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Big Idea 3: Living systems store, retrieve, transmit, and respond to information essential to life processes. How is it that all life uses the same 4 nucleotides in their DNA and RNA? How do those nucleotides “store” information”? What is the central dogma of DNA?
Need to know about Information
Basic Achievement Training:
High Achievement Training:
Need to know about Information
- A virus consists of a nucleic acid and a protein coat. Some even have a lipid envelope.
- Know the Frederick Griffith experiment concerning inheritance. The Avery, McCarty and, & Macleod experiment in that DNA was shown to be the hereditary molecule not proteins. Know Hershey & Chase experiment that refined the work of Avery and friends. Watson, Crick, Franklin, & Wilkins about DNA’s structure and X-Ray crystallography
- The way that RNA is copied is in the 5’ to 3’ direction and runs antiparallel to the other nucleic acids
- Silent mutations are that the amino acid stays the same with the mutation, nonsense changes the codon to a stop codon, and missense changes the amino acid for better or for worse to a different one.
- Genetic engineering is the direct manipulation of genetic information. It allows for direct control of gene expression and novel combinations of genetic information from different species.
- Gel Electrophoresis is the separation of DNA based on its size using an electrical field and a gel matrix. Smaller DNA molecules will move further and faster than larger ones. This technique is used to isolate specific genes within a larger sample of DNA or to visualize differences in DNA sequences.
- Mitosis produces two identical diploid daughter cells.
- Meiosis produces haploid cells in sexually reproducing organisms. Produces four genetically unique gametes with half of the normal amount of genetic material. This is what allows for variations within species.
- Crossing over occurs during prophase 1. Independent Assortment occurs during metaphase 1.
- Genotypes are the alleles that an organism has. Phenotypes are the traits an organism shows.
- Central Dogma- Term created by Francis Crick to explain how information flows in cells.
- Replication- The way DNA is copied; it starts with initiation and it starts at specific “origins”
- DNA Polymerase- Enzyme responsible for DNA synthesis
- Helicase- Opens the Helix, which causes strand separation.
- Primase- Puts down a small RNA primer, which is necessary for DNA polymerase to bind to the origin.
- Topoisomerase- Rotates the DNA to decrease torque (which would shred the helix)
- Anti-Parallel- DNA is anti-parallel; both strands have opposite 5’ to 3’ orientations (one is upside down compared to the other)
- Replication Fork- The point at which the two strands of DNA are separated to allow replication of each strand.
- Telomeres- The ends of eukaryotic chromosomes. They consist of a short, repeating DNA sequence.
- Telomerase- The enzyme responsible for replicating the ends of eukaryotic chromosomes. Uses a RNA template to add more telomere sequence during replication.
- The development of an organism is coordinated by sequential changes in gene expression.
- In order for an organism to develop properly, genes must be turned on and off at appropriate times.
- The interaction of an organism with external stimuli and the process of regulated gene expression results in cells, tissues, and organs becoming specialized.
- Common ancestry and convergent evolution are responsible for the similarities seen within homeostatic control systems.
- Interactions between environmental and internal signals are required to evoke a particular behavior within an organism.
- Plant responses are affected by internal and external signals. Such responses include phototropism (growth in response to light) and photoperiodism (flowering in response to periods of light and dark of specific length).
- Hox genes are a family of related genes that are responsible for the regulation of animal development.
- All open systems have feedback loops and are seen at all levels of organization within a living system.
- The different requirements of the environment that organisms occupy has driven divergence in homeostatic mechanisms.
- Behaviors can be inherited and adapted by natural selection.
- Apoptosis- “programmed cell death”- This is how we develop appendages such as fingers.
- Differentiation- During development, cells differentiate into many different cell types. This is accomplished by the expression of cell type-specific proteins.
- Operons- a unit made up of linked genes that is thought to regulate other genes responsible for protein synthesis.
- Negative feedback- any situation where the output of a process decreases the occurrence of that process. Regulatory in nature. Negative feedback maintains homeostasis of the system.
- Positive feedback- any situation where the output of a process increases the occurrence of that process. Amplifying in nature. Positive feedback causes transformation in the system.
- Respiration- Respiration must occur across a thin, moist, capillary-rich surface membrane. Aquatic animals have external respiratory membranes (skin, gills).
