IB Biology syllabus definitions Essays - Classical Genetics

IB Biology syllabus definitions Essays - Classical Genetics IB Biology syllabus definitions * Definition given in IB Biology syllabus TOPICWORDDEFINITION Topic 1: CellsOrganelleA discrete structure within a cell, with a specific function.* TissueA group of cells similar to each other, along with their associated intercellular substances, which perform the same function within a multicellular organism. OrganA group of tissues which work together as a single unit to perform a particular function within a multicellular organism. Organ systemA group of organs, vessels, glands, other tissues, and/or pathways which work together to perform a body function within a multicellular organism. Diffusion The passive movement of molecules from a region of high concentration to a region of low concentration. OsmosisThe passive movement of water molecules, across a partially permeable membrane, from a region of lower solute concentration to a region of higher solute concentration.* Topic 2: The Chemistry of LifeOrganicCompounds containing carbon that are found in living organisms (except hydrogencarbonates, carbonates and oxides of carbon).* EnzymeProteins that act as biological catalysts, speeding the rate at which biochemical reactions proceed but not altering the direction or nature of the reactions. Active siteA specific region of an enzyme where a substrate binds and catalysis takes place. DenaturationA structural change in a protein that results in a loss (usually permanent) of its biological properties. Refer only to heat and pH as agents.* DegenerateHaving more than one base triplet to code for one amino acid.* UniversalFound in all living organisms.* Cell respirationControlled release of energy in the form of ATP from organic compounds in cells.* TOPICWORDDEFINITION Topic 3: GeneticsGeneA heritable factor that controls a specific characteristic. (The differences between structural genes, regulator genes and genes coding for tRNA and rRNA are not expected at SL).* AlleleOne specific form of a gene, differing from other alleles by one or a few bases only and occupying the same gene locus as other alleles of the gene.* GenomeThe whole of the genetic information of an organism.* Gene mutationA change in the base sequence of a gene on DNA. This could be by substitution, deletion, or insertion of a base or bases. The terms point mutation or frameshift mutation will not be used. Homologous chromosomesA pair of chromosomes containing the same linear gene sequences, each derived from one parent. GenotypeThe alleles possessed by an organism.* PhenotypeThe characteristics of an organism.* Dominant alleleAn allele that has the same effect on the phenotype whether it is present in the homozygous or heterozygous state.* Dominant alleles mask the effects of recessive alleles. Recessive alleleAn allele that only has an effect on the phenotype when present in the homozygous state.* Codominant allelesPairs of alleles that both affect the phenotype when present in a heterozygote. (The terms incomplete and partial will no longer be used.)* LocusThe particular position on homologous chromosomes of a gene.* HomozygousHaving two identical alleles of a gene.* HeterozygousHaving two different alleles of a gene.* CarrierAn individual that has a recessive allele of a gene that does not have an effect on their phenotype.* Test crossTesting a suspected heterozygote by crossing it with a known homozygous recessive. (The term backcross is no longer used.)* Sex linkageGenes found on sex chromosomes (X and Y chromosomes) are said to be sex linked. Genetic screeningTesting an individual for the presence or absence of a gene.* CloneA group of genetically identical organisms or a group of cells artificially derived from a single parent cell.* TOPICWORDDEFINITION Topic 4: Ecology and EvolutionEcologyThe study of relationships between living organisms and between organisms and their environment.* EcosystemA community and its abiotic environment.* PopulationA group of organisms of the same species who live in the same area at the same time.* CommunityA group of populations living and interacting with each other in an area.* SpeciesA group of organisms which can interbreed and produce fertile offspring.* HabitatThe environment in which a species normally lives or the location of a living organism.* Autotroph (producer)An organism that fixes chemical energy in the form of organic molecules; it "makes its own food" and does not require previously formed organic materials from the environment; e.g. photoautotroph, chemoautotroph. Heterotroph (consumer)An organism that requires chemical energy from already formed organic molecules. DetritivoreAnimal that consumes decomposing organic particles, deriving nutrition primarily from microbes on the particles. Saprotroph (decomposer)Organism that feeds by secreting digestive enzymes onto its food source and absorbing the products of digestion. Fungi and bacteria are examples. Trophic levelStage in a food chain or web leading from primary producers (lowest trophic level) through primary consumers (herbivores) to secondary and tertiary

