Download Biology Quick Notes

Biology Quick Notes
Safety
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If one of your answer choices is “tell your instructor or teacher,” that is the RIGHT answer…. ALWAYS!
Use common sense. Don’t run, be careful with glass and sharp tools, don’t let clothing and hair hang into a
fire, etc.
Always wear goggles!!
Never put hot glass into cold water. It will break/explode!!
Never heat a sealed flask. The pressure will cause the cork and fluid to shoot out!
Lab Equipment
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Length=meter stick-meters (m, cm, or mm)
Mass=triple beam balance-grams (g or kg)
Volume=beaker, flask, graduated cylinder-liters (L or mL)
Temperature=thermometer-(oC)
Looking at something small? Choose a microscope!
Experimental Design
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Steps of an experiment:
o Problem
o Hypothesis
o Experiment
o Analysis
o Conclusion
Problem=question
Hypothesis=educated guess
o IF…. THEN statement
o More specifically, IF… independent variable, THEN…. dependent variable.
Experiment
o Independent variable= what changes; look for the word “different”
o Dependent varible= what is measured; look for collection of data
o Control=compare to experimental data to make it more accurate
 Try putting the word NO in front of your independent variable
 Ex: IV=fertilizer Control=No fertilizer
o Constants=things that you keep the same
Analysis
o QuaLitative Data= letters, quality
o QuaNtitative Data= numbers, quantity
Conclusion
o Summary of findings, restate hypothesis
Graphing
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Independent Variable on X axis (horizontal); Dependent Variable on Y axis (vertical)
Types of graphs
o Line graph- shows change over time
o Bar graph- compares similar but separate categories
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o Circle/Pie graph- parts of a whole (percentages!)
If there is a chart, graph, or table, you will need to use it to answer the question. They don’t waste space
for no reason!
Look for patterns in the graphs; ex. add 10, double, etc.
Organization
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Cell-basic unit of life
Cell, Tissue, Organ, Organ System, Organism, Population, Community, Ecosystem, Biosphere
A bunch of identical cells =tissue
A bunch of different types of cells =organ
Populations
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Biotic factors=anything living
Abiotic factors=anything nonliving
Niche=organism’s job or role in ecosystem
o If two animals share the same niche, competition will result
o Organisms will compete until one dies or adapts to a new niche
Predator vs. Prey
o Predator= eats the prey
o Prey= gets eaten by predator
o Predator increases, prey dies---- Predator decreases, prey reproduces
Types of Curves
o J-curve= Exponential graph; Ideal conditions with unlimited resources and no predators
o S-curve= Realistic graph; Actual conditions in environment
Carrying Capacity
o Point where S-curve levels off or flattens or when it begins to fluctuate at an even rate
o Carrying capacity is number of a species that can be supported by the environment
o If population exceeds carrying capacity, it will decrease until it is below carrying capacity
Ways to predict graphs
o Increase in predators=population decreases
o Increased birth rate=population increases
o Increased death rate=population decreases
o Environment restoration=population increases
Symbiosis
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Symbiosis-relationship between organisms of different species
Parasitism- one benefits and the other is harmed (+/-)
Mutualism- both benefit (+/+)
Commensalism- one benefits and the other is not harmed or benefitted (+/o)
Competition-organisms of the same species challenging each other for resources or an environmental
niche (job)
Food Chains/Webs/Pyramids
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Producer-Makes their own energy/food (Plants)
Consumer-Has to eat something to get food/energy (Animals)
Herbivore- Eats plants
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Carnivore- Eats meat or other animals
Omnivore- Eats both plants and meat
Decomposers-Eat dead stuff
Food Chain- A simple line of who eats whom (usually only 3 to 4 links)
 EX: grass  grasshopper  frog snake
Arrows always point to the one GETTING the energy (eating)!!
Food Web- A bunch of related food chains (can be very complex!!)
Food Pyramids- Show how energy is transferred between trophic levels
 Energy moves UP the pyramid, never DOWN
Trophic level- each feeding level of the pyramid
 Producers—Produce their own food (ex. plants)
 Primary Consumers or 1st Order Heterotrophs—Eat producers (ex. Mouse)
 Secondary Consumers or 2nd Order Heterotrophs—Eat primary consumers (ex. Snake)
 Tertiary Consumers or 3rd Order Heterotrophs—Eat secondary consumers (ex. Hawk)
Rule of 10: Only 10% of the energy moves UP each trophic level. 90% is lost to the environment.
Biomass—How much dry weight exists at each level
 The lowest level on the pyramid has the biggest biomass, because it is is the biggest level. The
highest level has the least biomass.
