Pre-Lab Questions

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Rahul Shah

Period 1AP Bio

3/9/2011

A.P. Biology Review Outline

Key: Covered in Trimester I

Covered in Trimester II

Covered in Trimester III

I. Molecules and Cells: Cells are the structural and functional units of life; cellular processes arebased on physical and chemical changes.

A. Chemistry of Life (7%)

1. Water How do the unique chemical and physical properties of water make life on earth possible?

2. Organic molecules in organismsWhat is the role of carbon in the molecular diversity of life?How do cells synthesize and break down?How do structures of biologically important molecules (carbohydrates, lipids, proteins, nucleicacids) account for their functions?

3. Free energy changesHow do the laws of thermodynamics relate to the biochemical processes that provide energy toliving systems?

4. EnzymesHow do enzymes regulate the rate of chemical reactions?How does the specificity of an enzyme depend on its structure?How is the activity of an enzyme regulated?

B. Cells (10%)

1. Prokaryotic and eukaryotic cellsWhat are their similarities and differences?What are their evolutionary relationships?

2. MembranesWhat is the current model of the molecular architecture of membranes?How do variations in this structure account for functional differences among membranes?How does the structural organization of membranes provide for transport and recognition?What are various mechanisms by which substances cross membranes?

3. Subcellular organizationHow does compartmentalization organize a cell's functions?

How are the structures of the various subcellular organelles related to their functions?How do organelles function together in cellular processes?What factors limit cell size?

4. Cell cycle and its regulationHow does the cell cycle assure genetic continuity?How does mitosis allow for the even distribution of genetic information to new cells?What are the mechanisms of cytokinesis?How is the cell cycle regulated?How can aberrations in the cell cycle lead to tumor formation?

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Rahul Shah

Period 1AP Bio

3/9/2011

C. Cellular Energetics (8%)

1. Coupled reactions

What is the role of ATP in coupling the cell's anabolic and catabolic processes?How does chemiosmosis function in bioenergetics?

2. Fermentation and cellular respirationHow are organic molecules broken down by catabolic pathways?What is the role of oxygen in energy-yielding pathways?How do cells generate ATP in the absence of oxygen?

3. PhotosynthesisHow does photosynthesis convert light energy into chemical energy?How are the chemical products of the light-trapping reactions coupled to the synthesis of carbohydrates?What kinds of photosynthetic adaptations have evolved in response to different environmentalconditions?What interactions exist between photosynthesis and cellular respiration?

II. Heredity and Evolution: Hereditary events control the passage of structural and functionalinformation from one generation to the next.

A. Heredity (8%)

1. Meiosis and gametogenesisWhat features of meiosis are important in sexual reproduction? Meiosis allows to gametes tofrom and eventually become one. Essentially, it is allowing two genetic donors to createoffspring. The sexual role it plays allows for more diversity than asexual reproductionWhy is meiosis important in heredity? Meiosis is extremely important in heredity. It isdetrimental to allow the passing on of traits. There is a 50% chance that the offspring will be afemale or male depending on the chromosomes. Independent assortment and crossing over alsoplay a role to increase the variety of possible genetic possibilities….How is meiosis related to gametogenesis? Gametogenesis includes making the cell (like spermor egg) AND the meiosis function. For example, in males, gametogenesis includes the meiosiscomponent of making a sperm cell as well the process of making the sperm tail, etc…What are the similarities and differences between gametogenesis in animals and gametogenesisin plants? Gametogenesis in animals is the creation of sperm and egg and it also includesmeiosis. It is carried out in the gonads (testes in males and ovaries in women).The result of it is 4haploid gametes.

