Transcript #1 Scientific Method

#1 Scientific Method
• Steps that scientists use to gather
information and answer questions.
• Problem/Question, Hypothesis,
Experiment, Conclusion, Theory
• Data-quantitative (numbers) or qualitative
(descriptions)
#2 Hypothesis
• Explanation for a question or a problem
that can be formally tested.
• Sometimes an “If…then” statement.
• Educated guess.
#3 Bias
• Personal and unscientific judgment that
may alter the results of an experiment.
• Opinion or belief
#4 Independent Variable
• In an experiment, the condition that is
changed because it affects the outcome of
the experiment.
• Manipulated variable.
#5 Dependent Variable
• In an experiment, the condition that results
from changes in the independent variable.
• Measured variable.
#6 Metric System
• Mass- gram-triple beam balance
• Length- meter- meter stick
• Volume- liter- graduated cylinder
#7 Heterotroph
• An organism that must consume its food. It
cannot produce its own.
• Consumer.
• Herbivore, carnivore or omnivore.
#8 Autotroph
• An organism that can produce its own
food.
• Uses photosynthesis or chemosynthesis.
• Producer.
#9 Biology
• Study of living things.
• Animals, plants, bacteria
#10 Biotic
• Living part of an ecosystem.
• Ex. Plants, animals, fungi, bacteria
#11 Abiotic
• Nonliving part of an ecosystem.
• Air, water, soil
#12 Homeostasis
• Maintaining a stable internal environment.
• Including body temperature and amount of
water and nutrients.
#13 Metabolism
• All of the chemical reactions that take
place in an organism.
#14 Characteristics of living things
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Made of cells
Reproduce
Have DNA
Grow/Develop
Obtain and use energy
Respond to environment (Homeostasis)
Adapt
#15 Atoms
• Made of protons (+), neutrons(0), and
electrons (-).
• Protons and neutrons in nucleus,
electrons are in electron cloud.
• Can form bonds to make molecules and
compounds.
#16 Bonds
• Covalent Bonds- share valence electrons
• Ionic bonds- formed by oppositely
charged ions; + & • Hydrogen bonds- weak covalent bonds
between hydrogen atoms; found in water
and DNA
#17 Ions
• An atom that has a positive or negative
charge
• When atoms lose electrons they form a
positive ion
• When atoms gain electrons they form a
negative ion
#18 Adhesion
• An attraction between molecules of
different substances.
• Helps water stick to surfaces.
• Capillary action is when water moves
against the force of gravity. Like from the
roots to the top of a tree.
#19 Cohesion
• An attraction between molecules of the
same substance.
• Helps water stick to itself.
• This is why water beads on a smooth
surface.
#20 pH
• Measurement of H+ ions produced by
solutions when mixed with water.
• A compound that forms H+ ions in water is
an acid. Acids are found below 7 on the
pH scale.
• A compound that produces more OH- ions
in water is a base. Bases are found above
7 on the pH scale.
#21 Carbohydrate
• Contains carbon, hydrogen and oxygen.
• Main source of energy from food.
• Sugars and starches
#22 Protein
• Contains carbon, hydrogen, oxygen and
nitrogen (sometimes sulfur).
• Made of amino acids.
• Used for structure, organic catalysts and
gene expression.
#23 Enzyme
• A protein.
• Biological catalyst- speeds up chemical
reactions in the body.
#24 Nucleic Acid
• Store and transmit genetic information.
• DNA and RNA
• Made of nucleotides.
#25 Lipid
• Used for long-term energy storage,
protective coatings and insulation.
• Made of a glycerol and three fatty acids.
• Fats, oils and waxes.
#26 Monomer
• Subunit or building block of a larger
molecule.
• Many monomers bonded together make a
polymer.
• Polymers are large molecules.
#27 Monosaccharide
• Monomer of carbohydrates.
• Simple sugar.
• Glucose, fructose, galactose
#28 Amino acid
• Monomer of proteins.
