Biology Exam

8/2/2019 Biology Exam

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Exams BiologyDarren Miler

Genetics

Section 4.1 The Nature of Heredity:Asexual and sexual reproduction onlyDefine the following terms:heredity: the process of traits being passed from parents to offspringgenetics: study of hereditygene: segment of DNA that provides the instructions for the building and regulation of afunctional molecule in the cellcell cycle: pattern of cell growth and division; interphase, mitosis, cytokinesis

interphase: growth, performance of function, duplication of DNAg1 phase: preparation for duplication of DNAs phase: duplication of DNA

m phase:division of cell

g2 phase: preparation for division of cellmitosis / meiosis: division of DNAcytokinesis: division of cytoplasm, organelles, cell membrane

DNA: deoxyribonucleic acidfunction: contains genetic information of celllocation: nucleuscomposition:AKA base sub-units (A, T, G, C)structure: molecule with two strands and a double helix shapeconnection:A -> T, G -> C

chromatin: DNA in uncondensed form during interphasechromosome: DNA in condensed form during prophase, metaphase of mitosischromatid: DNA in condensed form in half during anaphase of mitosiscentromere: midpoint of chromatids forming chromosomelocus: the location within a chromosome where a gene is foundspindle apparatus: move and arrange DNA during mitosis; centrosome + spindle fibre

centrosome: structure helping to form spindle fibrespindle fibre: structure facilitating movement of DNA

tetrad: aligned homologous chromosomessynapse: alignment of homologous chromosomes

somatic cell: non-reproductive cell; contain 46 chromosomes

diploid: containing all the chromosomesgamete cell: reproductive cell; contain 23 chromosomes

haploid: containing half the chromosomeszygote: result of a gamete fertilizing an ovumautosomes: the 22 non sexual human chromosomessex chromosome: the 23rd sexual human chromosome


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asexual reproduction: the production of offspring from a single parent, resulting in offspringwith identical genetic makeup as the parent; advantages include the fact that the parent celldoes not have to seek a mate, does not have to form specialized mating techniques, and doesnot have to possess reproductive organssexual reproduction: the production of offspring from the fusion of two sex cells, resulting inoffspring with a different genetic makeup then the parent; advantages include the insurance of

diversity, and disadvantages include mating techniques which attract predators

Section 4.2 Asexual Reproduction: Copies and Clones: Mitosis cloningmitosis: division of DNA in asexual cell

prophase:i. chromatin -> chromosomesii. nuclear membrane, nucleus break downiii. spindle fibres form from centrosomes at poles

iv. chromosomes attach to the spindle fibres by the centromeresmetaphase:i. chromosomes align along equatoranaphase:i. centromeres divideii. spindle fibres separate chromatids towards opposite polestelophase:i. chromatid -> chromatinii. nuclear membrane, nucleus reformiii. cell membrane begins to divideiv. spindle fibres break down

Section 4.3 Sexual Reproduction: Adding Variety: Meiosis gametogenesis

meiosis: division of DNA in sexual cellprophase1:i. chromatin -> chromosomesii. homologous chromosomes synapse, exchange DNAiii. nuclear membrane, nucleus break downiv. spindle fibres form from centrosomes at polesv. chromosomes attach to the spindle fibres by the centromeresmetaphase1:i. homologous chromosomes align beside each other along equatoranaphase1:i. spindle fibres separate homologous chromosomes towardsopposite poles

telophase1:i. cell membrane begins to divideii. spindle fibres break down[cytokinesis1]:i. cytoplasm, organelles divideii. cell membrane dividesprophase2:i. spindle fibres reformii. chromosomes reattach to spindle fibres via centromeres


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metaphase2:i. chromosomes align beneath each other along equatoranaphase2:i. spindle fibres separate chromatids towards opposite polestelophase2:i. cell membrane begins to divide

ii. spindle fibres break downiii. chromatid -> chromatiniv. nuclear membrane reforms

Section 4.4 Abnormal Meiosis and/or Fertilization: Know what non-disjunction is andhow/when it occurs remainder of the sectionDefine the following terms:monosomy: the presence of one chromosomedisomy: the presence of two chromosomestrisomy: is the presence of three chromosomestetrasomy: the presence of four chromosomesWhat is non-disjunction?Non-disjunction describes a mistake during meiosis wherein homologous pairs or sister

chromatids fail to separate during anaphase, causing the gametes to possess either too few ortoo many chromosomes.Section 5.1 Mendelian Inheritance: Know the entire section to the extent covered in classTest crosses Bloodline theory?Define the following terms:allele: one of two or more alternative forms of a gene that arise by mutation and are found atthe same place on a chromosome.dominant allele:the allele for which the phenotype is observed in heterozygous individuals;indicated by a big letter placed first in the genotyperecessive allele: the allele for which the phenotype is not observed in heterozygous individuals;indicated by a small letter placed second in the genotypegenotype: the genetic makeup of an individual

phenotype: the part of an individuals genetic makeup which is expressed in his or her traitshomozygous: an individual that carries two of the same alleles for a given characteristicheterozygous: an individual that carries two different alleles for a given characteristic

Describe the method of Gregor Mendel that led him to develop Mendelian Inheritance,and explain any specifics.Gregor Mendel crossed organisms to analyze patterns of gene transmittance. He used peaplants because these possess many traits with two specific forms, i.e. tall or short, smooth orrough seeds, purple or white leaves, etc, which allowed Mendel to see clearly how traits appearand disappear in progeny; in other words, by using definite characteristics, he could clearly trackinherited traits.What control did Mendel introduce into his experiments?

