copyright cmassengale Study of Biology copyright cmassengale

copyright cmassengale What is Biology? Biology is the study of all living things Living things are called organisms Organisms include bacteria, protists, fungi, plants, & animals copyright cmassengale

All Living Things Share Common Characteristics Basic Unit is the CELL They REPRODUCE. All Based On Universal Genetic Code (DNA) They need food for ENERGY RESPOND to their environment copyright cmassengale

Common Characteristics and Unifying themes within systems Grow and Develop Maintain A Stable Internal Environment or HOMEOSTASIS AS A GROUP, Living Things EVOLVE, That Is They Change Over Time copyright cmassengale

Characteristics of Organisms copyright cmassengale

1. All Organisms are made of Cells copyright cmassengale

copyright cmassengale 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 copyright cmassengale

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

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

copyright cmassengale 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 copyright cmassengale

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 copyright cmassengale

2. Organisms Reproduce to Pass on their Genetic Traits copyright cmassengale

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

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

Cells Have a Genetic Code copyright cmassengale

copyright cmassengale 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 copyright cmassengale

3. Cells Require Food & Energy copyright cmassengale

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

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

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

copyright cmassengale Metabolism Cellular Respiration Cells releasing the chemical energy stored in foods 6O2 + C6H12O6 6CO2 + 6H2O copyright cmassengale

4. Organisms Respond to Stimuli (respond to their environment) Organisms Respond to stimuli (Temperature, Water, Food Supplies, etc.) In Order To Survive & Reproduce copyright cmassengale

5. Organisms Grow & Develop copyright cmassengale

copyright cmassengale Growth & Development Organisms grow by producing MORE CELLS & by cell ENLARGEMENT Organisms develop as they mature into an adult organism copyright cmassengale

copyright cmassengale 5. 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. copyright cmassengale

copyright cmassengale 7. 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 copyright cmassengale

Life is Organized on Several Levels copyright cmassengale

copyright cmassengale Levels Atoms Molecules Organelles Cells – life starts here Tissues Organs System Organism copyright cmassengale

copyright cmassengale Levels Population Community Ecosystem Biosphere copyright cmassengale

copyright cmassengale