• 20 different kinds
• The order of amino acids that goes in a
protein are encoded in DNA.
• Has an amino group (-NH2) and a
carboxyl group (-COOH).
#29 Nucleotide
• Monomer of nucleic acids.
• Made of a phosphate group, 5-carbon
sugar, and a nitrogen base.
# 30 Cell Theory
• All living things are made of cells
• The cell is the basic unit of life
• All cells come from preexisting cells
#31 Prokaryote
• Cells that do not contain a nucleus or
membrane-bound organelles.
• DNA floats in cytoplasm.
• May contain a cell wall.
• Ex. Bacteria
#32 Eukaryote
• Cells that contain a nucleus and membranebound organelles.
• Animal and plant cells.
#33 Cell Membrane
• Outer boundary of the cell, which regulates what
enters and exits the cell.
• Selectively permeable.
• Made of phospholipids and proteins.
• “Fluid Mosaic”
#34 Ribosome
• Site of protein synthesis (translation).
• Spherical body found floating in the
cytoplasm or attached to endoplasmic
reticulum.
• Made of rRNA and proteins.
#35 Cytoplasm/Cytosol
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Fluid matrix inside the cell
Many chemical reactions take place here.
Organelles float in the cytoplasm.
Made mostly of water
#36 Nucleus
• Controls the activities of the cell
• Contains the hereditary information of the
cell (DNA)
• Surrounded by the nuclear envelope
• Contains the nucleolus which makes
ribosomes
#37 Endoplasmic Reticulum
• Set of tubular
passageways involved
with the transport of
molecules in the cell.
• Smooth ER- no
ribosomes; transports
lipids
• Rough ER- ribosomes
attached; transports
proteins
#38 Mitochondria
• The organelle that
releases energy from
stored food
molecules.
• Site of cellular
respiration.
• Highly folded
membranes to
increase surface
area.
#39 Golgi Apparatus
• Stack of flattened membranes that processes
and packages proteins to be secreted out of the
cell
#40 Chloroplast
• Site of photosynthesis in the plant cell.
• Houses chlorophyll.
• Made of stacks of thylakoids called grana
and inner space called stroma.
#41 Lysosome
• Small organelles filled with enzymes
• Breaks down particles for the cell to use
#42 Cytoskeleton
• Network of protein filaments that help the
cell maintain its shape
• Made of microtubules (hollow) and
microfilaments (rods)
#43 Vacuole
• Saclike structures used by the cell to store
water, salts, proteins, and carbohydrates
• Large central vacuole in the plant cells
• Small or not present in animal cells
#44 Centriole
• Only in animal cells
• Involved in cell division
• Make the spindle that pulls chromosomes
apart
#45 Cilia & Flagella
• Used in cell movement
• Cilia- hairlike projection, numerous
• Flagella- taillike structures, 1-3
#46 Vesicle
• Transport containers for the cell.
• Made from the Golgi Apparatus and the
cell membrane.
#47 Passive Transport
• Movement of particles across cell
membranes by moving with the
concentration gradient.
• Diffusion or osmosis.
• Uses no energy.
#48 Diffusion
• Net, random movement of particles from
an area of higher concentration to an area
of lower concentration.
• Eventually results in even distribution.
#49 Osmosis
• Diffusion of water across a selectively
permeable membrane.
• Depends on the concentration of solutes
on either side of the membrane.
#50 Osmotic Solutions
• Hypotonic solutions- Solutions that have a
lower concentration of solute than the solution
inside the cell. This causes water to move into
the cell and the cell will swell.
• Hypertonic solutions- Solutions that have a
higher concentration of solute than the solution
inside the cell. This causes water to move out of
the cell and the cell will shrink.
• Isotonic solutions- The solutions inside and
outside the cell have the same concentration of
solute. The cell does not change shape.
#51 Active Transport
• Process by which cells transport materials
across the cell membrane against a
concentration gradient.
