Characteristics of Life

All living things share the following characteristics…

1. Consist of Cells

• Cells are the basic unit of structure and function

• Consist of DNA

• Very basis of life

• Microscopic

2. Are highly organized

• Higher ordered organisms like you and me consist of…– Cells– Tissue– Organs– Organ systems– Organism

3. Respond to Stimuli

• All living things respond to their environment

• Living things are able to regulate their internal conditions.– Homeostasis

• Regulation of internal body conditions– Sweating– shivering

4. Require Energy

• Energy needed to respond, move, grow, reproduce…

• Energy is obtained in chemical form– Sugars– Fats– Lipids

• Energy can be followed through ecosystems– Sun -- producer -- consumer-- secondary

consumer– Energy lost at every stage

5. All living things have the ability to reproduce

• There are two modes

of reproduction– Sexual

• meiosis

– Asexual• Mitosis

6. Growth and Development

• All organisms go through maturation

• Have some sort of life cycle

• Go through cell division

7. The Ability to Adapt

• Definition of adaptation:– An inherited trait that helps an organism

survive and reproduce in a certain environment

• Natural selection:– AKA - survival of the fittest- only the strong

survive

• Adaptation leads to evolution.

Now that we know what life is how would it be ordered?

Order the following from smallest to largest

• Organ• Tissue• Cell• Community• Organ system

• DNA• Population• Biosphere• Organism• ecosystem

1. Cell

• Location of organelles

• Consist of DNA

• Location of genes

2. Tissues

• Group of the same type of cells working together to carry out a specific function

3. Organ

• Specialized tissues that work together to perform a specific function

Group of organs working together form an

4. Organ system– Which work together to carry out a vital

body function• Digestive system = mouth - esophagus -

stomach - intestine

5. Organism

6. Population- a population is a group of the SAME species

living in a given area at the same time

7. Community- all organisms living in the same area

8. Ecosystem- All living and nonliving features of the

environment. - Dynamic and constantly changing

8. All of those put together create the Biosphere

• All parts of the planet that are inhabited by living things.

• All of Earth’s ecosystems.

Classification

• Organizing similar species into larger groups.

• Domain = largest most broad• Kingdom = Plant, Animal, Fungi, Protist,

Archea• Phylum, Class, Order, Genus, Species• Species = the most specific

classification of life

Three domain System

• Archeabacteria– Unicellular– Simple cells– Extremophiles– Lack nuclei

• Prokaryotic cells

• Eubacteria– Same as above– Not extremophiles

• Eukarya– Multicellular– Have nuclei

• Eukaryotic cells

Chapters 34-36Ecology

• Ecology:– Study of organisms and their interaction

with their environment

• Environment:– All the living and non living components of

where an organism lives

Biotic vs Abiotic

Habitat vs Environment

• Environment– Biotic and abiotic

components of an area

• Habitat– The specific

environment where an organism lives.

Niche

• An organism’s role or job within its habitat

Biome:

• Group of ecosystems that are characterized by 1. Climate

- Temperature- Precipitation

2. Organisms that live there- Climate determines vegetation which

determines animal life

Biomes presented by groups

WHAT IS THE DIFFERENCE BETWEEN POPULATION AND COMMUNITY?

Community: All of the populations living in an area at a given time.

Population: group of one type of species living in a given area at a given time.

Carrying Capacity

• (k) total number of a population that can survive in an area

• Fluctuates with limiting factors: – Any factor that can control (or limit)

population growth.• Competition• Food • Shelter

Competition: Fighting for resources

Interspecific

• Between organisms of different species and different populations

Intraspecific

• Between organisms of the same population or species

Competitive Exclusion Principle

• No two organisms can share the same niche at the same time

• Leads to stratification of resources.

Predation

• Predator: hunts/kills another organism

•Prey: organism being killed

Parasitism

• One organism benefits and the other is harmed• Parasite: the organism that benefits• Host: the organism that is harmed• Example: tapeworms in GI tract;

Strangler Fig

Mutualism

• Both organisms benefit from each other

• Example: termites have cellulose-digesting microorganisms living in their gut

Commensalism

• One organism benefits and the other is not affected

• Example: Pilot fish are small fish that live with sharks and eat the scraps from the shark feeding

• ENERGY FLOWS THROUGH

• MATTER CYCLES!!!

Types of organisms• Producers (autotrophs):

make their own food– Energy from the sun

• Consumers (heterotrophs): eat other organisms for energy– Herbivores: eat plants– Carnivores: eat animals– Omnivores: eats both

plants and animals– Detritovore: eat broken

down organic matter– Decomposers: break down

remains of plants and animals

Energy Flow…

• One way flow of energy through consumption.

• Arrow points in the directions of energy transfer

Energy flow…

• Food web: all of the energy transfers within a system.

• Several interconnected food chains

Energy Pyramid

• Model of the transfer of energy through consumption

• At every trophic level only ~10% of energy is transferred

• Biomass = dry weight of each level

The Hydrological Cycle

• Movement of water through phase changes

• Where is the water?– 97% is NOT FRESH– 3% IS FRESH

WATER• 68.7 % in glaciers• 30.1% in the ground• .3% is surface water

The Carbon Cycle

• Movement of carbon from inorganic to organic form.

• Photosynthesis + cellular respiration

• How are humans impacting?

Nitrogen cycle

• Changes unusable N2 to a form that can be utilized by living things

• Nitrogen fixation- conversion of N2 to NH3

• NH3 changed to NH4 that is used by plants as well as in NO3

Human impact on the environment

• H ABITAT DESTRUCTION

• I NVASIVE SPECIES

• P OLLUTION

• P OPULATION GROWTH

• O VERUSE OF RESOURCES

Pollution • Any unwanted change or addition to soil, water, air, that has a negative impact on organisms

• Bioaccumulation– Toxins gather and

add up in an organism throughout its lifetime

• Biomagnification– Those toxins move

and accumulate at [greater] through food chain

Exponential human population growth

• Overusing resources

• Deforestation• Soil Erosion• Food shortages• droughts

Green house effect

• Naturally occurring process.

• Gases trap heat and sunlight in the lower atmosphere to allow a temperature to support life.

• GHG= CH4, H2O, CO2, O3

Climate change

• Due to increase reliance on fossil fuels as energy we are putting more GHG in atmosphere.

• Results in warmer parts of the atmosphere, melting of ice at poles, which gets into ocean currents and changes global patterns.

Ozone Layer

• Made of O3 and is a layer in the atmosphere that keeps out harmful UV radiation.

Ozone Depletion

• Realized that through use of CFCs we inadvertently began breaking down the ozone layer. When the once stable chemical broke down in the atmosphere.

• Through phasing out of CFC and Ozone depleting compounds the ozone has begun repairing itself.