The Organization of Life

1. The Organization of Life Ms. Hubbuch Chapter 4 The Howard School

2. An ecosystem is all of the organisms living in an area together with their physical environment. • It is the abiotic factors and the biotic. • Ecosystems are separate but do not have clear boundaries. • It is important to remember EVERYTHING IS CONNECTED! What is an ecosystem?

3. All ecosystems need the basics: energy, mineral nutrients, carbon dioxide, water, oxygen and living organisms. • These can all be categorized into either biotic or abiotic components. • The smallest unit of an ecosystem in an individual organism. • Organisms are grouped into species based on the ability to reproduce fertile offspring. The components of an ecosystem

4. All the members of a species living in the same place at the same time is called a population. • It is important to remember not all species live together. The squirrels in my backyard do not interact with the squirrels in Atlanta. • An important characteristic of a population is that its members usually breed with one another rather than with members of populations. The components of an ecosystem

5. Every population is part of a community, a group of various species that live in the same place and interact with each other. • It only includes the biotic components. • If we want to include the abiotic components, we would be referring to an ecosystem. • Ecosystems are part of a larger grouping, the biosphere. The components of an ecosystem

7. All organisms live in a particular place called a habitat. • Every habitat has specific biotic and abiotic factors that the organisms living there need to survive. • Organisms tend to be very well suited for their habitats. Habitat

8. In 1859, Charles Darwin observed that organisms in a population differ slightly from each other in form, function and behavior. • Some of the differences were hereditary or passed from parent to offspring. • Darwin proposed the environment exerts a strong influence over which individuals survive to produce offspring with some being more likely than others. • Darwin defined an adaptation as an inherited trait that increases an organism’s chance of survival and reproduction in a certain environment. Natural Selection

9. Natural selection is the term used to describe the survival and reproduction of organisms with particular traits. • Natural selection occurring over several generations causes the characteristics of populations to change. • A change in the genetic characteristics of a population from one generation to another is called evolution. Natural Selection

10. Evolution by Natural Selection

11. Sometimes organisms evolve adaptations to other organisms and their physical environment. • This occurs after a long term interaction and is called coevolution. • The honeycreeper and lobelia plant coevolved. The bird benefits from the nectar while the plant is pollinated. Coevolution

12. Artificial selection is the selective breeding of organisms by humans for specific characteristics. • The many breeds of dogs available are a great example. • Humans have also bred crops to produce the best product possible. Artificial Selection

13. Artificial Selection

14. Sometimes humans cause populations of organisms to evolve unwanted adaptations. • Resistance is the ability of one or more organisms to tolerate a particular chemical designed to kill it. • An organisms may be resistant to a chemical when it contains a gene that allows it to break down the chemical into harmless substances. Resistance

15. Kingdom • Phylum • Class • Order • Family • Genus • Species Diversity of Life

16. 6 Kingdoms • Archaebacteria • Eubacteria • Fungi • Protist • Plants • Animals Diversity of Life

17. Single celled • Reproduce by dividing in half • Often found in harsh environments Archaebacteria

18. Single celled • Reproduce by dividing in half • Incredibly common Eubacteria

19. Absorbs food through body surface • Have cell wall • Typically live on land Fungi

20. Mostly single celled • Primarily aquatic Protist

21. Many cells • Make their own food by photosynthesis • Have cell walls • Divided into three categories: lower plants, gymnosperms and angiosperms Plants

22. Many cells • Ingest food • No cell wall • Categorized as invertebrate and vertebrates Animals

23. Understand the organization of life from species to ecosystems • Be able to explain natural selection and its role in evolution • Understand the mechanism behind pest resistance • List the taxonomic ranks • Name and describe the 6 kingdoms of life and give examples for each At the end of this chapter you should…