What Is the Platt Amendment Definition and Significance

What Is the Platt Amendment Definition and Significance SAT / ACT Prep Online Guides and Tips In 1898, the US was fighting the Spanish-American War and occupying Cuba as part of its involvement in maintaining the island’s newfound independence. Once the war was over, the US still wanted to maintain influence in Cuba. In order to achieve this, the Platt Amendment was passed. Read this guide to learn what the Platt Amendment includes, why it was created, what important dates are associated with it, and how its impacts live on today, including how it led to the creation of Guantanamo Bay. What Is the Platt Amendment? In simplest terms, the Platt Amendment was a treaty between the United States and Cuba that established guidelines for US-Cuban relations. The US wanted to maintain influence in Cuba to protect its interests there, but Cubans were wary of being under the control of another foreign power after recently gaining independence from Spain. The Platt Amendment was an attempt to appease both countries. The Platt Amendment set conditions under which the US would end its military occupation of Cuba but also granted the US the right to involve itself in Cuban affairs in order to protect Cuban independence. The Platt Amendment was drafted by Elihu Root, who was Secretary of State at the time, and in 1901 it was presented to the Senate by Senator Orville Platt of Connecticut as a rider attached to the Army Appropriations Bill. (Riders are sometimes also referred to as amendments, which is why it is called the Platt Amendment.) The Platt Amendment placed some pretty stringent restrictions on Cuba. It gave the United States pretty much unlimited ability to intervene in any Cuban affair for the purpose of preserving Cuban independence, prevented Cuba from transferring any of its land to any country other than the United States, limited Cuba’s right to negotiate treaties, gave the US rights to a naval base in Cuba (what is now Guantanamo Bay). It was reluctantly accepted by Cuba, who amended their Constitution to include it. There were seven articles in the Platt Amendment, and the Cuban government had to agree to all of them before the US withdrew its troops from the island and recognized Cuban sovereignty. Here are the articles of the Platt Amendment: Article I. The Government of Cuba shall never enter into any treaty or other compact with any foreign power or powers which will impair or tend to impair the independence of Cuba, nor in any manner authorize or permit any foreign power or powers to obtain by colonization or for military or naval purposes, or otherwise, lodgment in or control over any portion of said island. Article II. The Government of Cuba shall not assume or contract any public debt to pay the interest upon which, and to make reasonable sinking-fund provision for the ultimate discharge of which, the ordinary revenues of the Island of Cuba, after defraying the current expenses of the Government, shall be inadequate. Article III. The Government of Cuba consents that the United States may exercise the right to intervene for the preservation of Cuban independence, the maintenance of a government adequate for the protection of life, property, and individual liberty, and for discharging the obligations with respect to Cuba imposed by the Treaty of Paris on the United States, now to be assumed and undertaken by the Government of Cuba. . . . Article V. The Government of Cuba will execute, and, as far as necessary, extend the plans already devised, or other plans to be mutually agreed upon, for the sanitation of the cities of the island, to the end that a recurrence of epidemic and infectious diseases may be prevented, thereby assuring protection to the people and commerce of Cuba, as well as to the commerce of the Southern ports of the United States and the people residing therein.... Article VII. To enable the United States to maintain the independence of Cuba, and to protect the people thereof, as well as for its own defense, the Government of Cuba will sell or lease to the United States lands necessary for coaling or naval stations, at certain specified points, to be agreed upon with the president of the United States. What Led to the Creation of the Platt Amendment? The Platt Amendment came about as a result of the Spanish-American War, which occurred in 1898. During the roughly four months that the war lasted, the United States had a large military presence in Cuba, which it was ready to use to protect the US against Spanish attacks and protect US economic interests in Cuba. The day before the US entered the Spanish-American War, the Teller Amendment was passed by Congress. President William McKinley gave a speech asking Congress to allow the US to use its naval and military forces to help Cuba achieve independence, and Congress agreed but also passed the Teller Amendment, which placed limits on the US’s involvement. The Teller Amendment stated that the US couldn’t annex