IB Biology 1.5 Latest Version Already Graded A

IB Biology 1.5 Latest Version Already Graded A Endosymbiotic theory a theory that some eukaryotic organelles, such as mitochondria and chloroplasts, originated as free-living prokaryotes that invaded primitive eukaryotic cells. Allowed growth of smaller cells in a cytoplasm, through endocytosis, and the rapid replication they could persist indefinitely inside the large cells. It also states that mitochondria were once free living prokaryotic organisms that had developed the process of aerobic cell respiration and the previously mentioned process persisted so that mitochondria are inside the eukaryotic cells today. Organelles that are found in eukaryotic cell indicates that they have features that they used to exist in their own right. Genetic code a nearly universal sequence of nucleotides in DNA that determines the specific amino acid sequence in the synthesis of proteins. Louis Pasteur French scientist that proved, among other things, that the emergent growth of bacteria in nutrient broths is due to biogenesis, not spontaneous generation. Spontaneous generation old theory that believed in the formation of living organisms from non-living matter. Sterilization technique used for the elimination of microbiological organisms to achieve a sterile microbial environment. Evidence from Pasteur experiment refuted idea of spontaneous generation. Under favourable conditions, the broth that was inside the flasks was in contact with air which it had been suggested was needed for spontaneous generation, yet no spontaneous generation occurred. It shows that the glass swan necks prevented organisms from air getting into the broth or other liquids and that no organisms appeared spontaneously. Three parts of cell theory 1. All organisms are composed of one or more cells 2. All cells come from pre-existing cells 3. Cells are the basis of life Evidence that cells can only be formed by pre-existing cells -No mechanism has been found for producing cells from simpler subunits and cells are highly complex -All known examples of growth are the result of cell division -Viruses are produced from simpler subunits, but do not consist of cells, they can only be produced inside the host cells that they have infected. -Genetic code is universal each of the 64 combinations of 3 DNA bases produces the same amino acid in translation, regardless of organism Non-living synthesis of simple organic molecules (evidence for