Living Things and Classification Six Kingdoms What is

Living Things and Classification Six Kingdoms

What is an organism? An organism is a living that carries out all 6 characteristics of living things.

• There are SIX Characteristics of Living Things– 1. Cellular Organization– – Cells are the basic building blocks of all organisms. ALL living things are made up of cells Unicellular –one cell Multicellular – many celled 2. Contain Similar Chemicals – – – Water (approximately 70% of the cell) Carbohydrates- energy source Proteins- for growth and repair Lipids- are fats Nucleic Acids- DNA and RNA – Lipids and Proteins are the building blocks of cells

Characteristics of Life (Continued) • 3. Use Energy– For growth and repair – For cellular processes (respiration, photosynthesis, reproduction) – For digestion • 4. Growth and Development– Growth- becoming larger – Development- becoming more complex over an organisms life span

Characteristics of Life (Continued) • 5. Response to Surroundings – Plants grow (bend) toward the light – Amoeba will move away from light and toward food – Stimulus – something that causes a change in an organism’s environment – Response- reaction or change in behavior by the organism

Characteristics of Life (Continued) • 6. Reproduction – An organism makes more of itself – Asexual- 1 parent, offspring is identical to the parent (bacteria, skin cells) – Sexual- 2 parents, offspring not identical to either parent (humans, dogs, plants)

Classification of Living Things (25 min)

Life Comes From Life • A long time ago, people believed that living things could suddenly appear from nonliving material – Maggots on rotting meat – Creature from the swamp • This is theory of Spontaneous Generation

Controlled Experiments- proved that Spontaneous Generation could not occur • Francesco Redi- (mid 1600’s) • Rotting meat in jars • Disproved spontaneous generation • Louis Pasteur- (mid 1800’s) • Broth in flasks • Finally convinced people that spontaneous generation was wrong

Both Redi and Pasteur: • Used a Controlled Experiment – An controlled experiment is when only one variable is changed. – In Redi’s experiment the manipulated variable is the cloth – In Pasteurs experiment the manipulated variable is With or without a neck on the flask

The Needs of Living Things Autotrophs- Homeostasis Energy maintain stable internal conditions Heterotrophs – Autotrophs- make their own food (plants) – Heterotrophs- can not make their own food (animals) Water is necessary for all cellular processes (digestion, reproduction, circulation) Living Space food, water, shelter

• Living organisms must be able to adapt to their environment and maintain homeostasis to make sure it can carry out all cellular processes. Healthy Diet Poor Diet Proper Rest Stress Healthy Lifestyle Unhealthy Environmental Factors

The Earth 3. 6 Billion Years Ago • Landscape was rugged with jagged, bare rocks…. little soil • Atmosphere consisted of nitrogen, water vapor, carbon dioxide, hydrogen, ammonia and methane. NO FREE OXYGEN • Oceans were shallow and warm

Major Gases in Early and Today’s Atmosphere TODAY’S EARLY Water Vapor Carbon Dioxide Methane Hydrogen Ammonia Nitrogen Oxygen

Origin of Life • Scientists tell us that the first life forms appeared on Earth 3. 6 billion years ago. • Facts we know about Early life forms 1. unicellular 2. lived in the oceans 3. did not need oxygen to live 4. they were heterotrophs that used chemicals for their energy source They resembled the Archaebacteria of today

How did these early life forms originate? • Although Redi and Pasteur proved life could can not spontaneously arise on Today’s Earth, Two American scientists, Harold Urey and Stanly Miller hypothesized on the Ancient Earth the first cells probably did arise from non living materials.

Urey and Miller’s Experiment lightning

Urey and Miller (4 min)

The first cells were bacteria. These pictures are of fossilized bacteria dated to be 3. 4 - 3. 5 billion years old These first cells were heterotrophs. Over time, these cells developed the ability to make their own food and began to excrete oxygen. This was the beginning of our atmosphere of today.

Hydrothermal Vents (6 min)

Classification * Grouping things based on their similarities • Taxonomy- is the science of classification • Aristotle was the first scientist to record a classification system for animals. • It was based on whether animals could fly- swimwalk, crawl, or run

Carolus Linnaeus • In the 1750’s, Linnaeus expanded the classification system • He devised a two word naming system. Binomial Nomenclature • Genus- first word • Species- both words (second word gives a more specific characteristic)

Some Examples • • Felis concolor Felis pardalis Felis domesticus Felis- genus with sharp, retractable claws that hunt other animals • concolor- means same color (puma) • pardalis- means spotted like a panther (ocelot) • domesticus- of the house (house cat)

Levels of Classification • There are SEVEN levels of classification – Kingdom (most broad) – Phylum – Class – Order – Family – Genus – Species (most specific)

Six Kingdoms • Linnaeus proposed the first kingdom structure (2 kingdoms- plants and animals) • Today organisms are classified into SIX Kingdoms – Archaebacteria – Eubacteria – Protists - Fungi - Plants - Animals

How Do We Place Organisms Into Kingdoms? • Type of cells- Prokaryote- no nucleus Pro – nucleus - Eukaryote- has a nucleus U – have – nucleus

• Ability to make food – Autotroph-make their own food – Heterotroph-can not make own food

Number of cells – Unicellular • Single-celled – Multicellular • More than one cell

Archaebacteria vs. Eubacteria Similarities • Both are unicellular • Both are prokaryotes • Both can be autotrophs or heterotrophs Differences • Archaebacteria are found in extreme, harsh environments • Their chemical makeup is different from each other

Eubacteria can be helpful by: • Making vitamins in our bodies • Producing foods like sour dough bread, yogurt and sauerkraut • Recycle chemicals such as nitrogen to the soil as a decomposer

Heterotroph Autotroph and Heterotroph

Charles Darwin • Evolution and Classification In 1859 Darwin published a theory about how species can change over time Darwin collected much of his data in the Galapagos Islands aboard the HMS Beagle

Darwin’s Finches Cactus Finch Nectar eater Warbler Finch Insect eater Ground Finch Seed eater

Darwin’s Galapagos Islands (10 min)

Natural Selection • Darwin explained his Theory of Evolution by using the idea of what he called Natural Selection – as an organism changes over time, if the changes help them to survive the changes will be passed on to their offspring

Darwin and Natural Selection (4 min)

Classification Today • In addition to the work of Darwin and others, today we also study fossils of organisms and we compare the early development of organisms to obtain information on similar evolutionary history.

Most Advanced Classification Method • With the advancement of DNA research, taxonomists today primarily use chemical analysis of the cell to classify organisms. New Family: Mephitidae “noxious gas” Family: Mustelidae

Chemical Classification (4 min)

Heterotroph Autotroph and Heterotroph