 Subtract a 0 from the number of calories for each trophic level you move up. Add a 0 if you are
moving down the pyramid
Cycles
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Water Cycle—Water moving through the environment
o Condensation- Water goes from gas to liquid in clouds
o Precipitation- Water falls from the sky
o Lakes, Rivers Streams, Groundwater, Oceans
o Evaporation-Water goes from liquid to gas back into the sky
o Transpiration- Water leaves plants as a gas
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Carbon Cycle—Carbon and oxygen cycling through the environment
o Plants take in CO2 and release O2 (Photosynthesis)
o Animals take in O2 and release CO2
o Dead animals become fossils fuels underground after millions of years
o Burning (wood, gas, or factories) releases carbon into the atmosphere
Nitrogen Cycle—Nitrogen cycling through environment
o Key Player—BACTERIA!!!
o Nitrogen exists as a diatom, N2, in the atmosphere
o Nitrogen is converted by soil microbes (bacteria) into nitrates and nitrites for plants to use
o We get our nitrogen by eating plants
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Biochemistry
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Water- Liquid required for life
o Cohesion- Water sticks to itself
o Adhesion- Water sticks to other stuff
o Surface Tension- light things can stand on it; water makes a “bubble” instead of instantly
spilling over
o Heat Capacity- You can heat it a lot before it boils
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Biochemicals- Chemicals that make up living things—all contain Carbon
o Carbohydrates- simple and complex sugars; quickest energy source
o Lipids- fats; store energy; make up cell membrane
o Proteins- make up muscles; also carry out cell functions
o Nucleic Acids- make up DNA and RNA
Cells
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Basic unit of life
All living things have DNA
Prokaryotes
o Bacteria
o Have NO nucleus or membrane bound organelles
o Usually have cell wall, cell membrane, cytoplasm, DNA, and ribosomes
Eukaryotes
o Plants and Animals
o Have a nucleus and lots of membrane bound organelles
o All have mitochondria
Animal Cells
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Cell Membrane- goes around cell
Cytoplasm-Jelly-like fluid inside cell
Nucleus- holds DNA
Mitochondria- Cellular Respiration; make ATP (cell energy)
Ribosomes- Make proteins aka protein synthesis
Plant Cells
o Have all the same organelles as animal cells plus some extras
o Cell Wall-Provides additional structure to cells; outside of cell membrane; reason why
plants can’t move
o Chloroplasts- Photosynthesis; make sugar; make plant green
o Large Vacuole- stores large amounts of water and nutrients in plants
Plasma Membrane
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Protects cells and acts as a boundary between what’s inside and outside the cell
Phospholipid Bilayer- two layers of phospholipids
o Hydrophilic Head- likes water (point out toward water in/out of cell)
o Hydrophobic Head- hates water (point toward each other)
Diffusion- small molecules moving across plasma membrane from area of high concentration to low
o Remember Febreeze activity and being stuck in the corner of the room and then spreading
out
o Osmosis- diffusion of water
When small molecules cannot diffuse, they can use membrane proteins to help
o Channel Proteins- move water across membrane when there are large amounts of water to
move; does not use energy
o Carrier Proteins- molecules bind to protein and are moved across the membrane; use
energy
When molecules are too big….
o Endocytosis- engulfing large molecules; bringing them into the cell
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 Pinocytosis-engulfing liquids
 Phagocytosis- engulfing solids
o Exocytosis-“throwing up” molecules; taking them out of the cell
Passive Transport
o No energy needed
o Moves high to low
o Diffusion, Osmosis, Channel Proteins
Active Transport
o Uses energy
o Moves from low to high
o Carrier Proteins, Endocytosis, Exocytosis
Osmosis
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Special word for water diffusing across the plasma membrane
Water moves from area of high concentration to low concentration
Easiest way to remember how water moves… After you drink something salty, you want water… Water
will move to wherever it’s saltier
Isotonic- Water concentration same inside and outside of cell; water will move in and out at equal rates
Hypertonic- Water concentration is higher in cell; Water will move out of cell
Hypotonic- Water concentration is higher outside of cell; Water will move into cell
Photosynthesis and Cellular Respiration
Photosynthesis
o Occurs in chloroplasts of plant cells
o Makes food (glucose) for plants
o Happens during the day, because sun is needed
o 6H2O+ 6CO2+ sunlight  C6H12O6 (glucose) + 6O2
o Needs carbon dioxide (CO2), makes oxygen (O2)
Cellular Respiration
o Occurs in mitochondria of both plant and animal cells
o Makes ATP (cell energy)
o Happens anytime—day or night
o C6H12O6 (glucose) + 6O26H2O+ 6CO2+ ATP
o Needs oxygen (O2), makes carbon dioxide (CO2)
Mitosis & Meiosis
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Mitosis-body cells reproduce; asexual reproduction
o PMAT
o Prophase- chromatin condenses into chromosomes; nuclear membrane breaks down
o Metaphase- chromosomes line up along equator
o Anaphase- chromosomes pulled to opposite end of the cell
o Telophase- chromosomes begin to unravel; nuclear membranes reform
