HUGHES BIOLOGY



Brief Topic ReviewScientific MethodKey Terms:Hypothesis- A proposed explanation for a problem that can be tested using the scientific methodObservation- Information found using the five sensesInference- An educated guess made using evidence and reasoningExperimental Group- The group in an experiment receiving the treatmentControl Group- The group that does not receive the treatment in the experiment; it is to be used for comparison Independent Variable- What the researcher manipulatesDependent Variable- “Depends” on the independent variable and is measured in the endSteps of the Scientific Method:Make observations/ State the problem Gather informationState the hypothesisConduct experimentCollect dataState conclusionRepeat the experiment many times to increase the reliability of the dataAdditional Things to KnowIndependent variable is plotted on the x-axis on a graph and the dependent variable is plotted on the y-axisFamiliarize yourself with parts of a microscope (view diagram below)Know lab safety procedures such as using goggles, no eating in the lab, tie back hair, do not put a stopper into a test tube you are heating, etc. Life Functions/HomeostasisEight Life Functions: Transport- Absorption and distribution of materials throughout an organismExcretion- The removal of cellular waste products from an organism (Ex: urea and carbon dioxide)Nutrition- Obtaining materials from the environment and breaking them down for further use (Ex: ingestion, digestion, and egestion)Growth- Increasing in cell size or numberReproduction- Production of a new individualRegulation- Control and coordination of an organism’s internal environment through external reactions (Ex: Shivering)Homeostasis:The process by which an organism maintains stable internal conditions or dynamic equilibrium CellsCell Theory:Important ScientistAnton Von Leeuwenhoek- Creator of the first microscopeRobert Hooke- Used one of the first microscopes to look at a slice of cork and saw thousands of chambers he called cellsCell Theory All living things are composed of cellsCells are the basic unit of structure and function in living thingsNew cells arise from pre-existing cellsExceptions to the TheoryViruses reproduce themselves inside of organisms, but are not cellsChloroplast and mitochondria have their own DNA and duplicate themselvesFirst cell must have arisen from non-cellular matterCell Organelles:Familiarize yourself with the parts and their functions (view diagrams below)Plant Cells Only: Cell Wall and Chloroplast Animal Cells Only: Centrioles Transport:Osmosis- Water moving from an area of high concentration to an area of low concentrationSimple Diffusion (Passive Transport)- Molecule movement from an area of high to low concentrationFacilitated Diffusion- Diffusion through protein channels; no energy requiredActive Transport- Molecule movement from low to high regions of concentrationCan pass through membrane: Gases, water, simple sugar, amino acid--Cannot pass: starch, proteinIsotonic- The rate of osmosis in and out of the cell is the sameHypotonic- Lower water concentration inside the cell; higher concentration outside the cellHypertonic- Higher water concentration inside the cell; lower concentration outside the cellBiochemistryKey Terms:Element- A simple substance that could not be broken down further (Common elements- carbon, hydrogen, oxygen, nitrogen)Compound- Two or more elements combinedEnzymes- Special protein which regulates the rate of chemical reactions as known as organic catalyst Inorganic v. Organic:Organic Compound- Contains carbon and hydrogen together (Ex: Glucose)Inorganic Compound- Do not contain carbon and hydrogen together (Ex: Carbon Dioxide)Enzyme Substrate Complex: Enzymes associates with its substance whose rate of reaction it’s going to affect (substrate). When the reaction is complete, the enzyme and the product separate.Photosynthesis/RespirationATP (Adenosine Triphosphate): Organic molecule; energy used by all. It is attained by breaking high-energy bonds between the last two phosphates in ATP. ATP is made during the process of cellular respiration.Cellular Respiration: A series of controlled reactions where glucose is broken down to release energy.Types of RespirationAerobic Respiration- Required for oxygen; occurs in the mitochondria; 36 ATP are produced; occurs in animals and plants.Anaerobic Respiration (Fermentation)- Occurs in the cytoplasm; produces two ATP; occurs in some bacteria and yeast. Lactic Acid (Glucose→ Lactic Acid + 2 ATP)- Can occur in human muscle cells and some bacteria.Alcoholic Fermentation (Glucose→ Alcohol + CO2 + 2 ATP)- Performed by yeast and certain bacteriaLeaf Structure: Photosynthesis: The process by which autotrophs use energy from the sun to convert water and carbon dioxide into oxygen and high-energy carbohydrates. It is done in the chloroplast.Light Dependent Reaction: Requires direct involvement with light and absorbing light pigment; use the energy from the sunlight to produce ATP; takes place in the thylakoids; water is required and oxygen is released.Light Independent Reactions: ATP is used to produce high energy sugars from carbon dioxide; no light is required; take place in the stroma.Human SystemsDigestive System- Process the changes food into a form that can be by your body cells.Circulatory System- The system that circulates blood and lymph through the body. Immune System- A series of defenses that involve non-specific and specific attacks on disease causing agents (pathogen). Respiratory System- The process that brings oxygen in the air into your lungs and moves oxygen and through your body. This is how gas exchange occurs.Nervous System- Controls and coordinates functions throughout the body; pertaining to the brain.Endocrine System- Regulates, coordinates, and controls your body functions using hormones.Reproductive System- The system where the gametes unite to produce offspring. Asexual Reproduction/Mitosis/MeiosisAsexual Reproduction:Regeneration- The development of a new organism from a piece of a existing organism.Vegetative Propagation- New plants develop from roots, stems, or leaves of parent plants.Sporulation- Development of a new individual under favorable conditions of temperature and moisture.Budding- Unequal division of the cytoplasm Binary Fission- Equal division of the nucleus and cytoplasmMitosis: An orderly series of complex changes in the nucleus. Involves