Characteristicsoflife

1

Study of Biology

copyright cmassengale

2

What is Biology?

Biology is the study of all living things Living things are called organismsOrganisms include bacteria, protists, fungi, plants, & animals


3

All Living Things Share Common

Characteristics1. Basic Unit is the Cell2. They Reproduce3. All Based On Universal

Genetic Code (DNA)4. Grow & Develop


4

Common Characteristics

5. Obtain & Use Materials & Energy

6. Respond To Their Environment

7. Maintain A Stable Internal Environment

8. AS A GROUP, Living Things Evolve, That Is They Change Over Time


5

Characteristics of Organisms


http://ethnopharmacology.com/index.html

6

All Organisms are made of Cells


7

Facts About CellsCells are the smallest living unit of an organismAll cells contain living material called cytoplasmAll cells are surrounded by a cell membrane that controls what enters & leaves the cell


8

More Cell FactsCells are complex & highly organizedCells have parts called organelles that do different jobs

e.g. Chloroplasts in plants make sugars


9

More Cell FactsThe simplest cells are called ProkaryotesThese cells DO NOT have a nucleus or membrane-bound organellesBacteria are examples copyright cmassengale

10

More Cell FactsMore complex cells are called EukaryotesThese cells DO have a nucleus and membrane-bound organellesPlants, animals, protists, & fungi are examples copyright cmassengale

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

Two Types of Reproduction

Sexual ReproductionInvolves 2 parentsEgg fertilized by sperm to make a ZYGOTEOffspring DIFFERENT from parents


14

Two Types of Reproduction

Asexual ReproductionInvolves a single organism or cellCell dividesOffspring IDENTICAL to parent


15

Cells Have a Genetic Code


16

Genetic Code

DNA (deoxyribose nucleic acid) carries the genetic code for all organismsAll organisms contain DNADNA 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 ENLARGEMENTOrganisms develop as they mature into an adult organismcopyright cmassengale

19

Cells Require Food & Energy


20

Food RequirementsAutotrophs can make their own foodPhotoautotrophs use sunlight to make food (photosynthesis)Chemoautotrophs use chemicals such as iron & sulfur as their energy


21

Food Requirements

Heterotrophs can NOT make their own foodThey must consume other organismsHerbivores eat plantsCarnivores eat meatOmnivores eat plants & animals


22

Metabolism

Sum of all the chemical reactions in an organismAll require energySunlight 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 LifeStable 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 organismscopyright cmassengale

27

Life is Organized on Several Levels


28

LevelsAtomsMoleculesOrganellesCells – life starts hereTissuesOrgansSystemOrganism


29

Levels

PopulationCommunityEcosystemBiosphere


30copyright cmassengale

31copyright cmassengale

Technology

Characteristicsoflife