Evolution and Classification of Life

• Evolution - change in the characteristics of biological populations over successive generations
• Darwin's Theory of Evolution by Natural Selection - species evolve through natural selection, which is driven by competition between individuals to survive and reproduce.
• Overproduction - higher demand than resource
• Struggle of Life - competition for food, water, and mates.
• Survival of the Fittest - develop adaptive characteristics that enable them to survive the struggle for existence (traits = benefits)
• Variation - the differences between individuals in a population, which can be used to identify the presence of a particular gene
• Heredity - mechanism the allows passing of adaptive characteristics from parent to offspring
• Fossil records - The record of past life forms preserved in rocks.
• Embryological characteristics - show different organisms are alike in the early stages of life but eventually differentiate due to maturation
• Homologous structures - support divergent evolution, descended organisms from the same ancestors have structures that are similar form, but different function.
• Analogous structures - descended organisms from very distant ancestors but have developed structures that are similar in function
• Vestigial strctures - descended organisms from an ancestor that makes full of use of those structures, but lost parts in the new habitat
• earliest cells appeared at about 3.5 million years ago and from the Kingdom Monera.
• Cyanobacteria - first to utilize sunlight and photosynthesis to capture energy and produce an important by-product, oxygen.
• Endosymbiotic theory (symbiogenesis) - the theory that the mitochondria and chloroplasts evolved from symbiotic relationships between bacteria and algae. Explains why they have their own DNA
• Taxonomy - study of biological classification that involves grouping of organisms based on shared characteristics
• Binomial nomenclature - the naming of organisms using the genus and species name
• Kingdom Monera - prokaryotic and unicellular organisms that reproduce asexually
• Subkingdom Archaebacteria (extremophiles) - ancient procaryotic bacteria that can tolerate harsh environment.
• Subkingdom Eubacteria - true bacteria
• Kingdom Protista - eukaryotes that are either unicellular or simple multicellular that lack a true nucleus and are not classified as plants, animals, or fungi.
• Algae - photosynthetic protists but have different cells and organs from plants
• Protozoans - unicellular & heterotrophic organisms
• Kingdom Fungi - fungi that are eukaryotic, heterotrophic organisms which reproduce by spores and are usually saprophytic
• Kingdom Plantae - multicellular, autrophic organisms that have chlorophyll and sexually reproduce
• KIngdom Animalia - multicelluar, heterotrophic eukaryotes and are usually motile
• Non-vascular plants (atracheophytes) - lack true roots, stems, and leaves
• Mosses - have a thin, fibrous root system, and are found in moist areas
• Lichens - A symbiotic relationship between a fungus and an alga.
• Vascular plants (Tracheophytes) - have vascular tissue and are multicellular. Transport water and food throughout the organism
• Seedless vascular plants - produce spores by mitosis, not by meiosis
• Seeded vascular plants - produces seeds for reproduction
• Gymnosperms - cone-bearing plants
• Angiosperms - flower-bearing plants
• Monocots - single-seed cotyledon
• Dicots - double-seed cotyledon
• Symmetry - shows an orderly structure in an organism's body and arrangement of body parts
• Bilateral symmetry - the body is symmetrical on both sides of the midline. (mirror images of each other) (ex. lobster, dog)
• Radial symmetry - the body is symmetrical around a central axis, such as a circle or a line. (Ex. jellyfish)
• Irregular symmetry - A shape that does not have a regular pattern of repeating shapes. (Ex. sponges)