Mendel used purebred pea plants. A purebred plant is produced by crossing progeny over andover until the results consistently demonstrate the same characteristic, firmly establishing thefact that the recessive alleles have been eliminated.Describe Mendels crosses.In Mendels first cross, a tall pea plant (TT) was crossed with a short (tt) to produce four talloffspring (Tt.) In Mendels second cross, the tall plants (Tt) produced three tall plants and oneshort plant (TT, Tt, Tt and tt.)Describe the relevant terminology to Mendelian crosses.


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P, F1, F2 The generations of crosses, starting from the original and descending into thecrosses of the subsequent offspring.What laws did Mendel propose based on his crosses?

1. Mendels Law of Segregation: (a) Organisms inherit two copies of genes, one from eachparent and (b) Organisms donate only one copy of each gene to their gametes becausethe genes separate during gene formation

2. Mendels Law of Independent Assortment: When considering multiple traits, every traitsegregates completely independent of every other trait, i.e. the segregation of alleles fora specific gene have no impact on the segregation of alleles for a different gene.

Section 5.2 Variations in Heredity Entire sectionWhat is incomplete dominance?Incomplete dominance is a situation where the dominant allele is only partially dominant overthe recessive allele. If a trait has a dominant and a recessive allele assigned to it, the dominantallele might influence seventy five percent of the phenotype while the recessive allele mightinfluence twenty five percent of the phenotype.What is co-dominance?Co-domionance is a situation where the dominant allele is not at all dominant over the recessiveallele. If a trait has a dominant and a recessive allele assigned to it, the dominant will influence

fifty percent of the phenotype while the recessive allele will also influence fifty percent of thephenotype.Section 5.3 Pedigrees Tracking Inheritance: Sex-linkage onlyPedigreesWhat is sex linkage?Linkage is the presence of two or more genes at the same chromosome. This influences thelikelihood of a particular trait being present given the presence of a given particular trait.What is recombination?Recombination is the change in the arrangement of linked genes due to crossing over inProphase 1, whereby genes that were formerly linked are now found on separatechromosomes.How is the distance between one gene and the next measured?The distance between one allele and the next is measured in units known as centimorgans.

How do rates of recombination differ based on how closely linked genes are to oneanother?Genes closer together on the chromosome are less likely to undergo recombination becausethe area at which the gene could crossover to result in recombination is much smaller, andtherefore much less mathematically probable.Section 5.5 Genetic DisordersSection 5.7 Multi-trait Inheritance Entire SectionWhat is the difference between a monohybrid and a dihybrid cross?

A monohybrid cross is a cross that involves one gene while a dihybrid cross is a cross thatinvolves two genes.EvolutionSection 7.1 Biological Change Over Time: Mutations only

What is a mutation?A mutation is a change in the genomic sequence of the DNA or of the RNA; occurs 1/10 000 celldivisions.What causes a mutation?1) Exposure to external stimuli, e.g. radiation or carcinogen 2) Error during copying of DNAWhat is fitness?Fitness is the likelihood of an organism to reproduce.How are mutations and fitness connected?


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A beneficial mutation increases an organisms fitness, a harmful mutation decreases anorganisms fitness, and a neutral mutation has no effect on an organisms fitness.Section 7.2 The Evolution of an IdeaSection 7.4 The Evidence for Evolution Know this section to the extent covered in classWhat is evolution?Evolution is the process in which significant changes in the inheritable characteristics of a

species occur over time.How is evolution observed?Evolution is observed through fossils. Transitional fossils are fossils of organisms that showlinks between groups.What is a fossil?

A fossil is a preserved remain or trace of on organism or its activity, including fossilized bones,footprints, dung or plants.What is a permineralized fossil?

A permineralized fossil is a fossil upon which crystals are found. These fossils form in aqueousenvironments, and as the fossils form, salts crystallize out on the fossil.How do fossils form?

1) The organism dies 2) The organism is covered by sand and sediment 3) Heat and

pressure on the specimen convert the bone into stone 4) Wind and precipitation revealthe fossils at the surface 5) Paleontologists find the fossilsWhat are two methods of fossil dating?1) Stratigraphic dating 2) Radiometric datingWhat is Stratigraphic dating?Stratigraphic dating is a method of providing the relative age of a specimen based onthe layer of ground in which it is found. It works on the premise that fossils in deeperlayers of rock are older than fossils in more shallow layers.What is Radiometric dating?Radiometric dating is a method of providing the absolute age (in years) of a specimen. Itworks on a number of premises. Firstly, it is understood radioisotopes (unstable forms

of an element which give off neutrons to become more stable) decay at a constant rate.Secondly, it is understood it the half-life (time it takes for half of the sample to decay)takes 5730 years.Describe an example of Radiometric dating.Since the ratio between C-14, the parent isotope, and N-14, and daughter isotope, isknown, it is possible to look at an organism and find the ratio of C-14, extrapolate whatthe ratio of N-14 should be, compare this to the actual presence of C-14, and therebycalculate the age of the specimen.When a specimen is 100% 14C, it is entirely UNSTABLE.When a specimen is 50% 14C, and 50% 14N, it is on its way to becoming STABLE.

