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Honors Biology: Final Exam Review
Honors Biology: Final Exam Review
Quarter #1
Chapter 1: The Scientififc Study of Life
Tools for Studying LifeMicroscope – observe living cells
Compound Microscope – uses multiple lenses to magnify an image
Electron Microscope – uses a beam of electrons to create high quality, high magnification images
Balance – take mass of objectsMeter Stick – measure length of an objectGraduated Cylinder – measure volume of
a liquid
Chapter 1: The Scientifc Study of Life
8 Characteristics of Living Things:1. made up of cells (smallest unit of life)2. reproduce (sexually or aesexually)3. based on universal genetic code (DNA)4. grow & develop5. obtain & use materials/energy
(metabolism)6. respond to their environment (stimuli)7. maintain stable internal environment
(homeostasis)8. change over time (evolution)
Chapter 1: The Scientififc Study of Life
Organization in Biology Ecosystem – group of organisms that live in the same place
together with their non-living environment Community – group of many populations that live in the same
general area Population – group of organisms of the same species that live in
the same general area Organism – individual life form Organ System – group of organs that work together to complete
a common task Organ – a group of tissues that work together to complete a
common task Tissue – a group of cells that work together to complete a
common task Cell – the smallest unit of life Molecule – a group of elements that are
Darwin & EvolutionCharles Darwin
Struggle for Existence – organisms compete against each other for necessary resources
Survival of the Fittest – those individuals best fit for their environment secure resources and surviveAdaptations – features or characteristics that
increase an organisms chance of survivalNatural Selection – Organisms with
beneficial adaptations survive and pass on beneficial traits to offspring
Darwin & Evolution
Factors Leading to EvolutionMembers of the same species
become separated from one another and develop independently (speciation)
Change in Environmental Factors – due to natural or unnatural causes
Migration of organisms to a new environment (natural or unnatural)
Chapter 2: The Chemical Basis of Life
Types of Chemical Bonds:Ionic Bonds – attractions between ions of
opposite charge; involve one atom donating an electron to another atom
Covalent Bond – the sharing of pairs of electrons to join molecules together (single, double, triple)
Hydrogen Bonds – weak bonds formed by the slightly charge regions on neighboring molecules; responsible for H2O’s unique properties
Chapter 2: The Chemical Basis of Life
Properties of Water (thanks to polarity)Cohesion – the slight - charge of O attracts the slight
+ charge of H causing neighboring molecules to “stick” together (H bonds)
Adhesion– the slight charges of H2O molecules make it likely to “stick” to other things
Moderate Temperature – H bonds help H2O resist changes in temperature (HIGH boiling point)
Density – liquidH2O is MORE dense than solid H2OSolvent – polarity helps H2O to break down other
POLAR substances (non-polar substances like oils WILL NOT dissolve in H2O)
Quarter #2
Chapter 3: The Molecules of Cells
The Magic of CarbonBecause of its 4 valence electrons,
carbon:has a tendency to form covalent bonds is able to make single, double, or triple
bonds is able to form VERY LONG chains is able to bond with up to 4 other atoms
Macromolecules – large chain molecules (polymers) formed by subunits (monomers)
Chapter 3: The Molecules of Cells
4 Main Organic (Carbon) Compounds:Carbohydrates (polysaccharides)
Main source of energyMade up of monosaccharides
(sugars)***Isomers – two molecules that has the SAME chemical formula, but DIFFERENT structures!
