Unformatted text preview:

Unit II ReviewChapter 8: Plant Systematics and DarwinianI. Scientific Namesa. Similar plant species form a group called genus (plural: genera)b. Genera are grouped into familiesc. Families into orders, classes, divisions and kingdomsd. Kingdom > Division > Class > Order > Family > Genus > Speciesi. “King David Came Over For Great Spaghetti”II. Species Namea. Each species has a single correct scientific name in Latin called a binomial (2 names) – it is always italicized or underlinedi. First name is genus nameii. Second name is species name1. Human: homo sapiens2. Cat: felis catusIII. Taxonomic Hierarchy a. Species that have many characteristics in common are grouped into a genusb. Related genera that share combinations of traits are grouped into familiesc. Families are grouped into ordersd. Orders into classese. Classes into divisions (or phyla for animals)f. Related divisions/phyla are grouped into kingdomsIV. Plant Divisionsa. Plants are further classified into ten divisionsi. Bryophyta – mosses, liverwortsii. Psylophytaiii. Lycophyta – club mossesiv. Sphenophyta – horsetailsv. Pterophyta – fernsvi. Cycadophyta – cycadsvii. Ginkgophyta – ginko bilobaviii. Coniferophyta – conifersix. Gentophyta – gnetophytesx. Magnoliophyta – flowering plantsV. What is a species ?a. Species – a set of individuals that are closely related by descent from a common ancestor and ordinarily can reproduce with each other, but not with members of any other speciesb. Morphological Species Concept – based on their morphological features (shape, size, body parts)c. Biological Species Concept – a group of interbreeding populations (offspring are fertile)d. Evolutionary Species Concept – a group of individuals with a common evolutionary lineagee. Some species are capable of interbreeding by Morphologically look differentf. Some plants look the same but due to polyploidy (more than the diploid number of chromosomes), they cannot interbreed – ferns; evening primroseVI. Carolus Linnaeusa. Swedish scientistb. Called the “Father of Systematic Botany” and the “Father of Taxonomy”c. Established modern system of nomenclatured. His most important work was his Binominal System of Nomenclature, in which the genus and species names are usedVII. Evolutiona. A genetic change in a population of organisms that occurs over time, often adapting to an environment or way of lifeb. Evolutionary changes must be genetically inherited, not acquiredVIII. Lamarckism a. Holds that traits are acquired (or diminished) during the lifetime of an organism can be passed to its offspringb. Based on two observations thought to be true in his day:i. “Use it or lose it” – individuals lose characteristics they do not require anddevelop those which are usefulii. Inheritance of acquired traits – individuals inherit the acquired traits of their ancestorsc. Ex: giraffes to reach leaves leads to offspring with longer necksd. This theory was disprovedIX. Darwin a. Thought of an organism not as constant, unchanging or “specially created beings”b. Could not believe that organisms today appeared as they have always appearedc. Changed biological thought forever with the concept of Natural SelectionX. Natural Selection a. Variation – members of a population have individual differences that are inheritablei. Natural selection won’t work in a population of clonesii. The key to variation is sexual reproductionb. Over Production – natural populations reproduce geometrically, producing much more offspring than will survivec. Competition – individuals compete for the same limited natural resourcesi. “Struggle for existence”d. Survival to Reproduce – only those individuals that are better suited to the environment survive and reproduce “Survival of the Fittest”i. Fit individuals pass on to a portion of their offspring the advantageous characteristicse. Long periods of time must be available in order to change to a completely different species; changes are slowf. Off spring that inherit the advantageous traits (favorable genes) are selected fori. Their chances of survival are greaterii. May live to reproductive ageiii. My pass on those desirable attributes to future generationsXI. Artificial Selection a. Selective breeding as practiced by humans on domesticated plants and animalsXII. Gradualism a. Traditional view that states evolution occurs as a slow and steady accumulation ofchanges in organisms (Darwinian evolution)… not much evidenceXIII. Punctuated Equilibrium a. Evolution proceeds with periods of inactivity, followed by periods of very rapid evolutioni. Fossil record supports this viewii. Long periods of stasis (no change in species)iii. Followed by rapid changeChapter 9: Evidence for Evolution and Plant AdaptationsI. Three Types of Natural Selection a. Directional Selection – one trait at the extreme of the range is favored over individuals with the average or opposite extreme of the traitb. Stabilizing Selection – the average trait is favored over the extreme traitsc. Disruptive Selection – the extreme traits are favored over individuals with the average traitsII. Evidence in Support of Evolution a. Evidence of evolution can be found in extant organisms (living organisms):b. Comparative Anatomy: i. Homologous Organs – organs similar in form in different organisms due to a common evolutionary origin1. Share same common origin, but may have different functions (same bound structure found in a human arm, bad wing ect)ii. Analogous Organs – organs that have similar look and/or functions in different organisms but do not share a common evolutionary origin1. Wings of insects vs. wings of birds2. Similar function of tendrils (climbing), but different origin (leaf vs.stem)iii. Convergent Evolution – the process by which unrelated organisms in a similar environment evolve similar adaptive structures and physiol1. Example: cacti (North America deserts)iv. Vestigial Organs – organs or parts of organs that are non-functional and degenerate1. An organ loses its function, no selective advantage to have it, but no selective pressure to get rid of it (leg bones in snakes)c. Mimicry and Protective Coloration: i. Mimicry – a harmless species may resemble a dangerous speciesii. Protective Coloration – allows an organism to blend with environment d. Developmental Biology :i. Early embryos


View Full Document

UMD BSCI 124 - Unit II Review

Download Unit II Review
Our administrator received your request to download this document. We will send you the file to your email shortly.
Loading Unlocking...
Login

Join to view Unit II Review and access 3M+ class-specific study document.

or
We will never post anything without your permission.
Don't have an account?
Sign Up

Join to view Unit II Review 2 2 and access 3M+ class-specific study document.

or

By creating an account you agree to our Privacy Policy and Terms Of Use

Already a member?