# of Half Lives Proportion C14/N14 Time Passed

0 100% C14/0%N14 01 50% C14/ 50% N14 5730

2 25% C14/ 75% N14 11460

3 12.5% C14/87.5% N14 17190

Section 7.5 On the Origin of Species Know this section to the extent covered in classWhat were the trends that led to Charles Darwins Theory of Evolution by NaturalSelection?


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1) Individuals within a species vary in many ways.2) Some of this variability can be inherited.3) Every generation produces far more offspring that can survive and pass on their variations.4) Populations of species tend to remain stable in size.Describe the observations and corresponding hypotheses that Darwin made.1) Biogeography

Observation: Darwin observed the impacts of biogeography, which is the analysis of thegeographic distribution of organisms. He noticed that the geographic proximity of a species hada larger impact on to another had a larger impact on its similarity than a common environment.Hypothesis: Similarity between species is due to the fact that all of these species are derivedfrom a small number of ancestral species.2) Homologous and Analogous FeaturesObservation: Darwin observed that some organisms possessed homologous features, which arefeatures that have a similar structure to those of other organisms. An example of this type oftrait is the vertebrate forelimb shared by whales, cats, horses, birds and humans. Meanwhile,other organisms possessed analogous features, which are features that have a similar functionto those of other organisms. An example of this type of feature is the wings of doves andbutterflies.

Hypothesis: Organisms with homologous features likely share a more recent common ancestorthan organisms with analogous features.3) Vestigial FeaturesObservation: Darwin observed that certain organisms had features that had no useful purposebut were homologous to fully functioning structures in related species. An example is thehipbone in the whale.Hypothesis: Vestigial features are the remnants of an ancestor species for whom the featurewas useful but which is no longer useful and which evolution has yet to remove.4) Artificial Selection and EvolutionObservation: Darwin observed that all species possess inherited variations that can be selectedto change the species in desirable ways. Examples include pigeons and dogs.Hypothesis: Certain circumstances can bring about the selection of one potential trait over

another potential trait through natural mechanisms.Section 7.6 The Modern Theory of EvolutionSection 8.1 Natural Selection Know this section to the extent covered in classWhat is microevolution?Microevolution is a small scale evolutionary process that causes changes in the genotypes andcorresponding phenotypes within a species.On what level does selection act?Selection acts on the level of the phenotype, because only the alleles that produce beneficialphenotypes and therefore enhance the fitness of an individual will be selected for.What are the four patterns of selection?1. StabilizingSelection for the most common variations of a trait. This is caused when the species is well

adapted to its environment, and the selection pressure maintains the more common phenotypesbecause it is advantageous for survival.2. DirectionalSelection for the less common variations of a trait. This is caused when the species moves to anew environment, and the selection pressure causes an adaptation towards the less commonphenotype because it is advantageous for survival.3. Disruptive


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Selection for the variations at either extreme of a trait. This is caused when species move to anew environment, and the selection pressure causes adaptation towards variants at bothextremes because it is advantageous for survival.4. SexualSelection for the variations of a trait that influence the mating success of the species.What does sexual selection lead to?

Sexual selection leads to sexual dimorphism, or differences in physical appearance betweenmales and females.Explain how evolution can be considered a compromise among selective pressures.

A certain trait can be beneficial in one regard, and therefore it will be selected four under onepattern of selection, even though it is harmful according to the standards of another pattern.One example is the feathers of peacocks, which attract mates but also attract predators.Which pattern of selection is responsible for evolution?The pattern of directional selection is chiefly responsible for evolution since it is the one thatdirects species towards adaptations which they did not previously possess. Incidentally,disruptive selection could also lead to evolution, but this would only be true where the variantsat either extreme being selected for also represent directional selection in that they are lesscommon than the traits not being selected for.

What is the mechanism that underlies evolution?Cumulative selection is the mechanism that underlies evolution, and it is defined as theaccumulation of many small evolutionary changes over time which results in significant newadaptations relative to the ancestral species. For example, this is the mechanism that explainsthe evolution of the eye, which likely evolved from a light sensitive cell, to a light sensitive pit, toa pin hole eye, and finally, to a lens based eye.Describe how evolution can have an affect not only within a species but also betweenspecies.Evolution can promote evolutionary relationships between species. For example, plants likelyevolved sticky pollen in order to attract insects which could then disperse it with a greaterdegree of accuracy than the wind can. Meanwhile, the insects benefit from this arrangementsince there now exist a greater number of food sources for them. Thus, evolution has benefited

both species simultaneously.What is altruism?

