plant Life cycle: seed – germination followed by – seedling – mature plant – flower
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Complete metamorphosis (e.g. butterfly) – egg, larva, pupa, adult
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Incomplete metamorphosis (e.g. grasshopper) – egg, larva (or nymph), adult
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Living things require air, water, nutrition, habitat
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Cell, tissue, organ, organ system
o Circulatory – transports nutrients, water, wastes, oxygen (heart, arteries, veins)
o Digestive – breaks down food for energy; produces feces (mouth, esophagus, stomach, small
intestine, large intestine, anus, pancreas, liver)
o Excretory – maintains water balance; produces urine (kidneys, ureter)
o Endocrine – hormomes
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Immune – defense
Integumentary – hair, skin, nails
Muscular – movement by contraction of muscles
Nervous – receives stimuli, initiates response (brain, spinal cord, nerves, neurons)
Respiration – oxygen in, carbon dioxide out (nose, mouth, pharynx, trachea, lungs)
Reproductive – produce offspring (testes, ovaries)
Skeletal – supports and protects
Key Concepts for Heredity
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Gene is a piece of DNA that codes for a protein
o DNA transcribed to RNA and translated to Protein [Central Dogma]
o A bonds with T; G bonds with C
o Three bases in mRNA is codon; codes for one amino acid in the protein
 Sexual reproduction
o Adult meiosis gametes fertilization zygote mitosis offspring
 Genetics
o Two copies of the gene for each trait; Different forms of a gene = allele
o Homozygous – both alleles the same; Heterozygous – alleles different
o Dominant allele is expressed in heterozygote; Recessive is not
o Genotype = the alleles you have; Phenotype = the form of the trait you express
o Punnett Square
o Inherited traits come from DNA from parents in egg or sperm
o Acquired traits are not controlled by genes
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Artificial selection – humans breed species for preferred traits – don’t create new traits, just select
among those present
Key Concepts for Evolution
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Natural Selection
o Organisms have inherited traits, controlled by genes
o Individuals in the same species have different traits
o Those individuals with the best adapted traits reproduce more than the others
o Those adaptive traits increase in frequency
o Leads to changes in populations; the become better adapted to their environments
o Not based on “need” and can not cause new traits to occur
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Adaptations
o Morphological – shape, size, structure, color
o Physiological – types and efficiencies of chemical reactions in the body
o Behavioral – behaviors; learned vs innate; only those that are genetically controlled are acted
on by natural selection
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Evidence
o Fossil record; Homologous structures; DNA similarities; Embryological similarities; Distribution
of related speces
Key Concepts for Ecology
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Population Growth
o Exponential – fast, unregulated,J-shaped
o Logistic – competition, levels off, S-shaped
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Interspecific Interactions
o Mutualism (+,+), Competition (-, -), Predation (predator/prey, herbivory, parasitism (+,-)
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Niche – Species’ role in a community; Habitat – species location in an ecosystem; determined by abiotic
(non-living – e.g. temp, pH, water) and biotic (other organisms) interactions
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Food chains and Webs
o Producers photosynthesize; Consumers (herbivores, omnivores, carnivores) eat other
organisms, Decomposers break down wastes and dead organisms
o 10% of energy passes from one trophic level to the next
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Energy flows through ecosystems (not reused, lost as heat); Chemicals are cycled (e.g. water cycle,
carbon cycle)
o Energy flow and carbon cycling are driven by photosynthesis and cellular respiration
Physical Science Concepts
Key Concepts: Nature of Matter
 Matter is anything that is made of atoms.
