Tuesday, March 10, 2020

Essay on Bio Notes

Essay on Bio Notes Essay on Bio Notes Vocab Genetic diversity: the level of biodiversity, refers to the total number of genetic characteristics in the genetic makeup of a species Species diversity: is the effective number of different species that are represented in a collection of individuals Structural Diversity: is the divisions in a community that result from having many different physical characteristics Protista: free-living or colonial organisms with diverse nutritional and reproductive modes, diverse group of eukaryotic microorganisms Bacteria: a member of a large group of unicellular microorganisms lacking organelles and an organized nucleus, including some that can cause disease, consist of prokaryotic microorganisms Fungi: an organism of the kingdom Fungi lacking chlorophyll and feeding on organic matter; ranging from unicellular or multicellular organisms Binomial nomenclature: the system of nomenclature using two terms, the first one indicating the genus and the second the species Morphology: the form or structure of an organism or one of its parts Extinction: the state or process of a species, family, or larger group being or becoming extinct, no longer existing Natural selection: Theory by Darwin that organisms better adapted to their environment tend to survive and produce more offspring compared to other organisms. Main process which leads to evolution Phylogeny: branch of biology that studies how groups of organisms are related in terms of how they evolved. Speciation: The formation of new and distinct species in the course of evolution Niche: a position or role taken by a kind of organism within its community Mutation: the changing of the structure of a gene, resulting in a variant form that may be transmitted to subsequent generations, caused by the alteration of single base units in DNA, or the deletion, insertion, or rearrangement of larger sections of genes or chromosomes Mimicry: the close external resemblance of an animal or plant (or part of one) to another animal, plant, or inanimate object Adaptation: a change by which an organism or species becomes better suited to its environment Survival of the fittest: as the environment changes, those members of a species who, by accidental genetic variation, happen to have traits best fitted to the new environment are most likely to survive long enough to generate offspring Haploid: when an organism has a single set of unpaired chromosomes Diploid: when an organism contains two complete sets of chromosomes, one from each parent Spindle: a slender mass of microtubules formed when a cell divides. At metaphase, the chromosomes become attached to it by their centromeres before being pulled toward its ends Synapsis: the fusion of chromosome pairs at the start of meiosis Gamete: a mature haploid male or female germ cell that is able to unite with another of the opposite sex in sexual reproduction to form a zygote Zygote: a diploid cell resulting from the fusion of two haploid gametes; a fertilized ovum Heterozygous: zygosity refers to the similarity of genes for a trait (inherited characteristic) in an organism. If both genes are different, the organism is heterozygous for that trait Homozygous: if both genes are the same, the organism is homozygous for the trait Allele: one of two or more alternative forms of a gene that arise by mutation and are found at the same place on a chromosome Plasmid: a genetic structure in a cell that can replicate independently of the chromosomes, typically a small circular DNA strand in the cytoplasm of a bacterium or protozoan. Plasmids are much used in the laboratory manipulation of genes Trisomy: a condition in which an extra copy of a chromosome is present in the cell nuclei, causing developmental abnormalities Non-disjunction: the failure of one or more pairs of homologous chromosomes or sister chromatids to separate normally during nuclear division, usually resulting in an abnormal