Altruism is a relationship between organisms in which one directly benefits much more than theother. An example are bee colonies in which the females help the queen bee reproduce ratherthan reproducing themselves so that the alleles within the hive are more consistent whichpromotes cooperation of the colony. This arrangement is better for the bees in general, but notfor many of the individual bees that are involved.What is kin selection?Kin selection is the natural selection of a trait of one individual which enhances the success ofclosely related individuals. For example, an animal that sacrifices itself for its offspring makes itsability to reproduce impossible, however, the chances of its alleles being passed on through thechild are now greater.

Section 8.2 Speciation Know this section to the extent covered in classWhat is macroevolution?Macroevolution is a large scale evolutionary process that causes changes in the genotypes andcorresponding phenotypes between species, i.e. that leads to the production of new genera oreven taxa.What is a species?

A species is any group of organisms able to interbreed under normal conditions.What is speciation?


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Speciation is the formation of completely new species through progressive microevolution. Asenough change happens, organisms are separated through reproductive isolation and becomenew species.What is one method of differentiating species?Species can often be differentiated based on physical characteristics as well. For example, fourfinches with four different beaks are four different species.

What is another method of differentiating species?Species can be differentiated by their reproductive isolating mechanisms, which are thebehavioral, structural or biochemical traits that prevent members of different species fromreproducing.What are the types of reproductive isolation mechanisms?1) Prezygotic, i.e. preventing mating or fertilization

1. Behavioural isolation difference in mating rituals2. Ecological isolation geographical or habitat isolation3. Temporal isolation breeding seasons do not match4. Gametic isolation chemical markers on sex cells are unrecognizable5. Mechanical isolation sexual organs are incompatible

2) Postzygotic, i.e. preventing development of a zygote into a healthy adult

1. Zygotic mortality fertilized zygotes from separate species do not reach maturity2. Hybrid inviability hybrid offspring are born but die early3. Hybrid Infertility hybrid offspring are born and reach adulthood but are infertile

What are the two forms of speciation?1. Allopatric Speciation: Populations are genetically the same but become geographicallyseparated from one another leading to speciation2. Sympatric Speciation: Populations remain in the same location but become geneticallyisolated through mutation leading to speciationWhat is genetic drift? How does it differ from normal selection?Genetic drift is changes in allele frequency due to chance as opposed to selection. It differs fromnormal selection in that the changes are not due to advantages provided by a particularphenotype either for survival or for fitness, but is related to external factors instead.

What are three types of genetic drift?1. The Bottleneck Effect: Events (e.g. a catastrophe, hunting) result in a random, drasticreduction in population size, leading to significant changes in relative allele frequencyExample: The elephant seal. Excessive hunting caused complete homozygosity i.e. all have thesame genotype.2. The Founder Effect: A few individuals from a larger population leave to establish a newpopulation, leading to significant changes in relative allele frequency.Example: The Amish community. 30 people from Switzerland generated the entire Amishcommunity.3. Gene Flow: Migration of organisms between populations, leading to significant changes inrelative allele frequency in both populations.Example: Prairie dogs. Prairie dogs move between populations every summer. This reduces the

difference between the populations, but increases the difference within the populations.Section 8.3 Patterns of EvolutionSection 8.5 Macroevolution: Know gradualism and punctuated equilibrium onlyWhat problems are there with the Theory of Evolution?One of the main problems with the Theory of Evolution is the gaps in the fossil record.What explanations exist for this gap?1) Darwin suggested that the fossils existed but had not yet been found. 2) Gould and Eldredgesuggested that the fossils never existed due to the fact that the species were created duringperiod of rapid change and didnt have time to fossilize.


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What is the official name of Darwins theory?His theory is known as the Theory of Gradualism, the idea being that changes accumulate overlong period of time that result in the formation of new species.What is the official name of Gould and Eldredges theory?Their theory is known as the Theory of Punctuated Equilibrium, the idea being that evolutiongenerally takes place at a constant rate but is occasionally interrupted by rapid change.

Diversity of Living ThingsSection 1.1 Biodiversity An IntroductionSection 1.2: The Nature of Classification: Taxonomy, Carl Linnaeus and binomialnomenclature, Classification and the kingdoms of life, Dichotomous keysWhat is the biosphere?The biosphere is a 16 kilometer thick layer of soil, water and air surrounding the earth in whichall of life an estimated 30-100 million species live. To date, only 1.75 million have beendiscovered.What is taxonomy, and why do we use it?Taxonomy is the organization of the diversity of life. We use it to make sense of the diversity ofspecies present on earth.What types of classification have been used historically? What were the problems?

1. Classification by Habitat, i.e. land / water / air (Aristotle)2. Classification by Potential for Harm, i.e. harm / superfluous (St. Augustine)3. Classification by Material Produced, i.e. fruit / vegetables / wood (Herbalists)The fundamental flaw to all of these approaches was that they were either too broad oralternatively did not cover the entire range of possibilities, and so there were a ton ofexceptions!What system of taxonomy do we use today?Today we use the Linnaean system produced by Carl Linnaeus. It is organized into seventaxons, or types of groups. It is advantageous because it is much more dynamic, in that itstarts with broad categories and gradually moves towards the specifics so as to reflect the richdiversity of life. In other words, it incorporates an expedient system of groups within groups.What is the system of naming in taxonomy?