2. Eukaryotic chromosomesHow is genetic information organized in the eukaryotic chromosome? Genetic information isorganized quite uniquely in eukaryotic chromosomes. The double helix strands are originally longad stretched out in the form of chromosomes; however they can be compacted if they are wound

around the histones. Then, they become 30 mm fibers, then they become looped domains, andlast they become their most fully condensed form which is when they are scaffolding.How does this organization contribute to both continuity of and variability in the geneticinformation? This organization can help to protect the DNA. A is only bonded to T and C is alwaysbounded to G as the width of the DNA strand must equal to three and this combination of nucleicacids always adds up to three. A-T forms 2 hydrogen bonds while C-G forms 3. These are safetymechanisms so the DNA doesn’t mutate. Independent assortment (increases possibilities of dom-recessive combinations with different setups of the chromosomes), crossing over (parts of chromosome break apart and cross over with another chromosome where the compatible parthas also broken off), and sexual reproduction (each organism participating gives only 50% of

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Rahul Shah

Period 1AP Bio

3/9/2011

their chromosomes so there are a huge amount of possibilities) serve to contribute to variabilityof our genetic information.

3. Inheritance patterns

How did Mendel's work lay the foundation of modern genetics? Heredity first began to beunderstood due to the work of Austrian monk and botanist Gregor Mendel (1822-1884), whodiscovered that hereditary factors determine all hereditary traits. Although Mendel was notrecognized for his work at the time, modern genetic science is solidly based on Mendel'sfindings. Experimenting with pea plants, Mendel noticed that the plants inherited traits in apredictable way. It was as though the pea plants had a pair of factors responsible for each trait.Even though he never actually saw them, Mendel was convinced that tiny independent unitsdetermined how an individual would develop. Until then, traits were thought to be passed onthrough a mixing of the mother and father's characteristics, much like a blending of two liquids.Mendel's laws of heredity were rediscovered in 1900, when they became vitally important tobiologists. Among other things, Mendel's laws established heredity as a combining of independent units, not a blending of two liquids. Danish geneticist Wilhelm Johannsen (1857-1927), a strong supporter of Mendel's theories, coined the term "gene" to replace the variety of terms used to describe hereditary factors. His definition of the gene led him to distinguishbetween genotype (an organism's genetic makeup) and phenotype (an organism's appearance).What are the principal patterns of inheritance? The Law of Segregation states that when anyindividual produces gametes, the copies of a gene separate so that each gamete receives onlyone copy. A gamete will receive one allele or the other. Mendel formulated this principle afterdiscovering another principle now known as Mendel's law of segregation. This principle statesthat the alleles for a trait separate when gametes are formed. These allele pairs are thenrandomly united at fertilization. Mendel arrived at this conclusion by performing monohybridcrosses. These were cross-pollination experiments with pea plants that differed in one trait, forexample pod color.

B. Molecular Genetics (9%)

1. RNA and DNA structure and functionHow do the structures of nucleic acids relate to their functions of information storage and proteinsynthesis? DNA is good for storing information for many reasons. The backbone that it has isbeneficial for keeping bases ordered. Also, the fact that it has 2 sides means that it can replicateboth sides at once, and it is more protective.What are the similarities and differences between prokaryotic and eukaryotic genomes? DNA isextremely long and extremely organized. It has a deoxyribose sugar and a phosphate backbonewhich when combined with its double helix shape helps prevent free radicals from damaging thenucleotides. DNA also has a guanine cap and a Poly A tail to help preserve DNA. Telomeres arealso present at the end of the DNA so that there is no erosion at the ends. RNA on the otherhand is single stranded, and small enough to leave the nucleus through the nucleic pores. RNAand DNA are essentially both made of DNA though, as the RNA is transcribed from DNA. Alsothey both have similar purposes and functions.

2. Gene regulationWhat are some mechanisms by which gene expression is regulated in prokaryotes andeukaryotes? In prokaryotes, an operon regulates protein synthesis as it is a series of self-regulating genes that works in concert. The promoter and operator within the operon controlgene expression. These segments overlap, and their interaction determines whether the processwill start and when it will stop. In eukaryotes, there are multiple gene-regulating mechanisms.Histone packing prevents the RNA polymerase from contacting the DNA, thus not allowing it tobe transcribed. DNA methylation also plays a role in regulating gene expression as it preventsthe genes from being expresses, DNA acetylation on the other hand encourages that gene(s) tobe expressed.