Chapter 3: The Molecules of Cells
4 Main Organic (Carbon) Compounds:Proteins
Control reaction rates, allow molecules in and out of cells, fight disease, make up muscles
Made up of amino acids• 20 + amino acids are used to express genes•each amino acid in a polypeptide chain is joined to by a peptide bond
Chapter 3: The Molecules of Cells
4 Main Organic (Carbon) Compounds:Lipids
Comprise membranes, energy storage, insulation
Made up of glycerol & fatty acids• Phospholipids make
up bilayer of cell membrane
Chapter 3: The Molecules of Cells
4 Main Organic (Carbon) Compounds:Nucleic Acids
Store and transmit genetic information
Made up of nucleotides (sugar, phosphate group & nitrogenous base)
• 5 Nitrogenous Bases:• Adenine (DNA & RNA)• Thymine (DNA ONLY)• Guanine (DNA & RNA)• Cytosine (DNA & RNA)• Uracil ( RNA ONLY)
Chapter 3: The Molecules of Cells
Dehydration Synthesis – joining of two or more organic molecules by REMOVING H2Oone molecule loses a hydroxyl (-OH); one loses
a hydronium (-H)covalent bonds form (sharing e-)
Hydrolysis – breaking apart of two or more organic molecules by ADDING H2Oone molecule gains a hydorxyl (-OH); one
gains a hydronium (-H)covalent bonds are broken
Early EarthStanley Miller & Howard Urey
showed that amino acids & other organic componds could have arisen from a lifeless Earth (chemical soup + lightening)
Evolution of oxygen-producing bacteria resulted in:oxygenation of the atmospheremassive extinction of many early anaerobic forms of
lifeextincting of bacteria unable to tolerate oxygenanarobic bacteria engulfing aerobic bacteria for
survival (endosymbiotic theory)
Chapter 4: A Tour of the Cell
Types of CellsProkaryotes – lack a “true” nucleus; lack
membrane-bound organelles; bacteriaEukaryotes – have a “true” nucleus; have
specialized membrane-bound organellesPlant Cells – contain cell walls, large vacuoles;
chloroplasts; square-ish in shapeAnimal Cells – contain only a cell membrane;
contain centrioles; irregular in shape
Chapter 4: A Tour of the Cell
Plasma Membrane – “proteins floating in a sea of lipids”Phsopholipid Bilayer – primary component;
made up of glycerol, phosphate group (polar & hydrophilic), and 2 fatty acid tails (non-polar & hydrophobic); arranged with tails facing the interior & heads facing exterior
Chapter 4: A Tour of the Cekk
Receptor Proteins – receive messages from outside the cell
Anchor Proteins – inside of membrane; aid in tethering organelles
Transport Proteins – transmembrane proteins that serves as passageways for larger molecules
Cholesterol – within bilayer; prevent solidifying of fatty acid tails
Glycoproteins & Glycolipids – used for identification
Chapter 4: A Tour of the Cell
Fluidity of the Phospholipid BilayerALL components of the bilayer are able to move
freely about one another; this is because:phosphoipids are unable to pack closely togetherkinks in the fatty acid chains allow for movement fatty acid chains are typically unsaturated (not
solid at room temperature)cholesterol prevents fatty acid tails from “sticking”
Permeability – ability to allow some molecules to pass through while blocking others (phenylthalanine & ammonia)
Chapter 4: A Tour of the Cell
Cellular TransportDiffusion – “passive transport;” no ATP
required; random movement of molecules from an area of HIGH concentration to an area of LOW concentration Osmosis – diffusion of water from an area of HIGH
H2O concentration to an area of LOW H2O concentration (osmoregulation – regulation of H2O inside a cell)
Active Transport – use of ATP energy to molecule molecules (or maintain molecules) AGAINST a concentration gradient
Chapter 4: A Tour of the Cell
40 % Sucrose60 % H2O
20 % Sucrose80 % H2O
• Outside environment is HYPERTONIC (less H2O; more sucrose) to inside•Inside environment is HYPOTONIC (more H2O; less sucrose) to outside
•THEREFORE H2O will LEAVE the cellISOTONIC solutions – have equal concentrations of both SOLUTES and H2O
Chapter 4: A Tour of the Cell
•In order to effectively transport nutrients to the cell, the cell must have a LARGE surface area to volume ratio
Chapter 4: A Tour of the Cell
Organelles of the CellMitochondria – “powerhouse;” responsible
for Cellular Respiration; resemble early prokaryotes; have their own DNA; reproduce independently; incorporated by heterotrophic prokaryotes
Chloroplast – responsible for Photosynthesis; resemble early prokaryotes; have their own DNA; reproduce independently; incorporated by heterotrophic prokaryotes
Chapter 4: A Tour of the Cell
Organelles of the CellGolgi Apparatus – modifies, sorts, and
distributes proteinsNucleus – controls all activity of the cellEndoplasmic Reticulum – allows for
intracellular transportRibosome – site of protein synthesisCytoplasm – cellular matrix
Chapter 5: The Working Cell
Enzymes – biological catalysts that speed up chemical reactions by lowering activation energyEnzymes are recyclable – they are not used up
or altered and can be used over and overEnzymes are VERY specific – each enzyme only
does ONE job; 3D structure determines its functionEnzymes have ideal temperatures and pHs -
if an an enzyme’s environment changes, it will become denatured (change shape) and not be able to function
Chapter 5: The Working Cell
Exergonic Reactions – Products contain less energy than reactants; proceed spontaneously; release energy (heat)
Endergonic Reactions – Products contain more energy than reactants; DO NOT proceed spontaneously; absorb energy (heat)*
* feel cold to the touch
Exergonic and Endergonic reactions are usually coupled… the energy released from exergonic reactions can be used to power endergonic reactions!