Taxonomy is based on binomial nomenclature, i.e. the organism is identified by its genus andspecies. For example, Homo sapiens refers to the genus Homo and the species sapiens.(Note: Only the genus is capitalized, and the entire term must either be italicized or underlined).How are organisms classified?Organisms are classified using dichotomous keys. This is a binary selection scheme forgrouping organisms. It places organism into groups by including two choices for eachcharacteristic; often they take the form of a question with either a yes or no answer.Go through the Linnaean system.

mnemonic: King Philip Cleans Oranges Fast, Gene Spoke!1. Kingdom

mnemonic: Aunt Platyss Fun Principal Elates Archie1. Animalia

2. Plantae3. Fungi4. Protista5. Eubacteria6. Archaebacteria

2. Phylum3. Class4. Order5. Family


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6. Genus7. Species

Section 1.3: Phylogeny and Modern Taxonomy, Phylogeny, Phylogenetic trees and cladesWhat is phylogeny?Phylogeny is the science that deals with the evolutionary relationships between and amongspecies.

What is evidence of common ancestry?1. Similar Stages of Development, for example pigs, fish and humans2. Similar Anatomical Structure (Homology), for example whale, cat, horse and human forearms3. Similar DNA Sequence, for example human, mouse and rat RB1 genesWhat is a phylogenetic tree?

A phylogenetic tree is a visual depiction, or summary, of the evolutionary relationships betweenspecies.How does the tree work?The close to the trunk a species is, the older it is. Branch points within a tree represent pointswhere ancestors led to the development of new species. A clade is a grouping of species withina phylogenetic tree which includes the ancestor and all of its descendants.Section 1.4 Kingdoms and Domains: Overview of kingdoms only

Provide an overview of the kingdoms:Kingdom Size Euk /

ProMulti /Singlecell

Hetero /Autotrophic

Sexual /asexual

Examples Environments(for most)

Animalia 1200000

Eukaryotic

Multi Hetero Both humans Terrestrial /Aquatic

Plantae 250000

Eukaryotic

Multi Auto Both mosses Terrestrial

Fungi 100000

Eukaryotic

Both Hetero Both mushrooms,moulds, yeasts

Terrestrial

Protista 100000

Eukaryotic

Both Both Both amoeba, algae Aquatic

Eubacteria 10

000

Prokary

otic

Single Both Asexual E coli, salmonella

Archaebacteria 400 Prokaryotic

Single Both Asexual thermophiles,methanogens

Aquaticdigestive tracts

Section 2.1 The Prokaryotes: Eubacteria and Archaea: Know everything regarding eubacteriaand archaeWhat is the difference between archaebacteria and eubacteria?

Archaebacteria 1) are the oldest form of life on earth and 2) live in the most extremeenvironments, for example extreme heat, extreme cold, high salt and 3) these bacteria are theones least commonly associated with disease.Eubacteria 1) are more recent forms of life on earth and 2) live in less extreme environmentsand 3) these bacteria are the ones most commonly associated with disease.

How are bacteria classified?In two ways, 1) by cell shape and 2) through gram staining1) Cell shape:

a) Cocci spheresi) Monococci ii) Diplococci iii) Streptococci iv) Staphylococci

b) Bacilli rods


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i) Diplobacilli ii) Streptobacilli

c) Spirillum spirals note: close up, these spirals are made of rectangular cells

2) Gram staining: a solution made up of crystal violet and iodine which stains the cell walls ofthe bacteria

a) Gram Positive Bacteria: the bacteria absorbs the stain and becomes purpleb) Gram Negative Bacteria: the bacteriadoes not absorb as much of the stain andremains pink note: these tend to be more infectious types of bacteria, e.g. bacteriumcausing meningitis

Describe the functions of the parts of a bacterium.Pili: latch on to other organismsFlagella: facilitate movementCapsule: prevent other organisms from latching oPlasmid: contains genetic information

How do bacteria receive nutrition?Archaebacteria can eat almost anything and do not require classification. Eubacteria cannot eatanything and do require classification.

Eubacteria are separated into 1) autotrophs and 2) heterotrophs.1) Autotrophs: organisms capable of producing their own food

a) Photoautorophs: uses light energy to make its own food (example: photosyntheticbacteria: photosynthesis takes place on membranes in the cytoplasm)b) Chemoautotrophs: uses chemical energy to produce food (example: bacteria thatconsumes oil)

2) Heterotrophs: organisms that obtain food from external sourcesa) Chemoheterotrophs: break down organic matter in their environment to obtain food

and produce energyWhat are the requirements for oxygen for different bacteria?1) Obligate aerobes: require oxygen to convert food to energy2) Obligate anaerobes: must be in an environment without oxygen to convert food to energy3) Facultative Anaerobes: can produce energy from food with or without oxygenDescribe the process of bacterial reproduction.Binary fission (asexual): division of parent cell into two genetically identical daughter cells