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Rahul Shah

Period 1AP Bio

3/9/2011

3. MutationIn what ways can genetic information be altered? Genetic info can be altered in many ways. Theorder of the DNA acids can be changed. At the nucleic levels, point mutations can occur like

substitutions (substituting once base for another), insertions (inserting a base into the order),deletions (…), and frame shifts (shifting the whole order to the L or R). At the level of nucleotidestrings, inversion, rearrangement, and duplication can occur. At the level of the entirechromosome, translocation (movement of gene to a chromosome)m fusion (2 chromosomescombine), fission (one chromosome splits), and duplication (can range from entire segment to anentire genome)What are some effects of these alterations? These alterations can have many effects. It can haveno effect, or it can mess up an organism completely and cause various other deformities anddiseases. Examples of structural chromosomal abnormalities include cri du chat syndrome. Cridu chat means "cat cry" in French. Children with this syndrome have an abnormally developedlarynx that makes their cry sound like the mewing of a cat in distress. They also have a smallhead, misshapen ears, and a rounded face, as well as other systemic defects. These childrenusually die in infancy. Cri du chat is caused by a deletion of a segment of DNA in chromosome 5.Also, sometimes these mutations can sometimes be favorable, like for an example, if abacterium somehow obtains a mutation that makes it resistant to an antibacterial drug (this isonly favorable for the bacteria not us obviously….)

4. Viral structure and replicationWhat is the structure of viruses? Viruses consist of strands of the genetic material nucleic acid,the basis of a genome, which is surrounded by a protein coat called a capsid. The capsidprotects the genome and gives the virus its shape. Viruses may be either helical or icosahedral.Some viruses display a combination of helical and icosahedral symmetry, known as complexsymmetry. The capsid is often subdivided into individual protein subunits called capsomeres. Theorganization of the capsomeres yields the symmetry of the virus. Animal viruses often form anenvelope around the capsid. This envelope is rich in proteins, lipids, and glycoprotein molecules.What are the major steps in viral reproduction? First the virus’s tail attaches itself to the host cellwhich will soon have the virus DNA. After this, the virus’ sheath penetrated the hosts cell wall

and injects the head of itself into the host cell. Lastly, the ivrions burst which then causes thecell to burst carrying huge amount of the virus cells that first infected it. There are two cycles,lytic and lysogenic… Look below…

How do viruses transfer genetic material between cells? The virus attaches itself onto the celland injects its DNA into the cell, causing the cell to make more viruses who then repeat thisprocess over and over. The DNA flows through the head and down the tail…

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Rahul Shah

Period 1AP Bio

3/9/2011

5. Nucleic acid technology and applicationsWhat are some current recombinant technologies? Inserting DNA into bacteria using viruses andother methods. Also, human insulin is able to be produced from bacterial cell which is a great

help for many.What are some practical applications of nucleic acid technology? DNA gels, mapping the humangenome, probes used to find specific sequences of DNA, using it to modify crops to grow morefood and be resistant to certain diseases and temperatures.What legal and ethical problems may arise from these applications? The two biggest problemsare containment (there have been many instances of supposedly controlled life forms escapinginto the wild and spreading their drastically altered DNA) and unintended consequences (lifeforms are complex and often changing one thing changes another). Two prototypical examplesof this are Star Link corn (which caused a national recall of all corn-related products and even sosome was consumed by humans before it was tested and determined safe) and Showa Denkotryptophan (the wildly popular nutritional supplement somehow killed seven people and causeda ban which lasts to this day).

