Study of Biology copyright cmassengale1. What is Biology? Biology is the study of all living things...

Study of Biology

copyright cmassengale 1

What is Biology?

• Biology is the study of all living things

• Living things are called organisms

• Organisms include bacteria, protists, fungi, plants, & animals


All Living Things Share Common Characteristics

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

Genetic Code (DNA)4. Grow & Develop


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


Characteristics of Organisms


http://ethnopharmacology.com/index.html

All Organisms are made of Cells


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


More Cell Facts• Cells are complex &

highly organized• Cells have parts

called organelles that do different jobs

e.g. Chloroplasts in plants make sugars


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 9

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


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


Organisms Reproduce to Pass on their Genetic

Traits


Two Types of Reproduction

• Sexual Reproduction

• Involves 2 parents

• Egg fertilized by sperm to make a ZYGOTE

• Offspring DIFFERENT from parents


Two Types of Reproduction

• Asexual Reproduction

• Involves a single organism or cell

• Cell divides• Offspring

IDENTICAL to parent


Cells Have a Genetic Code


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


Organisms Grow & Develop


Growth & Development

• Organisms grow by producing MORE CELLS & by cell ENLARGEMENT

• Organisms develop as they mature into an adult organism


Cells Require Food & Energy


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


Food Requirements

• Heterotrophs can NOT make their own food

• They must consume other organisms

• Herbivores eat plants• Carnivores eat meat• Omnivores eat plants & animals


Metabolism

• Sum of all the chemical reactions in an organism

• All require energy• Sunlight is the ultimate

energy for life on Earth


Metabolism

• Cellular Respiration –Cells releasing the chemical energy stored in foods

6O2 + C6H12O6 6CO2 + 6H2O


Organisms Respond to Stimuli

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


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.


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 26

Life is Organized on Several Levels


Levels• Atoms• Molecules• Organelles• Cells – life starts

here• Tissues• Organs• System• Organism


Levels

• Population• Community• Ecosystem• Biosphere


Study of Biology copyright cmassengale1. What is Biology? Biology is the study of all living things...

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