o Cytokinsesis- cell pinches apart
o Start with 46 chromosomes in 1 cell= end with two cells each with 46 chromosomes
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Meiosis-sex cells reproduce; sexual reproduction
o PMAT
o Prophase I- chromatin condenses into chromosomes; nuclear membrane breaks down;
homologous chromosomes find their match
o Metaphase I- homologous chromosomes line up across from each other along equator
o Anaphase I- each homologous chromosome pulled to opposite ends of the cell (don’t split
in half this time; whole X moves to one side or the other)
o Telophase I- first cell pinches into two; process begins again with two cells
o Prophase II, Metaphase II, Anaphase II, Telophase II- just like PMAT in mitosis except
happening in two cells instead of just one
o Cytokinsesis- cell pinches apart
o Start with 46 chromosomes in 1 cell= end with four cells each with 23 chromosomes
(HALF)
DNA v. RNA
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DNA is found in all living things
DNA is the blueprint for life
DNA and RNA made up of nucleic acids
Nucleotide- basic unit of DNA and RNA
o Contain sugar, phosphate group, and nitrogen base
o DNA has sugar called deoxyribose
o RNA has sugar called ribose
Nitrogen bases on each strand of DNA/RNA pair up with a complementary base on the other strand
o DNA- A=T
C=G
o RNA- A=U
C=G
DNA is in the form of a twisted ladder aka DOUBLE HELIX
RNA is single stranded
Transcription- DNA is copied into mRNA
Translation- mRNA is copied into tRNA
o tRNA is attached to amino acid
o amino acids make a chain… a chain of amino acids make a protein
Mutations in DNA cause genetic variations
o Mutations can be a adding letters, subtracting letters, switching letters, or reversing entire
sections
Genetics
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Gregor Mendel- Father of Genetics
o Discovered how genes are passed down to offspring by studying peas
Dominant trait masks recessive trait
To have a recessive trait, you must have a recessive allele from BOTH parents (bb)
Homozygous- same allele from each parent (BB or bb)
Heterozygous- different allele from each parent (Bb)
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Use Punnett square to determine odds of offspring
B
b
BB
Bb
B
Genotype: BB, Bb, bb
Ratio: 1:2:1
bb
b Bb
Phenotype: Brown, Blue
Ratio: 3:1
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Incomplete Dominance: traits blend together, because neither is dominant
o Ex. flower color
Codominance: both traits show up, because both are dominant
o Ex. Cow spots, calico cats, blood type
Sex-Linked Traits: traits that are carried on the X or Y chromosomes
o Sex-linked traits are almost always on the X chromosome
o More common in males, because they only need one allele instead of two (XY vs XX)
o Examples: XHXH XHXh XhXh XHY XhY
o If a female is heterozygous, she is called a carrier (XHXh)
Pedigrees- family charts that help you tell how a certain trait is carried through the generations
o Square-male
Circle-female
o Dark- affected
Light-unaffected
o Square and circle connected horizontally-married
o Vertical lines-children
o Each row is a generation
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Evolution and Natural Selection
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Evolution-change over time (usually a VERY LONG time)
Natural Selection- how evolution happens
o Mutations occur
o If the mutation is helpful, then that organism with survive and carry on the gene to the next
generation
o Over time, the population will shift and have more organisms with that mutation
Phenotype Distribution graphs
o Stabilizing- same bell curve but skinnier; selects for average
o Directional- graph shifts to one side or the other; selects for one extreme or the other
o Disruptive- graph flips upside down; selects for extremes and against middle or average
Speciation- making of new species
Best way to tell if species are related is by looking at DNA
If DNA is not available, look at fossils or bone structure
Homologous structures- structures that evolved from a common ancestor (bones)
Analogous structures- same function but evolved separately (wings)
Classification
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Ways of grouping organisms based on evolutionary similarities
Kingdom, Phylum, Class, Order, Family, Genus, Species
o Kingdoms: Archaebacteria, Eubacteria, Protista, Fungi, Plantae, Animalia
Binominal Nomenclature- scientific name; use the organisms genus and species
Fan diagram- closer on chart means more closely related
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Cladogram- shows relationships between species based on common features
o The ones closest to the beginning (left) are the common ancestors to the ones toward the
right
o If one part branches, those species are the most related
Dichotomous Key- use key to determine classification of an unknown organism
Behavior
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Innate- A behavior that is inherited from your parents
o Ex. fight or flight, instincts, courtship
Learned- A behavior that is learned through practice after birth
o Imprinting- organism creates a socially attachment quickly after birth and follows it around
to learn behaviors for survival
 Mendel! 
o Trial and Error- organism is rewarded for a certain behavior
 Making a nest
o Conditioning- learning to respond to something by association
 Pavlov’s dogs
o Insight- use previous experiences to respond to new situation
 Doing math problems