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Lesson 2

Lesson 2 . Reproduction and Adaptations. Reproduction and Adaptation. Subtitle. The Importance of Reproduction. Reproduction is not essential to an individual but to the species If individual organisms did not reproduce the population would dwindle.

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Lesson 2

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Presentation Transcript

  1. Lesson 2 Reproduction and Adaptations

  2. Reproduction and Adaptation Subtitle

  3. The Importance of Reproduction • Reproduction is not essential to an individual but to the species • If individual organisms did not reproduce the population would dwindle. • Reproduction is essential for populations to exist.

  4. Asexual and Sexual Reproduction • Asexual – takes only one parent • Binary Fission- single cell divides into two cells • Bacteria and protists • Budding – mass of cells grow on parent and then drop off forming a new organisms • Hydras or yeast • Parthenogenesis – eggs from a female develop into offspring without being fertilized • Insects, fish amphibians and reptiles • Vegetative propagation • Some part of the plant breaks off and begins growing into a new organism • Prickly pear

  5. Sexual Reproduction • -Requires two organisms: eggs from female and sperm from the male • Most plants and fungi • Most fish, amphibians and reptiles • Birds and mammals

  6. How traits are passed on • 1st a copy of the DNA must be made • DNA is the blueprint used to build a new organisms • Genes give instructions for specific traits • In Asexual reproduction offspring is identical to the parent • In sexual reproduction offspring have 2 copies of each gene

  7. Advantages and Disadvantages • Asexual • Advantages • Requires less energy • Can produce offspring fast • Can colonize new habitats quickly • Can take advantages of temporary resources • Disadvantages • Offspring identical to parents • Many die when environmental conditions change

  8. Advantages and disadvantages • Sexual • Advantages • Offspring genetically different • Variation helps some offspring survive if environment changes • Disadvantages • Must have males • Eggs and sperm must meet • Forming reproduction organs uses energy • Courtship uses energy and exposes organisms to injury and predation.

  9. Homogeneity • Organisms with similar genes and traits will be less likely to survive a disease outbreak or a change to its habitat. • Could be cause for extinction

  10. Cause of variation • Environmental Factors • Food more or less abundant • Sunlight and water more or less abundant • Genetic factors • Mutation – a mistake in copying the DNA • Sometimes causes new cell to die • No affect • Traits different from parent • Can occur in asexual or sexual reproduction • Recombination • Sexual

  11. Too many offspring?? • Populations produce more offspring than the environment can support • Environmental factors, food and predators, keep populations in check • Individuals with traits that help them compete for resources, avoid predators and survive are more likely to live long enough to reproduce. • Differenential reproduction occurs in most populations • Some individuals reproduce at a higher rate because they are able to attract more mates • Camouflage • Variations that are beneficial

  12. Natural Selection • Process by which organisms become adapted to their environment over a long period of time • Variation + Differential Reproduction + Heredity = Natural Selection

  13. Examples of Asexual reproduction

  14. Resource Management Subtitle

  15. Bobwhite and managment • Ability to breed • Harvest – bag limits • Natural causes • Recovery the following season

  16. Mead’s Milkweed • Loss of genetic diversity • Delayed grazing and haying • Avoid pesticides • Reduce herbicide use • Use prescribed fire

  17. Missouri’s Greater Prairie Chicken • Translocation

  18. Winter Section Header Layout Subtitle

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