Cuba. Instead, the US had to help Cuba achieve stable independence, then withdraw its troops from the island once that had been achieved. This assuaged Congressional fears that President McKinley was hoping to annex Cuba. However, three years after the Spanish-American War was over and Cuba was independent, the US still had troops in Cuba. The US didn’t want to put its military and economic interests at risk by having Cuba descend into chaos during self-rule or be conquered by another foreign country. They decided to maintain a strong role in Cuban affairs until they believed their interests would be safe. Because of the Teller Amendment (which basically said the US had to help Cuba achieve independence and then leave), the Platt Amendment was drafted as a way to ensure the US could maintain a degree of control over Cuba until they were certain the country was stable and their interests would be protected. Key Dates for the Platt Amendment Below are all the key dates you need to know for events that happened before, during, and after the Platt Amendment was signed. February 24th, 1895- February 15th, 1898: The Cuban War of Independence is fought between Cuba and Spain. The final months escalate into the Spanish-American war. February 15th, 1898: The American battleship USS Maine, which was docked in Havana, explodes under mysterious circumstances, killing 258 people. The US blames Spain for the explosion which leads to the Spanish-American War. April 20th, 1898: The Teller Amendment is passed. April 21st - August 13th, 1898: The Spanish-American War is fought between Spain and the United States December 10th, 1898: The Treaty of Paris is signed. Spain agrees to grant independence to Cuba, and cedes the Philippines, Guam, and Puerto Rico the United States. March 2nd, 1901: The Platt Amendment is passed. December 25th, 1901: Cuba amends its constitution to include the entire Platt Amendment May 22nd, 1903: Cuba and the US agree to the Cuban-American Treaty of Relations of 1903. Among other things, this treaty allows the US to intervene in Cuban affairs and lease land for naval bases on the island. September 1906 - February 1909: Second Occupation of Cuba. The Cuban-American Treaty of Relations of 1903 is used to justify US military forces occupying Cuba in order to protect American economic interests and establish a new Cuban government. May 29th, 1934: As part of FDR’s Good Neighbor Policy, the Cuban-American Treaty of Relations of 1934 is signed, repealing most of the Platt Amendment (everything except US right to a naval base in Cuba). 1940: The Platt Amendment is eliminated from the new Cuban constitution during the Cuban Constitutional Convention of 1940. What Are the Lasting Effects of the Platt Amendment? The Cuban government was very reluctant to add the Platt Amendment to their constitution, as they had just become independent and didn’t want to be controlled by another foreign power. Even though it was eventually ratified, it caused a lot of resentment among Cubans towards America. Many historians also believe that the Platt Amendment actually ended up causing more instability in Cuba, including contributing to the Cuban Revolution of the 1950s. The Platt Amendment remained in effect until 1934, when US President Franklin Delano Roosevelt’s Good Neighbor Policy repealed the majority of the amendment in response to a surge in Cuban resentment. However, one stipulation of the Platt Amendment remained: the US was allowed to continue operating its naval base Guantanamo Bay. The Good Neighbor Policy stated that the US had the right to operate its naval base "until the two contracting parties agree to the modification or abrogation of the stipulations of the agreement in regard to the lease to the United States of America for coaling and naval stations†¦Ã¢â‚¬  Because the US hasn’t agreed to any modifications, , Guantanamo Bay remains open to this day and has been a major factor in shaping modern Cuban-American relations. Summary: Platt Amendment APUSH The Platt Amendment was one of the most important events in Cuba-US relations. A simple Platt Amendment definition is that it an amendment passed in 1901 that provided guidelines that allowed the US to maintain influence in Cuba after Cuba achieved independence. What did the Platt Amendment do? It gave the US the right to have a naval base in Cuba, intervene in Cuban affairs, and control Cuba’s agreements with other countries, among other things. Although the Platt amendment was created to protect US interests in Cuba, it was widely resented in Cuba and was nearly completed repealed in 1934, although the US naval base Guantanamo Bay is still in operation in Cuba. What's Next? Writing a research paper for school but not sure what to write about?Our guide to research paper topics has over 100 topics in ten categories so you can be sure to find the perfect topic for you. Did you know that water has a very special density? Check out our guide to learn what the density of water is and how the density can change. 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