• Uses energy.
#52 Endocytosis
• Process of taking material into the cell by
means of vesicles.
• Pinocytosis- “cell drinking”
• Phagocytosis- “cell eating”
#53 Exocytosis
• The removal of large particles from the
cell.
• Vesicles fuse with the cell membrane and
force contents out of the cell.
#54 ATP
• Adenosine
triphosphate
• Stored cellular
energy
• Made from
adding a
phosphate to
ADP.
#55 Photosynthesis
• Process by which plants use light energy to
convert water and carbon dioxide into glucose
and oxygen.
• Happens in the chloroplast.
6CO2 + 6H2O + light  C6H12O6 + 6O2
Carbon+water+sunlightGlucose+oxygen
Dioxide
#56 Cellular Respiration
• Breaking down of glucose into usable
energy (ATP).
• Aerobic
• Happens in mitochondria.
C6H12O6 + 6O2  6H2O + 6CO2 + 36
ATP
Glucose +Oxygen Water + Carbon + Energy
dioxide
#57 Aerobic
• Reaction that requires oxygen.
• Cellular respiration
#58 Anaerobic
• Reaction that does not require oxygen.
• Fermentation
#59 Fermentation
• Anaerobic breakdown of organic
substances.
• Alcoholic- gives of alcohol & carbon
dioxide
• Lactic acid- gives off lactic acid.
#60 Cell Cycle
A. G1
B. S
M phase
C. G2
D. Metaphase
#61 Chromosome
• Compact form of DNA
and protein in the
nucleus of a cell
about to divide.
• Come in homologous
pairs in diploid cells.
Centromere
Sister Chromatids
#62 Chromatin
• Genetic material that is found in the
nucleus of a nondividing cell.
• Unwound, stringy form of DNA.
#63 Mitosis
• Cell division in which two daughter cells
are produced, each containing a complete
set of chromosomes.
• Done by somatic cells.
• Diploid cell division.
• Prophase, metaphase, anaphase,
telophase.
#64 Cytokinesis
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Division of the cytoplasm.
Happens at the end of cell division.
Animal cells- pinch inwards; cleavage
Plant cells- form cell plate down center of
cell
#65 Gamete
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Sex cells
Female- egg cell; Male- sperm
Haploid
Made during meiosis
#66 Haploid
• Cell with one of each type of chromosome.
• n
• Sex cells
#67 Diploid
• Cell with two of each type of chromosome.
• 2n
• Somatic cells.
#68 Meiosis
• Type of cell division in which a body cell
produces four sex cells (gametes).
• Each gamete contains half the number of
chromosomes as the original cell.
• All four cells produced are genetically
different.
#69 Crossing Over
• When chromosomes pair up and
exchange parts of their chromatids.
• This creates genetic variations.
• Happens during prophase I.
#70 DNA
• Deoxyribonucleic acid.
• Double stranded, has thymine, has
deoxyribose sugar in its nucleotides.
• Stores genetic information for all living
organisms.
#71 RNA
• Ribonucleic acid.
• Three forms: mRNA, tRNA, rRNA
• Single stranded, has uracil instead of
thymine, has ribose sugar in its
nucleotides.
#72 Replication
• Process that makes two copies of DNA.
• Happens during the S phase of
interphase.
#73 Translation
• Process that uses information on a strand
of mRNA to make a protein.
• Done at the ribosomes.
#74 Transcription
• Process that makes RNA from DNA.
• Takes place in the nucleus.
• Makes mRNA.
#75 Mutation
• Changes in a DNA sequence that affects
genetic information.
• Chromosome mutations- nondisjunction,
translocation, inversion, deletion,
insertion/duplication
• Gene mutations-point, frameshift
#76 Gene
• Small segment of DNA that controls a trait.
#77 Allele
• The different forms of a gene.