C. Evolutionary Biology (9%)

1. Early evolution of lifeWhat are the current biological models for the origins of biological macromolecules? Atmosphereof earth chemically reducing in nature, electrical activity can then catalyze the creation of certain basic small molecules of life. BIG BANG theory (explosion created all the universe)What are the current models for the origins of prokaryotic and eukaryotic cells? Eukaryotic cellsevolved from prokaryotic cells through the ingestion of a "mitochondria-like" prokaryote byanother predatory prokaryote... It couldn't digest another prokaryotic cell that was similar to themitochondria found in eukaryotic cells and it lacked the enzymes to digest it, so the"mitochondria-like" prokaryote lived inside its captor, ultimately providing a significantadvantage in energy production.

2. (The oldest living prokaryotic cells found are approx. 3.5 billion years old, and the oldest living

eukaryotic cells found are approx. 1.4 billion years old.)3. Evidence for evolution

What types of evidence support an evolutionary view of life? The Fossil Record (increasinglycomplex organisms over time), catastrophism (after huge disaster, organism die and reset to thesimple form, and then we can see them again slowly evolve and change), extinctions.Comparative anatomy shows homologous and vestigial structure, biogeography shows thatsimilar organism came from similar places… Gradualism, punctuated equilibrium (mostreproducing species will remain rel. the same throughout their geographical history)…

4. Mechanisms of evolutionWhat is the role of natural selection in the process of evolution? Natural selection allowsorganism that are best fitted to the environment to survive and therefore, create offspring. Thisprocess insures that the species will progress toward a genetic build that favors the currentconditions and environment, which is, essentially, evolution

How are heredity and natural selection involved in the process of evolution? Natural selectionwas already spoken about above, but to recap, it favors organisms in a species that are bestadapted to their niche and habitat, therefore they reproduce, therefore, their “good” genes arepassed on to their offspring → evolution. As far as heredity, it is how the favorable genes fromthe parents transfer to the offspring, so without it, evolution cannot occur.What mechanisms account for speciation and macroevolution? Speciation and macroevolutionoccur when there is a split in the organisms (like a fissure forms), etc. For example allopatric,peripatric, parapatric, and sympatric. Although these are not all geographic, they still aremechanisms that account for speciation and macroevolution.

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Rahul Shah

Period 1AP Bio

3/9/2011

What different patterns of evolution have been identified and what mechanisms are responsiblefor each of these patterns?

1) Divergent evolution describes two or more species that evolved from a common ancestor.

2) Convergent evolution describes two or more unrelated species that have adopted similar adaptations to their environment.

3) Parallel evolution describes two or more species that have continued to evolve similar characteristics even after their divergence from a common ancestor.

4) Coevolution describes the evolution of one species in response to the evolution of another. Coevolution usuallyoccurs in a predator-prey relationship.

III. Organisms and Populations: The relationship of structure to function is a theme that is commonto all organisms; the interactions of organisms with their environment is the major theme in ecology.

A. Diversity of Organisms (8%)

1. Evolutionary patternsWhat are the major body plans of plants and animals?

2. Survey of the diversity of lifeWhat are representative organisms from the Monera, Fungi, and Protista?What are representative members of the major animal phyla and plant divisions?

3. Phylogenetic classificationWhat are the distinguishing characteristics of each group (kingdoms and the major phyla anddivisions of animals and plants)?

4. Evolutionary relationshipsWhat is some evidence that organisms are related to each other? The Strongest evidence thatorganisms are related to each other comes from the universal genetic code. All organisms speakthe same genetic language no matter their size or shape. Also, humans speak so manylanguages, but are all essentially the same beings. This proves that everything on earth evolvedfrom a single common ancestor that has the universal genetic ode within them.How do scientists study evolutionary relationships among organisms? Taxonomist use an eightlevel system to classify living things based on shared characteristics. Scientists also used sharedcharacteristics to hypothesize how closely related living things are. The more characteristics theorganisms share, the more closely related the organisms may be. For example, the platypus,brown bear, lion, and house cat are thought to be related because they share manycharacteristics. These animals have hair and mammary glands, so they are grouped together asmammals. But they can also be further classified into more-specific groups.How is this information used in classification of organisms?