Conjugation (sexual): bacterial cell passes a copy of a plasmid to a nearby cell through a pilus

Transformation: bacterial cell takes in an uses pieces of DNA from its environment that havebeen released by dying DNAHow do bacteria protect themselves when the cell is under stress?The bacteria will produce an endospore, a highly resistant and dormant structure that formsaround the chromosome and protects it from damage


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Describe the carbon cycle and the role bacteria play in it.1) Organic molecules (ex. glucose) are produced by plants and some bacteria2) Larger organisms consume organic molecules3) Larger organisms die4) Bacteria convert the carbon in the organism back into carbon dioxide5) Plants use carbon dioxide to perform photosynthesis and produce organic molecules

What is the importance of bacteria?1) Bacteria decompose dead organisms and recycle energy back into the environment2) Bacteria contain enzymes which breaks food into molecules3) Bacteria that are beneficial to ones health can fight those which are harmfulClassify archae by their environments.Thermophiles live in heat, Halophiles live in salt, Methanophiles live in gas, Psychrophiles live inextreme cold.Section 2.2 Viruses Viroids and PrionsWhat is a virus?

A virus is a non-cell particle made up of genetic material surrounded by a capsid i.e. a proteincourt.Are viruses alive?

To live, an organism must: 1) reproduce independently of all others cells 2) respire i.e. breakdown glucose into energy) 3) metabolize energy. Since viruses do not engage in any of theseactivities they are not considered alive.Classify viruses.1) DNA viruses: DNA is their genetic material2) RNA viruses: RNA is their genetic material3) Retroviruses: RNA is their genetic materialHow do viruses reproduce?Viruses reproduce by inserting their genetic material into a host cell and hijacking the biologicalmachinery in order to make more viruses.Describe the method of reproduction for DNA viruses.1) Lytic phase: leads to the death of the host cell

a) virus attaches to host cell using the tail fibres and injects its DNA through the tailb) host DNA is destroyed and viral DNA uses cell machinery to make more viral DNA,protein coats, tails and fibresc) viral components are assembled into new virusesd) cell wall + membrane of bacterium break down and new viruses are released

2) Lysogenic phase: does not lead to the death of the host cell [harsher conditions]a) virus attaches to host cell using the tail fibres and injects its DNA through the tailb) viral DNA is inserted into host cells DNA

Describe the method of reproduction for RNA viruses.a) virus attaches to host cell using the tail fibres and injects its RNA through the tail

b) viral RNA uses cell machinery to make more RNA, protein coats, tails and fibresc) viral components are assembled into new virusesd) cell wall + membrane of bacterium break down and new viruses are released

Describe the method of reproduction for retroviruses.a) virus attaches to host cell using the tail fibres and injects its RNA through the tailb) viral RNA converts into DNAc) viral DNA is inserted into host cells DNAd) viral components are assembled into new viruses


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e) cell wall + membrane of bacterium break down and new viruses are released

Section 3.1 The Fungi: Know all of fungi to the extent covered in class Do I have enough?Classify the fungi kingdom:1) Zygomycota: use sporangium to make spores2) Ascomycota: use ascus to make spores, e.g. moulds and mildew

3) Basidiomycota: use basidium (fruiting bodies) to make spores, e.g. mushrooms and puffballsDefine the terms hyphae, chitin, stolon, rhizoid, sporangium, condiaChitin: complex chemical found in cell walls of fungi that make it rigid

Hypha: thin filaments that grow off the fungus; stolons and rhizoidsStolons: grow on the surface of foodRhizoids: grow inside food absorbing sugar and waterSporangium: structure of a zygomycota within which diploid spores are produced; these are carried awayby the wind to develop into new fungi; Condia: Chains of diploid spores which are formed at the end of thehyphae in the ascomycotaHow do fungi receive nutrition?

Fungi eat via endocytosis, the taking in of matter by a living cell through invagination of itsmembrane to form a vacuole. Mycelium increase the surface area for digestion.

Describe the general process for fungi reproduction.1) Bacteria is dikaryotic (two separate nuclei)2) Nuclei fuse to form diploid zygote3) Zygote undergoes meioses to produce four haploid spores4) Spores nucleus replicates to form hyphae5) Hyphae from different cells fuse to produce dikaryotic mycelium6) Mycellium grows into mature adultDescribe the importance of fungi.1) Yeast ferments beer and wine2) Penicillin3) Decomposeres4) Mychorrizia protect plants from diseases

5) Lichens protect green algae and nourishes water

Describe the growth and reproduction (ideal and harsh conditions) of the differentclasses of fungi.

Growth Reproduction

Ideal (asexual) Harsh (sexual)

Zyg.

Produce stolons andrhyzoids

Produce sporangiumProduce hyphae ofdifferent mating types toproduce dormant

zygosporeHyphae of differentmating types form. Thesefuse, either from the samefungus or from differentfungi, to produce a diploidzygospore, which remainsdormant until betterconditions arise.


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Asc.

Produce stolons

Produce condia.Produce ascus.

