The Study of LifeThe Study of Life

All Living Things Share All Living Things Share Common Common

CharacteristicsCharacteristics1.1. Basic Unit is the CellBasic Unit is the Cell

2.2. They ReproduceThey Reproduce

3.3. Grow & DevelopGrow & Develop

4.4. Respond To Their Respond To Their EnvironmentEnvironment

5.5. Maintain A Stable Internal Maintain A Stable Internal EnvironmentEnvironment

6.6. Have Complex ChemistryHave Complex Chemistry

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

The simplest cells are called Prokaryotes

a. These cells DO NOT have a nucleus or membrane-bound organelles

b. Archaea and Bacteria are examples

More complex cells are called Eukaryotes

a. These cells DO have a nucleus and membrane-bound organelles

b. Eukarya (plants, animals, & fungi) are examples

Unicellular Organisms - Living Organism Made Up Of One Cella. Examples: Archaea and Bacteria

Multicellular Organisms - Living Organism Made Up Of Many, Specialized Cellsb. Examples: Eukarya

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

Organisms Grow & Develop

Growth & Development

•Cells grow by producing MORE CELLS & by cell ENLARGEMENT

•Organisms develop as they mature into an adult organism

Organisms Respond to Environment

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

Homeostasis

•Keeping The Internal Environment Of The Cell or Organism Within The Ranges Required For Life

•Stable internal conditions of pH, temperature, water balance, etc.

Living things have complex chemistry

•Consist of large complex chemicals

•Undergo complex chemical reactions to carry out all functions for life

Unifying Themes of Biology

•Cell theory•Gene theory•Homeostasis•Evolution

Cell Theory

• All living things are made of cells

• Living cells come from other living cells

• Living things can be unicellular (bacteria) or multicellular (plants, animals)

Gene Theory

• Characteristics of living things are controlled by genes

• Genes are passed on from parents to offspring

Homeostasis

• Maintaining a stable environment

Evolution

• Change in the characteristics of living things over time

• Evolution occurs through natural selection

• Organisms with more suitable adaptations for their environment are able to survive and reproduce

Life is Organized on Life is Organized on Several LevelsSeveral Levels

Organizational Levels of LifeOrganizational Levels of Life

A. BiosphereA. Biosphere1. Consists of all the parts 1. Consists of all the parts

of of the planet that are the planet that are inhabited by living inhabited by living

thingsthings

2. Includes most regions of 2. Includes most regions of land; most bodies of land; most bodies of

water and water and the atmosphere the atmosphere to an altitude to an altitude of several of several kilometerskilometers..

B. Biome – a group of similar B. Biome – a group of similar ecosystems with the same ecosystems with the same

general general type of physical type of physical environmentenvironment

Ex: tundra, desert, Ex: tundra, desert, tropical tropical rainforestrainforest

C. EcosystemsC. Ecosystems1. An ecosystem is the 1. An ecosystem is the

community community of living things in of living things in an area, along an area, along with the with the nonliving features of the nonliving features of the environment that support the environment that support the living living community.community.

a) Example: A forest a) Example: A forest (includes various types of (includes various types of

trees trees and plants, animals, and plants, animals, microscopic microscopic forms of life, forms of life, soil, water, air, soil, water, air, sunlight, sunlight, etc.)etc.)

D. Community – all the D. Community – all the populations in an populations in an areaarea

What makes up the What makes up the community in you community in you classroom?classroom?

E. Population – organisms of the E. Population – organisms of the same same species living in the same species living in the same areaarea

F. Organisms - are individual F. Organisms - are individual living living thingsthings

a) Examples: squirrels, insectsa) Examples: squirrels, insects

G. Organ system – group of organs G. Organ system – group of organs that work togetherthat work together

H. Organs – composed of one or H. Organs – composed of one or more more types of tissuestypes of tissues

I. Tissues- group of cells of the I. Tissues- group of cells of the same same kindkind

J. Cells - life’s basic units of J. Cells - life’s basic units of structure and functionstructure and function

The Diversity of LifeThe Diversity of LifeA. SpeciesA. Species

1. A species is a distinct form 1. A species is a distinct form of lifeof life

a) ~ 5,000 species of a) ~ 5,000 species of bacteria; ~8,600 bacteria; ~8,600

species of species of birds; ~30,000 birds; ~30,000 species of species of fishes; fishes; ~100,000 species of ~100,000 species of fungi; fungi; ~280,000 species of ~280,000 species of plants; plants; and ~1,000,000 and ~1,000,000 species of insectsspecies of insects

B. The 3 domains of LifeB. The 3 domains of Life1. A domain is the broadest 1. A domain is the broadest category for classifying life category for classifying life

formsforms

2. There are 3 domains: 2. There are 3 domains: Archaea, Bacteria, and Archaea, Bacteria, and

EukaryaEukarya

C. Typical 6 kingdomsC. Typical 6 kingdoms