B. Structure and Function of Plants and Animals (32%)Reproduction, growth, and development What patterns of reproduction and development are found in plants and animals and how are theyregulated?What is the adaptive significance of alternation of generations in the major groups of plants?

1. Both asexual and sexual reproduction occurs in the animal kingdom2. Diverse mechanisms of asexual reproduction enable animals to produce identical offspringrapidly.3. Reproductive cycles and patterns vary extensively among animals.

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Rahul Shah

Period 1AP Bio

3/9/2011

Mechanisms of Sexual Reproduction1. Internal and external fertilization depend upon mechanisms ensuring that mature spermencounter mature eggs of the same species.

2. Species with internal fertilization usually produce fewer zygotes but provide more parentalcare that species with external fertilzation.3. Complex reproductive strategies have evolved in many animal phyla.

1. Structural, physiological, and behavioral adaptationsHow does the organization of cells, tissues, and organs determine structure and function in plantand animal systems? Cells make up tissues witch make up organs. Their organization has aprofound impact on the structure and function of animal systems. Each organ, cell, and tissue isinterdependent on each other. For example, the heart requires the lounges to put air into theblood, and the kidney to clean and filter the blood. Cells are specialized; meaning only a part of their DNA is actually activated. They work together to form tissues which then work together toform organs. Each level is specialized, meaning they are put together to perform specificfunctions within an organism. For example, in humans, the kidney cleans the blood; however, it

doesn’t pump blood like the heart.How are structure and function related in the various organ systems? There are many differentorgan systems within the body. The circulatory system transports substances throughout thebody. The vascular tissue are the tubes that also transport blood, the respiratory system allowsgas exchange between the circulatory system and the external environment, the digestivesystem breaks apart large molecules in food until they are small enough t be absorbed into thecirculatory system to be eventually transported to cells. The endocrine system controls bodilysystem and helps us maintain homeostasis. The muscular system is stimulated by the nervoussystem to allow us to move and such. The skeletal system provides support and structure to thebody and protects vital organs. The reproductive system allows is to create offspring, theimmune system fights infections and prevents us from foreign substances; the lymphatic systemfilters substances through the blood. As one can see, these various organs are related in bothstructure and function, For example, the lymphatic system filters blood which is transported from

the circulatory system. The respiratory system puts the required gases into the blood which istransported by the circulatory system which is filtered by the lymphatic system. All thesefunctions are intertwined and serve one purpose: to allow the organism to have healthy,functional life.How do the organ systems of animals interact? They react in many ways. For example, thecirculatory system needs oxygen in the red blood cells to nurture the cells so they won’t die. If the respiratory system was not functioning, then oxygen could not be exchanged and the cells inthe body would die. If the air does not get to the brain and other vital organs then they wouldshut down and affect other systems and eventually the whole organism. Structure is extremelyspecialized because of tissues for organs which helps play its role in the system. If it did notwork, then again the whole would suffer.What adaptive features have contributed to the success of various plants and animals on land?

2. Response to the environment

What are the responses of plants and animals to environmental cues, and how do hormonesmediate them?

C. Ecology (10%)

1. Population dynamicsWhat models are useful in describing the growth of a population?How is population size regulated by abiotic and biotic factors?

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Rahul Shah

Period 1AP Bio

3/9/2011

2. Communities and ecosystemsHow is energy flow through an ecosystem related to trophic structure (trophic levels)?How do elements (e.g., carbon, nitrogen, phosphorus, sulfur, oxygen) cycle through ecosystems?

How do organisms affect the cycling of elements and water through the biosphere?How do biotic and abiotic factors affect community structure and ecosystem function?

3. Global issuesIn which ways are humans affecting biogeochemical cycles?

Key: Covered in Trimester I

Covered in Trimester II

Covered in Trimester III

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