• Represented by letters in genetics. Ex. Aa,
BB, tt
#78 Dominant & Recessive
• Dominant alleles will always show up over
recessive alleles if both are present.
• Dominant represented by capital letter.
• Recessive represented by lower case
letter.
• Only express recessive trait if all alleles
present are recessive.
#79 Heterozygous
• The presence of two different alleles for a
trait.
• Bb
• Carrier of a trait.
• Hybrid
#80 Homozygous
• The presence of two identical alleles.
• GG
• Purebred
#81 Genotype
• The combination of genes/alleles in an
organism.
• Whether they are homozygous or
heterozygous.
• Ex: BB, pp, Rr
#82 Phenotype
• Outward appearance of an organism
regardless of its genes.
• Physical expression of a trait.
• The way an organism looks.
#83 Inheritance Patterns #1
• Incomplete dominance- neither allele is
dominant over the other; heterozygous is a
mix
• Codominance- both alleles are dominant;
the heterozygous shows both traits
• Multiple alleles- gene controlled by more
than just two alleles
#84 Inheritance Patterns #2
• Sex linked-genes that are located on the
sex chromosomes; usually passed from
mother to son
• Polygenic- traits controlled by multiple
genes; many different phenotypes
#85 Genetic Technology
• DNA fingerprinting- Using gel
electrophoresis to compare DNA strands
from different organisms
• Cloning- making genetically identical
copies
• Transgenic Organisms- implanting genes
from another organism
#86 Karyotype
• A picture of chromosomes arranged with
their homologous pairs in order from
largest to smallest.
• 1-22 are autosomes
• 23- sex chromosomes
#87 Pedigree
• Chart that shows the relationship within a
family.
• Can be used to show how a gene is
passed from one generation to the next.
• Males• Females-
#88 Spontaneous Generation
• Or abiogenesis.
• The idea that living things can come from
nonliving material.
• Disproved.
#89 Endosymbiosis
• Relationship in which one organism lives
within the body of another
• Both benefit from the relationship
• Ex- bacteria in human intestines
#90 Fossil
• Preserved remains or evidence of a past
organism
#91 Evolution
• The change in a population over time.
• The gathering of adaptations to make a
species “better.”
• Not a proven theory, but is widely
accepted.
#92 Vestigial Structure
• Structures that are
present in organisms,
but are functionless.
• Indicate change in an
organism.
• Example: femur (leg
bone) in whales and
snakes; appendix or
coccyx in humans
#93 Homologous Structure
• Structures that are similar in arrangement
and functions, but modified for specific
organisms.
• Example: Human arm, whale flipper, bat
wing (all have the same type of bones and
functions, but look different)
#94 Adaptation
• Characteristic that allows an organism to
survive better in its environment. It gives
the organism an advantage.
• Example: Cacti have thorns instead of
leaves to prevent water loss.
• Example: Camouflage helps tigers blend
into their surroundings so they can hunt
prey.
#95 Fitness
• The ability of an organism to survive and
reproduce in its environment.
• The strongest, smartest, cleanest
individuals are the most fit because that
can survive the longest.
#96 Gene Pool
• All the different genes that are in one
population.
• Depends on how large the population is to
how diverse the genes are.
#97 Natural Selection
• “Survival of the Fittest”
• Process by which individuals that are
better suited to their environment survive
and reproduce most successfully.
• Directional- Disruptive- Stabilizing-
#98 Taxonomy
• The science of identifying, naming and
classifying organisms based on their
characteristics.
• 7 different levels- Kingdom, phylum, class,
order, family, genus, species
#99 Kingdom
• Taxonomic group of similar phyla or
divisions.
• Animalia, Plantae, Fungi, Protista,
Eubacteria, Archaebacteria
#100 Phylum
• Taxonomic group of similar classes.
#101 Class
• Taxonomic group of similar orders.
#102 Order
• Taxonomic group of similar families.
#103 Family
• Taxonomic group of similar genera.