Chapter 5: The Working Cell
Oxidation-Reduction (Redox) ReactionsLEO says GER
LOSE electrons OXIDATIONGAIN electrons REDUCTION
Quarter #3
Chapter 6: How Cells Harvest Chemical
EnergyCellular Respiration – the process by which
energy is obtained from organic compounds (mitochondria)ATP is produced by the joining of ADP molecules
with inorganic phosphates C6H12O6 + 6O2 6CO2 + 6H2O + ATP Energy
Lipids contain the MOST energy/gram, but our bodies do not readily break down these molecules
Carbohydrates contain the next highest amount of energy/gram and our bodies can readily break them down
Chapter 6: How Cells Harvest Chemical
EnergyStep 1: Glycolysis (anaerobic)
A glucose molecule (C6H12O6) is broken down to create 2 molecules of Pyruvic Acid
Step 2: Kreb’s Cycle (aerobic)Pyruvic Acid is broken down to form CO2 waste
Step 3: Electron Transport (aerobic)High energy electrons are passed along a chain of
electron acceptors to produce a charge gradientChemiosmosis
The movement of protons through ATP Synthase powers the joining of ADP and P to make ATP
Chapter 6: How Cells Harvest Chemical
EnergyFermentation – an anaerobic form of
respiration employed by organisms in the absence of oxygen or by organisms unable to use/incorporate oxygen LESS efficient at producing ATP molecules
Glycolysis CAN still proceedEthyl Alcohol and/or Lactic Acid may form is
byproducts2 Net ATP will result from the process
Chapter 7: Photosynthesis: Using
Light to Make FoodLeaf Structure
Stoma (stomata) – openings in the leaf that allow gasses, such as O2 and CO2 to pass in and out
Mesophyll – layer of leaf tissue that contains chloroplasts
Chloroplast – organelle that contains photosynthetic pigments (chlorophyll) that REFLECT green light and absorb other colors (giving plants their
green color)
Chapter 7: Photosynthesis: Using
Light to Make FoodPhotosynthesis – the process by which
energy from the sun is converted into starches Organisms that make their own food in this
manner are called photosynthetic autotrophs6CO2 + 6H2O C6H12O6 + 6O2
Chloroplasts contain:Grana – stacks of disc-shaped thylakoid
membranes; site of Light-Dependant ReactionsStroma – fluid portion; site of Carbon Fixation
Chapter 7: Photosynthesis: Using
Light to Make FoodLight Dependant Reactions – H2O is broken
down (released waste O2 gas) and high energy electrons are passed down the Electron Transport Chain creating ATPEnd products: waste O2, & {ATP, NADPH, FADH2}
used to produce glucose during Carbon FIxationCarbon Fixation – occurs when carbon in the
form of CO2 is incorporated into organic storage moleculesEnd products: glucose
Chapter 8: Mitosis & Meiosis
Cell CycleInterphase
G1 – growth; normal functionS – synthesis; DNA is copiedG2 – additional growth; preparation for mitosis
Chapter 8: Mitosis & Meiosis
Cell CycleMitosis
Prophase – DNA condenses; nuclear envelope breaks down; centrioles form
Metaphase – Chromosomes line up along equator of the cell
Anaphase – Spindle fibers pull chromatids apartTelophase – nuclear division; 2 new nuclei formCytokinesis – cytoplasmic division; cell plate or
cleavage furrow form and split cells
Chapter 8: Mitosis & Meiosis
Regulation of Cell Growth:chromosomes DO NOT separate until spindle
is attached to each centromerecells are prevented from dividing unless they
are anchoredcells DO NOT grow in the absence of growth
factorsMitosis DOES NOT occur until DNA
Replication is complete
Chapter 8: Mitosis & Meiosis
Meiosisreductive cell division used to create
gametes (with ½ the genetic information of somatic cells)
create unique gametes due to:crossing over (exchange of segments of
genetic code by homologous chromosomes) random positioning of chromosomes during
Metaphase I random fertilization
Quarter #4
Chapter 9: Patterns of Inheritance
Gregor Mendel – father of geneticsHeterozygous – two different alleles for a traitHomozygous – two IDENTICAL alleles for a traitDominant – trait will be phenotypically expressed
in either homozygous dominant or heterozygous genotypes
Recessive – trait will ONLY be expressed phenotypically in homozygous recessive individuals
Sex–Linked – alleles are found on the sex chromosomes (both X in females and one X in males – NOT FOUND ON Y CHROMOSOMES!)
Chapter 9: Patterns of Inheritance
A Basic Punnett SquareDimples (d) are a recessive trait. Two heterozygous
individuals want to have children together…
What is the chance their child will have dimples?What is the expected genotypic ratio?What is the chance their child will be without dimples?What is the expected phenotypic ratio?