 Atoms have protons (+) and neutrons (0) in the nucleus; electrons (-) orbit in shells (2,8,8) – if the
outer shell is full, atom is stable and won’t react
 # protons = atomic number; atomic mass = protons + neutrons
 element = only one type of atom; molecules = atoms bonded together; compound = atoms of
different types bonded together
 solution – homogeneous mixture
 ionic bond – transfer of electron creates oppositely charged atoms, attraction = bond
 Covalent bond – shared pair of electrons
 Hydrogen bond – attractions between partially charged regions of molecules; polar
 Water, because of hydrogen bonds – cohesive, surface tension, high heat capacity, more dense
when liquid, good solvent
 pH – acidic = more H+ ions (pH<7); basic = more OH- ions (pH>7)
 Periodic table is arranged by # of electrons in outer shell
 Matter (atoms) cannot be created or destroyed
 States of matter – solid, liquid, gas – rate of particle motion and spacing increase
 Solid to liquid = melting; liquid to solid = freezing; liquid to gas = evaporation; gas to liquid =
condensation; gas to solid = deposition; solid to gas = sublimation
 In chemical reactions, bonds are broken and atoms are rearranged
 Balancing equation – because atoms are neither created nor destroyed
 Mass = amount; weight = measure of gravity pulling on the mass
 Volume = space something takes up; density = mass per unit volume; specific gravity = density
compared to water
 Physical property = how it looks, smells, feels, how much of it there is; physical change can be
reversed
 Chemical property = how does it react; structure of the atoms; chemical change can not be
reversed
 Organic compounds – carbon
 Gases: Increase pressure, decrease volume, increase temperature; decrease pressure, increase
volume, decrease temperature
Key Concepts: Energy
 Work = force x distance
 Energy can do work; potential energy = stored energy; kinetic energy = motion
 1st law - energy can’t be created or destroyed
 2nd law – entropy increases (the amount of usable energy decreases)
 Types of energy – light, sound, heat, electromagnetic, chemical, electrical, gravitational,
mechanical
 Heat = total energy; Temperature = rate of molecular motion
 Convection – movement of warmed matter
 Conduction – transfer of energy from particle to particle
 Radiation – electromagnetic waves transport energy through space
Key Concepts: Force and Motion
 Gravitational force – masses exert on each other; electromagnetic force – between charged
particles; nuclear strong force – holds nucleus together against repelling protons; nuclear
weak force – changes flavors of quarks
 Velocity = change in distance over time; acceleration = change in velocity over time;
Momentum = mass x velocity
 Newton 1 – body remains at rest or motion unless acted on by force
 Newton 2 – Force = mass x acceleration; objects with greater mass require more force to
move them
 Newton 3 – every action is countered by an equal and opposite reaction
 Simple machines change the direction or magnitude of the force required to do work, making
the work require less energy – inclined plane, wedge, level, wheel and axle, screw, pulley
 Friction – surfaces rub against each other, resistance to motion
Key Concepts: Electricity
 Electrical charges – attraction between opposite charges; current is flow of electrons; magnetic
fields – opposites attract; like repel
 A circuit is an unbroken loop of conductive material that allows electrons to flow through
continuously without beginning or end.
 If a circuit is "broken," that means its conductive elements no longer form a complete path, and
continuous electron flow cannot occur in it.
Key Concepts: Waves
 Wavelength – distance peak to peak; amplitude – how “high”?; frequency = how fast?
 Sound – amplitude = how loud; wavelength/frequency = how high or low the pitch
 Doppler – as you approach the source of sound, wavelength compressed, sounds higher; as
you go away from source, wavelength seems longer, lower
 Light – wavelength/frequency = what “color”; amplitude = intensity
 Reflection – bouncing back; refraction – changing angle
 Convex lens converges light; concave lens diverges light
 Electromagnetic spectrum [short to long] – gamma, x-rays, ultraviolet, visible, infrared, radio;
visible [short to long] – red, orange, yellow, green, blue, purple
People in Science
• Newton – laws of motion; gravity; Mendel – genetics; Pasteur – airborne disease; Darwin –
evolution; Einstein – relativity; Bernoulli – energy in fluids and air; Mendeleev – periodic table;
Hutton – age of earth
Metric
 Mass – gram; Volume – liter; Length – meter; Milli – 1000th; Centi – 100th; Kilo – 1000
Scientific Method
 Observation, Hypothesis, Testable Prediction, Controlled Experiment, Conclusions...
Communicate results
 Controlled experiment – control group and experimental group: as similar as possible except
for the one thing you are manipulating to test; replication – multiple subjects, multiple trials
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