Ascus: haploid spores

which are carried by thewind and fuse with sporesof opposite mating types

Bas.

Produce fruitingbodiesHyphae growunderground in wet ordamp conditions andpush up through thesoil to form the fruiting

body, a sporeproducing structure

The cap of the mushroom is the site of sporereproduction. Inside each basidium (sheets oftissue) are 1000s of haploid spores which areblown away by the wind to form a haploidmycelia (network). Mycelia of oppositemating types meet to form a diploid mycelia.

All cells have two nuclei, which fuse to form anew fruiting body.

Section 3.2 The Plants: Know general characteristics, Alternation of generations, Non-vascular vs. Vascular categories of plantsWhat is alternation of generations?

Alternation of generations is the lifecycle of plants. A sporophyte (diploid stage) undergoesmeiosis to produce asexual spores (haploid stage.) The spores grow into gametophytes whichmature and produce gametes. Gametes undergo fertilization to form diploid zygotes. Thesegrow into sporophytes.

Distinguish between vascular and non vascular plants.Vascular plants have conducting tissue for transport of nutrients and non vascular plants do not.

Distinguish between the different types of vascular plants.Gymnopserms are vascular plants that produce seeds in cones and are fertilized by the wind.

Angiosperms are plants that produce flowers and are fertilized by plants.Identify the reproductive structures in plantsPollen contains the male gametes, ovules contain the female gametes, and seeds are thefinished zygote.What is a type of vascular plant?Trachophytes are vascular plants. They have oxylem and phloem.What is a type of non vascular plant?


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Bryophytes (mosses) are non-vascular plants. They lack roots, stems and leaves.

Section 3.3 The Animals: Know all of animals to the extent covered in classHow can animals be classified?

Animals can be classified into vertebrates and invertebrates, or those having or not having a

backbone, respectively.What two phylums have we studied in this kingdom?1) Poriphera (sponges) and 2) Cnidaria (jellyfish)Describe characteristics of the sponge.water current

1) Mostly marine2) Sessile (does not move)What role does the water current play in the sponge?1) The water carries food into the sponge.2) The water carries oxygen into, and carbon dioxide out of, the sponge.How does the sponge reproduce?

ReproductionIdeal(asexual)

Harsh (sexual)

Budding Sponges are hermaphrodites (produce egg and sperm.) Water currents carrythe egg and sperm to other egg and sperm to be fertilized.

Describe characteristics of the jellyfish1) Radially symmetrical

Describe the reproduction of the jellyfish.

Reproduction

Ideal (asexual) Harsh (sexual)Polyp stage Meduca stage

Animals: Structure and FunctionDescribe the constitution of organisms.Organisms are made of organ systems which are made of organs which are made of tissueswhich are made of cells.Describe the chemical process of cellular respiration.C6H12O6 + O2 CO2 + H20Section 9.3 Introducing Digestion: Know this section to the extent covered in class; Section9.4 Digestion in the Mouth and Stomach: Know this section to the extent covered in class;


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Section 9.5 Digestion in the Small and Large Intestines: Know this section to the extentcovered in class, Accessory organsWhat is the function of the digestive system?The function of the digestive system is to extract nutrients from food. This takes place through:1) mechanical digestion, the shredding, grinding and tearing of food; 2) chemical digestion, thebreaking down of food by enzymes and other chemical compounds; and 3) absorption, the

transfer of nutrients from the digestive tract into the bloodstream.What four processes are involved in the digestive system?Ingestion: taking in the food.Digestion: breaking down the food

Absorption: transferring nutrients to cellsEgestion: excreting wasteWhat is the central component of the digestive system?The central component of the digestive system is the digestive tract, a long tube from mouth toanus which is present in most forms of life.What structures does food pass through in the digestive tract?1) Oral cavity 2) Pharynx 3) Esophagus 4) Stomach 5) Small intestine 6) Large intestine 7) Anus

Describe the structure and function of the parts in thedigestive tract.1) Oral cavity: Mouth and all its componentsi) teeth: tear up food into small pieces; (incisors and canines cut,premolars and molars grind)ii) tongue: manipulates and directs food towards the teeth;iii) lips: aid in the dismantling of food;iv) saliva: contains an enzyme to breakdown starch known asamylase.

2) Pharynx: Tube connecting the mouth to the esophagus which receives bolus that has passedover the epiglottis, a flap of skin which covers the trachea as food is passing by

3) Esophagus: Muscular tube connecting the pharynx to the stomach which transports foodthrough peristalsis, a process of coordinated contraction of muscles in a part of the esophagusthrough which the bolus has already passed, and the relaxation of muscles in a part of theesophagus where the bolus has not yet reached

4) Stomach: J-shaped reservoir of food featuring two rings of muscle on either end, comprisedof:i) Cardiac sphincter (Lower esophageal sphincter): Regulates flow of food from the esophagusinto the stomach, and prevents backflow of food into the esophagus

internalcomponents

ii) Pyloric sphincter: Regulates flow of food from stomach to small intestineiii) Ruguae: Folds of tissue which allow for expansion of stomach as needediv) Digestive acids and enzymes: Break down foodv) Hydrochloric acid: Sterilizes upper digestive tract, and kills invading microbes, andactivates pepsinvi) Pepsin: Enzyme which breaks down protein

5) Small intestine: The site of absorption of nutrients, comprised of:


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i) Duodenum: Fingers of tissue coated with villi and microvilli that provide a surface area for theabsorption of nutrientsii) Jejunum: Major site of digestion and chemical absorption which is covered with villiiii) Ileum: Tubular structure with villi that continue absorption of nutrients from food

6) Large intestine: The secondary site for absorption of nutrients, comprised of:

i) Caecum: Receives chyme from small intestine and continues absorbing nutrientsii) Colon: Reabsorbs water and vitamins.