Chapter 9: Patterns of Inheritance
A Sex-Linked Punnett SquareHemophilia is a sex-linked, recessive trait. A non-carrier
female and a hemophiliac male want to have children…
What is the chance their child will have hemophilia?What is the chance any of their children will be carriers?What are the genotypes of the parents?What are the genotypes for a hemophiliac male? female?
Chapter 9: Patterns of Inheritance
Hardy-Weinberg EquilibriumTo be in equilibrium
NO mutations must ariseNO natural selection can occurNO migration can occurThere must be a HUGE populationCompletely random mating must occur
Chapter 9: Patterns of Inheritance
Hardy-Weinberg Equationp + q = 1
• Where…• p = frequency of the dominant allele• q = frequency of the recessive allele
p2 + 2pq + q2 = 1
• Where…• p2 = frequency of the AA genotype• 2pq = frequency of the Aa genotype• q2 = frequency of the aa genotype
Chapter 9: Patterns of Inheritance
Hardy-Weinberg EquationYou have sampled a population in which
you know that the % of the aa (albino) genotype is 36%.
What is the allele frequency for albinism?What % of the population would be
homozygous for “normal” pigmenting?
Chapter 10: Molecular Biology of the Gene
DNA Structure Hydrogen Bonds connect
nitrogenous bases (A T & G C)
= deoxyribose (sugar)
= phosphate
Chapter 10: Molecular Biology of the Gene
ReplicationWhat? Copying of genetic materialWhen? Prior to cell division (mitosis)Where? inside the nucleusWhy? to ensure all new cells have copies of
genetic informationHow? Base-pairing rule! (A T, G C)
DNA Helicase unzips the double helix.DNA Polymerase adds on new nucleotides
(base pairing) & then “proofreads” the new strands
Chapter 10: Molecular Biology of the Gene
ReplicationWhat? Copying of genetic materialWhen? Prior to cell division (mitosis)Where? inside the nucleusWhy? ensure all new cells have copies of genetic
infoHow? Base-pairing rule! (A T, G C)
DNA Helicase unzips the double helix.DNA Polymerase adds on new nucleotides (base
pairing) & then “proofreads” the new strandsDNA Ligase joins together the completed Okazaki
fragments of the discontinuous (lagging) strand
Chapter 10: Molecular Biology of the Gene
ReplicationSemi-Conservative Process – each
“daughter” strand is made up of one new strand and one original strand
Original Strand: CTAATGTComplimentary Strand: GATTACA
Chapter 10: Molecular Biology of the Gene
TranscriptionWhat? Creation of an mRNA “copy” of a geneWhen? Prior to gene expressionWhere? inside the nucleusWhy? the express genes without endangering
actual DNAHow? Base-pairing rule! (A U, G C)
RNA Polymerase creates a strand of mRNA complimentary to the segment of DNA being expressed
Chapter 10: Molecular Biology of the Gene
TranslationWhat? “Reading” of the mRNA to create a
polypeptideWhen? Following transcriptionWhere? On/In the ribosomeWhy? To create proteins that express genesHow?
mRNA attached to ribosome ribosome “reads” codons (3-nucleotide segments) tRNA transfers individual amino acids to ribosome ribosome joins amino acids until a STOP codon is
reached and the chain is released
Chapter 10: Molecular Biology of the Gene
Biotechnology & Genetic Engineering:have improved crop yieldshave led to pest resistant cropshave led to new varieties of fruits and veggieshave aided in crime investigationshave led to the development of more effective
medical treatments
Chapter 10: Molecular Biology of the Gene
DNA FingerprintingRestriction enzymes are used to break DNA
into specific segmentsTreated DNA is placed in a chamber with a
positive & negative endElectrophoresis is used to separate the DNA
fragmentsThe banding patterns created are compared to
determine DNA matches & paternity
Ecology & the Environment
Goals of Conservation Biology:enforce environmental lawsprotect habitats
protects not only habitats, but also interactions between many different species
the rainforest has been particularly valuable in discovering new species that provide ingredients for new medications, food, and other goods
manage natural resourcesusing alternative energy, decreasing reliance on
coal, and driving more efficient autos are sustainable practices that reduce acid precipitation
Ecology & the Environment
Integrated Pest Managementusing a variety of approaches including biological
control, pesticides when necessary and monitoring of pest populations
Problems Related to Pesticidesbiological magnificationpesticide resistancegood bugs can be killed along with pests
Introduced Speciesoften become pests because they have no natural
predators to keep their population in check
Questions???