- Nitrogenous waste- (from protein and nucleic acid breakdown) must be excreted from the body. Different animals convert nitrogenous waste to different molecules.
- Types of Waste:
- Ammonia- the most toxic, and must be immediately diluted and excreted.
- Urea- less toxic, and does not need to be diluted as greatly, or excreted as quickly.
- Uric Acid- can be excreted as a solid.
- B-cells- a lymphocyte not processed by the thymus gland, and responsible for producing antibodies.
- T-cells- a lymphocyte of a type produced or processed by the thymus gland and actively participating in the immune response.
- Antigens- a toxin or other foreign substance that induces an immune response in the body, especially the production of antibodies.
Basic Achievement Training:
- Explain how the structural features of DNA and RNA allow heritable information to be replicated, stored, expressed, and transmitted to future generations.
- Explain how the steps in the cell cycle allow transmission of heritable information between generations and contribute to genetic diversity.
- Identify mathematical evidence that supports the roles of chromosomes and fertilization in the passage of traits from parent to offspring.
- Justify whether a given data set supports Mendelian inheritance.
- Using appropriate examples, explain how gene regulation allows for cell specialization and efficient cell function.
- Using an appropriate example, describe a signal transduction pathway mechanism that affects protein expression.
- Describe the basic processes by which a change in a DNA sequence results in a change in a peptide sequence.
- Describe two processes that increase genetic variation and explaining how genetic variation allows for natural selection within a population.
- Describe several mechanisms that result in increased genetic variation and rapid evolution of viruses.
- Propose scientific questions that address if there are shared mechanisms for cell-to-cell communication across evolutionary lines.
- Describe how both plants and animals use cell-to-cell communication for cellular processes using an appropriate example from each.
- Explain key features of models that illustrate how changes in a signal pathway can alter cellular responses.
- Describe how behavior is modified in response to external and internal cues for both animals and plants using appropriate examples from each.
- Describe how the nervous system detects external and internal stimuli and transmits signals along and between nerve cells.
High Achievement Training:
- Predict which features of DNA and RNA were necessary to allow the identification of DNA as the genetic material and justify how these features enable information to be replicated, stored, and expressed.
- Using at least two commonly used technologies, describe how humans manipulate heritable information and possible consequences.
- Justify the effects of a change in the cell cycle mitosis and/or meiosis will have on chromosome structure, gamete viability, genetic diversity, and evolution.
- Predict possible effects that alterations in the normal process of meiosis will have on the phenotypes of offspring compared to the normal situation and connect the outcomes to issues surrounding human genetic diseases.
- Apply mathematical routines to determine Mendelian patterns of inheritance provided by data sets, and, using appropriate examples, explain at the chromosome, cellular, and offspring (organism) levels why certain traits do or do not follow Mendel’s model of inheritance.
- Justify how various modes of gene regulation (positive and negative) can explain the differences seen at the cellular, organismal, and population level. Predict how changes in regulation will affect cellular functions.
- Using appropriate examples, predict how changes in signal transduction pathways will affect specific cellular processes and responses for both bacteria and eukaryotes.
- Predict how various types of change in a DNA sequence can alter a phenotype, and describe several using real-world examples.
- Justify how various molecular, cellular, and organismal processes in bacteria and eukaryotes increase genetic variation in a population and allow for natural selection.
- Using specific examples, justify how the life cycles of DNA and RNA viruses can contribute to rapid evolution of both the virus and the host.
- Justify how the mechanics of cell-to-cell communication support common lines of evolutionary descent. Pose scientific questions that test the justification rationale.
- Using appropriate examples from plants, animals, and bacteria, justify how the features of cell-to-cell contact and the use of chemical signals allow communication over short and long distances.
- Construct a model that illustrates how chemical signals can alter cellular responses. Predict the effects of changes in the signal pathway on cellular responses using appropriate examples.
- Justify how changes in internal or external clues affect the behavior of individuals and their interactions within a population and between related individuals.
- Describe how the animal nervous system’s biochemical, physiological, and structural components work together to respond to internal and/or external stimuli. Describe how changes within nerve cells and the nervous system produce responses to the stimuli.