1 / 26

Stuff you need to know…

Stuff you need to know…. Sex-Linked Genes : genes that are on the X or Y chromosome *because any gene on the Y chromosome will always affect males & only males, these problems only discuss genes on the X chromosome

meryl
Download Presentation

Stuff you need to know…

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Stuff you need to know…

  2. Sex-Linked Genes: genes that are on the X or Y chromosome *because any gene on the Y chromosome will always affect males & only males, these problems only discuss genes on the X chromosome *females have 2 X chromosomes & males have 1 therefore, males are more likely to exhibit recessive phenotypes fro sex-linked genes

  3. TERMS TO KNOW!! ·EVOLUTION: cumulative change in the heritable characteristics of a population (“CHANGE OVER TIME”) ·FITNESS: refers to traits and behaviors of organisms that enable them to survive and reproduce

  4. ·ADAPTATION: any inherited characteristic that enhances an organism’s ability to survive and reproduce in that particular environment ~based on variations randomly inherited (mutation & meiosis)

  5. Charles Darwin’s Explanation on Evolution (six major ideas of Darwin) Not all organisms can survive Overproduction occurs in nature Variation occurs in all populations Variations are inherited Organisms with favorable variations survive and reproduce Populations as a whole become FIT = evolved!

  6. Insecticide applied

  7. Genetic Drift Changes in the gene pool (# or % of “A” allele vs “a” allele) of a small population due to chance Examples: -Bottleneck Effect: results from drastic decrease in population size -Founder Effect: few individuals in a population colonize a new habitat

  8. Bottleneck Effect

  9. Speciation The origin of new species (the appearance of new species is the source of biological diversity) • Reproductive Isolation: barriers that prevent members of two species from producing viable, fertile hybrids

  10. Geographic Isolation: Gene flow between gene pools is interrupted when a population is divided into two geographically isolated subpopulations • Ex: the water level in a lake decreases • Ex: a river splits a population into two

  11. Ecology

  12. 1) Life is ORGANIZED on many structural levels: Atoms Biological Molecules Subcellular organelles Cells Tissues Organs Organ Systems Complex Organism

  13. Levels beyond the individual organism: Population Community Ecosystem Biomes Biosphere

  14. Biodiversity • Definition: the number and variety of organisms found within a specified geographic region • affected by alterations of habitats.

  15. fluctuations in population size in an ecosystem are determined by the relative rates of birth, immigration, emigration, and death. • Change in pop size = [B + I] – [D + E]

  16. Review • Autotrophs—capture energy from sunlight or chemicals and use that energy to produce food • AKA producers • Photosynthesis • Plants • Chemosynthesis • Bacteria

  17. Heterotrophs (Consumers) • Herbivores • Carnivores • Omnivores • Detritivores • Feed on plant and animal remains (have a mouth; ingest food) • Mites, earthworms, snails • Decomposers • Break down organic matter • Bacteria and fungi

  18. Flow of Energy Energy flows through an ecosystem (a section of the biosphere) from the sun, to producers, to consumers IN ONE DIRECTION!!!

  19. Food Chains • Food Chain—transfer of energy by eating and being eaten

  20. Food Webs • Food Web—describes complex relationships of organisms in an ecosystem • A food web links together all the food chains in an ecosystem

  21. Energy Pyramid Tertiary Consumers Primary Consumers • each step of an organism eating another organism is called a trophic level (trophe means food in Greek) • Shows the relative amounts of energy contained within each trophic level in a food chain or food web • Only part of the energy that is stored in one trophic level is passed on…(10%) Producers

  22. Approximately 10% of the energy at one trophic level can be used by animals at the next trophic level • ex: 90% of produced/consumed energy is used in that organisms cellular respiration • Only 10% incorporated into tissues

  23. More energy efficient to eat producers • Although energy moves in a one-way direction through an ecosystem, nutrients are recycled

  24. Succession • series of changes in an ecological community that occur over time after a disturbance

  25. Fossils-Any preserved evidence of life from a past geological age (ex: impressions & remains of organisms embedded in stratified rocks; mineralized remains of an animal or plant Fossils include shells, imprints, burrows, and organically-produced chemicals. The oldest fossils are of bacteria (prokarytotes) & they are 3.8 billion years old.

  26. Bacteria vs.Virus

More Related