7) Rectum and Anus: End of digestive tract and opening where wastes are removed from thebodyWhat component of the mouth officially initiates digestion?The saliva initiates digestion.What is food called after it has been processed in the mouth?

At this point food is called bolus, which denotes food in its broken down state. The mouthbreaks food down into bolus because it is much easier to swallow.What is food called after it has been processed in the stomach?

At this point food is called chime, which denotes a liquefied paste of nutrients.

Why are the small intestine and the large intestine so called?It is called the small intestine because its diameteris small, not its length. By contrast, the largeintestine is large in diameterbut is not as large in length.Section 9.6 Nausea, Vomiting and DiarrheaSection 10.1 The Need for a Respiratory System: Know this section to the extent coveredin classSection 10.2 Respiratory Structures and Processes: Know this section to the extentcovered in classGet diagramsDescribe the parts of the respiratory system.1) Mouth: Brings air into the body2) Nose: Brings air into the body after moistening and warming it

3) Pharynx: Tube connecting mouth and nose to larynx4) Larynx (voice box): Tube structure between the pharynx and the trachea responsible forvocalizations5) Trachea: Tube connecting larynx to the lungs, supported by thick rings or cartilage to supportand prevent collapse6) Bronchi: Tubes that subdivide off the trachea7) Bronchioles: Tubes that subdivide off the bronchi8) Alveoli: Small sacs at the end of the bronchioles that are the site of gas exchange, as O2diffuses from the air inside the alveoli into the bloodstream and CO2 diffuses from thebloodstream into the air inside the alveoli, in order to balance the concentration of gasesSection 10.3 Transport and Diffusion of GasesSection 10.4 Interference with Gas Exchange: Know this section to the extent covered in

classSection 10.5 Lung Transplants and Other TechnologiesSection 11.1 The Need for a Circulatory System: Types of circulatory systems Know theremainder of the section to the extent covered in classSection 11.2 Blood: A Fluid Tissue Know this section to the extent covered in class Section11.3 Blood Vessels Know this section to the extent covered in class Section 11.4 TheCardiac Cycle and Circulation Know this section to the extent covered in classDescribe the components of the circulatory system:1) Heart


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i) Right and left atriums: Receive bloodii) Right and left ventricles: Deliver bloodiii) Endocardium: Epithelial tissue providing smooth surface for blood flowiv) Myocardium: Muscle tissue allowing for contractionv) Nervous tissue: Receives signals to control heart ratevi) Connective tissue: Protects and encases heart

vii) Breastbone: Protects heart from fontviii) Spine: Protects heart from behind

2) Veins: Carry blood to the heart

3) Arteries: Carry blood away from the heart.

Get diagrams.4) Blood:i) Plasma: In total 55% of bloods constitution, made of 90% water, 10% salt, proteins andhormonesii) Red blood cell (erythrocyte): In total 45% of bloods constitution, produced in bone marrow,

stored in spleen and carries oxygen to tissues via haemoglobin; possesses a biconcave shapeto maximize surface area for oxygen transfer and to allow for easy flow through blood vesselsiii) White blood cell (leukocyte): In total less than 1% of bloods constitution, fights infection;possesses an anamoeboid shape.

iiia) B-cells: Recognize invadersiiib) Macrophages: Kill invaders

iv) Platelets (thrombocytes): Clot blood

Describe the phases of circulation.1) Pulmonary circuiti) Deoxygenated blood enters right atriumii) Blood flows from right atrium to right ventricle through right atriovetricular (tricuspid) valve,

which prevents the backflow of deoxygenated blood into the atrium.iii) Blood is passed from right ventricle through pulmonary semilunar valve to the two pulmonaryarteries which carry it to the lungsiv) Blood travels through lung capillaries and becomes oxygenatedv) Oxygenated blood returns to the left atrium of the heart through four pulmonary veinsvi) Blood enters the left ventricle through the left atrioventricular (bicuspid) valce2) Systemic circuiti) Oxygenated blood leaves the left ventricle through the aortic semilunar valve and enters theaortaii) Aorta brances into smaller vessels and transports the blood to the whole bodyiii) Desoxygenated blood returns to the right atrium of the heart, brought from the upper body bysuperior vena cava and from the lower body by the inferior vena cava

Section 11.5 Coronary Artery DiseaseSection 11.6 Imaging: Looking Through the Body

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