Characteristics of Living Systems

Living Systems Biology - The science of life and all living organisms, including their structure, function, growth, origin, evolution, and distribution. It includes botany and zoology and all their subdivisions. BOTANY – study plants ZOOLOGY – study animals PALEONTOLOGY – study past (ancient) life forms ECOLOGY – study of life and surroundings (environments)

Living Systems 1. All organisms are composed of one or more cells 2. All organisms are able to grow, reproduce and adapt 3. All organisms use energy 4. All organisms maintain homeostasis 5. All organisms respond to the environment 6. All organisms receive instructions from DNA

1. Cell Theory All living things are made up of cells. Cells are the smallest working units of all living things. All cells come from preexisting cells through cell division.

Definition of Cell A cell is the smallest unit that is capable of performing life functions.

Examples of Cells Amoeba Proteus Plant Stem Bacteria Red Blood Cell Nerve Cell

Prokaryotic Eukaryotic (animal cells) Two Types of Cells Prokaryotic Eukaryotic (animal cells)

2. Adaptation Any structure, behavior, process that promotes survival of a species. Cactus – have thorns Camels – have humps of FAT on their backs Camels foot – webbed to trek terrain

3. Organisms use energy All Life needs energy- photosynthesizers use solar energy, (autotrophs) chemosynthesizers use chemical energy, (autotrophs) Most other organisms use the energy stored as the bodies of the these two. (heterotrophs)

4. Homeostasis Steady state of being regardless of external surroundings. Maintaining a stable internal environment Shiver when cold. Sweat when hot.

5. Environment- surroundings Biotic factors – all things alive or that once lived. Abiotic factors – all things that never lived but affect life.

6. Instructions from DNA Every living thing has DNA. That means that you have something in common with a zebra, a tree, a mushroom and a beetle!!!!

Classification Taxonomy naming system for the organization of life. Grouping or categorizing based on similarities Modern classification began with the work of Carolus Linnaeus, who grouped species according to shared physical characteristics. In the life sciences, binomial nomenclature is the formal method of naming species. As the word "binomial" suggests, the scientific name of a species is formed by the combination of two terms: the genus name and the species descriptor.

Classification of living systems Kingdoms Phylum Class Order Family Genus Species

} Classification 6 KINGDOMS Animalia Plantae Fungi Protista Prokaryotes Eukaryotes Viruses are not classified as living. Viruses do however demonstrate reproductive capabilities like living things. They are smaller than bacterial cells! } Used to be 1 kingdom- Monera (Bacteria only)

The 6 kingdoms Prokaryotes (Used to be 1 kingdom, Monera) Eukaryotes Archaebacteria Eubacteria Eukaryotes Fungi Protista Animal Plantae

Overview of the 6 kingdoms Archaebacteria Unicellular Live in extreme environments Prokaryotic Eubacteria “Common bacteria”

Overview of the 6 kingdoms Protista Eukaryotic Unicellular or colonial Lots of different life styles Fungi Cell walls made of chitin Multicellular External heterotrophs

Overview of the 6 kingdoms Plantae Eukaryotic & Multicellular Cell walls made of cellulose Autotrophic Animalia No cell walls Internal heterotrophs

Let’s look at an example!

What is my name? Puma ?

What is my name? Devil Cat ?

What is my name? Ghost Cat ?

My real name is Puma concolor What is my name? My real name is Puma concolor

Binomial Nomenclature There are at least 50 common names for Puma concolor. Common names vary according to region, country or language. Soooo……why use a scientific name?

Binomial Nomenclature     Two name system for writing scientific names. The genus name is written first (always Capitalized).     The species name is written second (never capitalized).     Both words are italicized if typed or underlined if hand written. The name is also in Latin (a dead language).

Binomial Nomenclature More examples- Genus and species Common name Range Panthera leo Lion Africa (Asia) Panthera onca Jaguar N. & S. America Panthera pardus Leopard Africa, Asia, Europe Panthera tigris Tiger Asia

How many organisms are out there? Scientists currently estimate that There are 10 million species worldwide Over 5 million live in the tropics Most unnamed species are small or microscopic

Why is taxonomy useful? Helps prevent confusion among scientists Helps to show how organisms are related Can be used to reconstruct phylogenies – evolutionary histories – of an organism or group

Organization of LIFE CELL – BASIC UNIT OF LIFE TISSUE- MANY CELLS ORGANS- MANY TISSUES ORGAN SYSTEMS-GROUPED ORGANS ORGANISMS – CONTAINS ORGAN GROUPS SPECIES- GROUPS OF THE SAME ORGANISM