Study of Biology

1. Study of Biology

2. What is Biology? • Biologyis the study of all living things • Living things are called organisms • Organisms include bacteria, protists, fungi, plants, & animals

3. All Living Things Share Common Characteristics • Basic Unit is the Cell • They Reproduce • All Based On Universal Genetic Code (DNA) • Grow & Develop

4. Common Characteristics • Obtain & Use Materials & Energy • Respond To Their Environment • Maintain A Stable Internal Environment • AS A GROUP, Living Things Evolve, That Is They Change Over Time

5. Characteristics of Organisms

6. All Organisms are made of Cells

7. Facts About Cells • Cells are the smallest living unit of an organism • All cells contain living material called cytoplasm • All cells are surrounded by a cell membrane that controls what enters & leaves the cell

8. More Cell Facts • Cells are complex & highly organized • Cells have parts called organelles that do different jobs e.g. Chloroplasts in plants make sugars

9. More Cell Facts • The simplest cells are called Prokaryotes • These cells DO NOT have a nucleus or membrane-bound organelles • Bacteria are examples

10. More Cell Facts • More complex cells are called Eukaryotes • These cells DO have a nucleus and membrane-bound organelles • Plants, animals, protists, & fungi are examples

11. Organisms are Grouped by their Number of Cells • Unicellular Organisms • Living Organism Made Up Of One Cell • Multicellular Organisms • Living Organism Made Up Of Many, Specialized Cells

12. Organisms Reproduce to Pass on their Genetic Traits

13. Sexual Reproduction Involves 2 parents Egg fertilized by sperm to make a ZYGOTE Offspring DIFFERENT from parents Two Types of Reproduction

14. Asexual Reproduction Involves a single organism or cell Cell divides Offspring IDENTICAL to parent Two Types of Reproduction

15. Cells Have a Genetic Code

16. Genetic Code • DNA (deoxyribose nucleic acid) carries the genetic code for all organisms • All organisms contain DNA • DNA codes for the proteins that make up cells & do all the work

17. Organisms Grow & Develop

18. Growth & Development • Organisms grow by producing MORE CELLS & by cell ENLARGEMENT • Organisms develop as they mature into an adult organism

19. Cells Require Food & Energy

20. Autotrophs can make their own food Photoautotrophs use sunlight to make food (photosynthesis) Chemoautotrophs use chemicals such as iron & sulfur as their energy Food Requirements

21. Food Requirements • Heterotrophs can NOT make their own food • They must consume other organisms • Herbivores eat plants • Carnivores eat meat • Omnivores eat plants & animals

22. Metabolism • Sum of all the chemical reactions in an organism • All require energy • Sunlight is the ultimate energy for life on Earth

23. Metabolism • Cellular Respiration • Cells releasing the chemical energy stored in foods 6O2 + C6H12O6 6CO2 + 6H2O

24. Organisms Respond to Stimuli • Organisms Respond to stimuli (Temperature, Water, Food Supplies, etc.) In Order To Survive & Reproduce

25. Homeostasis • Keeping The Internal Environment (Homeostasis) Of The Cell or Organism Within The Ranges Required For Life • Stable internal conditions of pH, temperature, water balance, etc.

26. Living Things Evolve • Groups Of Organisms (Not Individuals) Change Over Time In Order To Survive Within Changing Environments. • Fossil records show changes in groups of organisms

27. Life is Organized on Several Levels

28. Levels • Atoms • Molecules • Organelles • Cells – life starts here • Tissues • Organs • System • Organism

29. Levels • Population • Community • Ecosystem • Biosphere

31. The End!!! • Thank you for your attention. • Write a 2-paragraph (10 sentences) summary of your understanding of the topic.