#104 Genus
• Firs word of a two-part scientific name
used to identify a group of similar species.
• Always capitalized.
• Example: Panthera leo; Panthera= genus
#105 Species
• Group of organisms that can interbreed and
produce fertile offspring.
• Second word of a two-part scientific name.
• Not capitalized.
• Example: Mus musculus; musculus= species
#106 Vertebrate
• An animal with a backbone.
• Examples: humans, dog, snake
#107 Invertebrate
• An animal that does not have a backbone.
• Example: jellyfish, insects
#108 Amphibian
• Organisms that develop from aquatic
larvae into air breathing, semi-terrestrial
adults.
• Example: Frogs, salamanders
#109 Mammal
• Animal characterized by having warmblood, a backbone, nourishing young with
milk secreted by mammary glands, and
hair on the skin.
• Examples: Humans, whales, bears
#110 Reptile
• Animal that is completely adapted to life
on land. Characterized by scaly skin,
claws, and a more developed skeletal
system than amphibians.
• Ectothermic or “cold-blooded”
• Examples: snakes, crocodiles, turtles
#111 Vascular plant
• Plant that contains vascular tissue (xylem
& phloem)
• Xylem transports water
• Phloem transports food
• These can be taller
#112 Nonvascular plant
• Does not contain vascular tissue
• Short growing plants such as mosses,
liverworts, and hornworts.
#113 Angiosperm
• Flowering plants
• Monocots and dicots
#114 Gymnosperm
• Plant that produces seeds in cones
• Pines, firs
#115 Biosphere
• Part of the earth where life exists.
• Ranges from deep into the earth’s crust to
up in the atmosphere.
#116 Climate
• Overall weather conditions in an area that
include temperature and precipitation.
#117 Biogeochemical Cycle
• Cycle of important elements and
compounds through the living and
nonliving parts of the ecosystem.
• Water cycle, nitrogen cycle, and carbonoxygen cycle, phosphorus cycle
#118 Trophic Level
• Every step in a food chain or food web.
• 1st trophic level is always a producer.
#119 Biome
• Regions of Earth with characteristic types
of plants and animals.
• Tundra, Taiga, Temperate Forest, Tropical
Rain Forest, Grassland, Desert
#120 Niche
• The role an organism has in its
ecosystem.
• Includes feeding and mating habits.
#121 Commensalism
• Symbiotic relationship in which one
organism benefits and the other is neither
helped nor harmed.
• +, 0
• Ex. Whales and barnacles
#122 Parasitism
• Symbiotic relationship in which one
organism benefits and the other is
harmed.
• +, • Ex. Tick and dog, tapeworm and human
#123 Mutualism
• Symbiotic relationship in which both
organisms are benefitted.
• +,+
• Ex. Lichen, bees and flowers
#124 Habitat
• The place where an organism lives, finds
food and water, mates and is able to
survive and reproduce.
#125 Carrying Capacity
• The largest number of one species that an
environment can support.
#126 Succession
• Series of predictable changes in an
ecosystem.
• Primary- starts with no soil
• Secondary- starts with established soil
• Starts with pioneer species.
#127 Introduced Species
• Species that are introduced to an area that
they are not normally found.
• Disrupts the natural food web and flow of
the ecosystem.
• Ex. Kudzu, zebra mussels
#128 Biodiversity
• The total amount of different species living
in an area.
• Highest in tropical regions.
#129 Limiting Factor
• Factors that limit how large a population
can grow or where something can live.
• Temperature, amount of food, etc.
#130 Bacteria
• Unicellular, prokaryotes
• Archaebacteria (extreme bacteria) or
Eubacteria (common bacteria)
• Coccus
• Bacillus
• Spirillum
#131 Virus
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Nonliving, but life-like
Retrovirus-has RNA instead of DNA
Bacteriophage- virus that infects bacteria
Lysogenic Cycle- virus is “asleep” in host
Lytic Cycle- virus is active in host, kills the
host cell