the exact duplication of the complete set of chromosomes and the separation of these chromosomes into two identical sets of chromosomes. Occurs in asexual reproduction.Meiosis: A type of cell division that results in four daughter cells each with half the number of chromosomes of the parent cell, as in the production of gametes and plant spores.GeneticsDNA (Deoxyribonucleic Acid): Genetic material in the chromosomes; found in the cell nucleus; composed of nucleotides. The nitrogenous bases molecules in a DNA molecule are adenine which pairs with thymine and guanine which pairs with cytosine. Scientist Watson and Crick modeled DNA as a double helix. RNA (Ribonucleic Acid): Single stranded; Uracil replaces thymine; can leave the nucleusProteins- Chains of amino acids connected by peptide bonds Protein Synthesis: Two step process- Transcription and translationMutations: Changes in the DNA sequence that affect genetic information. Point Mutation- Mutation that affects one nucleotide (single point in DNA)Substitution- One nucleotide replacedFrame Shift MutationsInsertion- Addition of an addition nucleotide Deletion- Removal of a nucleotideMutations occur during meiosis or can occur due to UV light, x-rays, insecticides, etc.Mutations are passed on through gametesChromosomal Mutations:Translocation- One piece of a chromosome is transferred to another chromosomeDuplication- Part of a chromosome was copiedDeletion-Part of a chromosome was removedInversion- A chromosome is broken then rearranged Nondisjunction- Chromosomes fail to separate (down syndrome)Ways to Detect Genetic Disorders:Karyotyping- Enlarged photograph of paired homologous chromosomes from a cellScreening- Chemical analysis of body fluids such as blood and urineAmniocentesis- Removal of amniotic fluid for chemical analysisGene Expression: The environment influences which genes are expressed (Ex: Factors such as temperature with the Himilayan rabbit)BiotechnologySelective Breeding- Crossing organisms with desired traits in order to pass these traits onto the next generation of offspring (Inbreeding and hybridization)Cloning- Creating an exact copy of an organism (Dolly the Sheep-1996)Recombinant DNA/ Genetic Engineering- The transfer of genetic material of one organism into another. Bacterial cells are able to synthesize substances such as insulin and growth hormone when human genes are inserted into them.Gel Electrophoresis- A method used to separate fragments of DNA in order to compare them (used for crimes, paternity test, taxonomy, and evolutionary biology)EvolutionEvolution- The process of gradual slow change through time Theories of Evolution:Lamarck- Offspring inherit acquired traits (baby giraffes will be born with long necks if their parents stretch their neck muscles)Weismann- Disproved Lamarck using an experiment where he cut off mice’s tails to show their offspring will still be born with a tail.Darwin- “Survival of the Fittest”: Organisms will adapt to their environment, and those who are better suited will survive and reproduce successfully.Resistance:Pesticides- Pesticide resistant insects will survive and reproduce causing population increaseAntibiotics- Antibiotic resistant bacteria will survive and reproduce causing population increase Natural Selection:Overproduction- Increased birth rateCompetition- Organisms compete for limited resources such as food, space and waterVariation- Different traits make some organisms better adaptedSurvival of the Fittest- Favorable traits lead to survivalReproduction- Parents pass on favorable traits to offspringEcologyEcology- The study of the relationships between organisms and their physical environmentLevels of Organization (highest→lowest):Biosphere- A portion of earth where many complex ecosystems existBiome- Group of ecosystems in the same climateEcosystem- Collect of biotic (living) and abiotic (non-living) factors living together with a constant source of energy and recycling of materials. Energy does NOT get recycled.3324225304800Community- Groups of populations in one defined areaPopulation- Group of organisms in the same species living in the same areaSpecies- Group of individuals so similar they can reproduceOrganism- An individualTypes of OrganismsProducer (Autotrophs)- Capture solar energy to make their own foodConsumer (Heterotrophs)- Must obtain energy from other organismsHerbivores- Only eat autotrophs such as plants and leavesCarnivore- Only eat animalsPredator- Kills and eats preyPrey- Killed by predatorScavenger- Eats dead animals that they did not kill themselves Omnivores- Feeds on producers and consumersDecomposers- Obtains nutrients from decaying organisms and recycles nutrients back into the earthFood Chains: One chain of energy Food Webs: All the food chains in an ecosystem connectedEnergy Pyramid: Model of the energy flow in a communityLimiting Factor: Factors that cause population growth to decreaseCarrying Capacity: When an environment reaches the maximum number of organisms it can hold→Symbiotic RelationshipsMutualism- Both organisms benefit Commensalism- One organism benefits and the other is unharmedParasitism- The parasite benefits while the host is harmedBiodiversity: A variety of different species and ecosystems Ecological Succession: The series of changes by which one habitat changes another Material Cycles: Water cycle, carbon oxygen cycle, and nitrogen cycleHuman Impact Negative Impact:Deforestation- Cutting down trees leads to habitat destruction, less oxygen, more carbon dioxide, less biodiversity, etc.Overhunting / Overharvesting- Removal of organisms directly from the environmentExploitation of Wildlife- Poaching species causing endangerment and extinctionInvasive Non-Native Species- These species disrupt food webs and have no natural predators. They are imported by pet trade, attached to ships and on plants. (Ex: Asian Long Horned Beetle and Zebra Mussels)Water Pollution- Poisonous chemicals are dumped into waterways such as PCBs.Air Pollution- Burning of fossil fuels causes acidic pH that harms plants, global warming, and smogGlobal Atmospheric Change- Greenhouse Gases such as carbon dioxide are trapped in the atmosphere causing global warming Ozone Depletion- caused by overuse of CFC’s, more UV radiation exposure increase in skin cancer ................
................

In order to avoid copyright disputes, this page is only a partial summary.

Google Online Preview   Download