Classification PowerPoint PDF

Classification of Living Organisms © Amy Brown Science © Amy Brown Science Scientists have described and named a total of: 1.5 million species. It is estimated that millions of additional species have yet to be identified. Life on earth is constantly evolving and changing slowly over time. Scientist...

Classification of Living Organisms © Amy Brown Science © Amy Brown Science Scientists have described and named a total of: 1.5 million species. It is estimated that millions of additional species have yet to be identified. Life on earth is constantly evolving and changing slowly over time. Scientists attempt to order the natural world by grouping and classifying all living organisms. As technologies improve, so have our systems of classification. A Summary of Darwin’s Theory of Evolution 1. Organisms produce more ________ offspring than can survive. Of the offspring that do survive, many will never reproduce _________. 2. Because more organisms are produced than can survive, there is … … intense competition for limited resources, such as food, water, and shelter. Charles Darwin (1809 – 1882) 3. Individuals that are __________ best suited to their environment survive, reproduce, and pass their traits on to their offspring. Other organisms that are less suited for their environment often die or will not be reproductively competitive. selection ” This is the process of “natural ______________ that causes the many species of organisms on Earth to change over time. The species that are alive on Earth today are descended with modification from ancestral species that lived in the past. For 3.5 billion years, life on Earth has been constantly changing. Natural selection has led to a staggering diversity in organisms. To study this diversity, scientists must give each organism a name and sort them into groups. To study the diversity of life, classification biologists use a ___________ name organisms and system to _____ group them in a logical manner. _____ The branch of biology that classifies organisms and assigns each organism a universally accepted name. Early Attempts at Classification Organisms were first classified 2000 years ago by the more than _____ Aristotle Greek philosopher, ________. Aristotle first sorted organisms into two groups: Plants and animals. He divided animals into three groups: Land dwellers: Water dwellers: Air dwellers: Can you see the problems with this system? He divided plants into three groups: Herbs Shrubs Trees By the 15th and 16th centuries, it became obvious that there were many problems with this system of classification. Many organisms were placed in groups to which they had no real relationship with the other members of the group. The use of common names was very confusing. For example: catfish, jellyfish, shellfish. Many new organisms were being discovered and needed to be classified. In response to the need for a better system of classification, the Swedish naturalist, Carolus Linnaeus _______________, developed the system of classification that we still use today. Carolus Linnaeus (1707-1778) Linnaeus set up a classification system based on structural similarity He thought that the organisms that _________________. the most closely related looked alike were _____________________. Linnaeus developed a system that placed an organism in a group and assigned it a ______________. particular ______ scientific name He developed a naming system called ____________________ binomial nomenclature that is still in use today. The system of assigning a scientific name that consists of two parts. He first divided all organisms into large groups that he called _________. kingdoms He based his classification on two kingdoms: plant and animal. Kingdom Plant Division Division Animal Phylum Phylum A kingdom would be further subdivided into smaller groups. Each subdivision of a phylum kingdom is called a _______ in the animal kingdom, or a division in the plant _______ kingdom. Each subset was further subdivided until he had 7 levels of classification. developed _______ List the seven levels of classification: Kingdom Phylum Class Order Family Genus Species Organisms are placed in the same species if … … they can mate and produce fertile offspring. A species contains … … only one type of organism. In the system developed by Linnaeus, the ________ kingdom was the biggest, broadest group. More recently scientists have added an additional level above domain ”. the kingdom called a “_______ Rules of Binomial Nomenclature (Linnaeus) The scientific name always consists of two words: the genus and the species. All scientific names are in _____. Latin It is understood by all scientists. Rules of Binomial Nomenclature (Linnaeus) The ______ genus name is always capitalized. species name is never capitalized. The _______ Macaca fuscata The two names are always written in italics or underlined. No two organisms can have the same name. Sula nebouxii Below is a chart showing the classification of four different animals. Use the chart to answer the questions below. Animal #1 Animal #2 Animal #3 Animal #4 Animalia Animalia Animalia Animalia Arthropoda Arthropoda Arthropoda Arthropoda Hexapoda Hexapoda Hexapoda Hexapoda Lepidoptera Lepidoptera Lepidoptera Lepidoptera Nymphalidae Nymphalidae Papilionidae Nymphalidae Danaus Vanessa Papilio Danaus plexippus atalanta rutulus gilippus What is the scientific name of Animal #1? Which of these animals belong to the same phylum? Which of these animals belong to the same order? Answers on Slide 24 Below is a chart showing the classification of four different animals. Use the chart to answer the questions below. Animal #1 Animal #2 Animal #3 Animal #4 Animalia Animalia Animalia Animalia Arthropoda Arthropoda Arthropoda Arthropoda Hexapoda Hexapoda Hexapoda Hexapoda Lepidoptera Lepidoptera Lepidoptera Lepidoptera Nymphalidae Nymphalidae Papilionidae Nymphalidae Danaus Vanessa Papilio Danaus plexippus atalanta rutulus gilippus Which of these animals is the most distantly related to the others? Which of these animals belong to the same family? Answers on Slide 24 Below is a chart showing the classification of four different animals. Use the chart to answer the questions below. Animal #1 Animal #2 Animal #3 Animal #4 Animalia Animalia Animalia Animalia Arthropoda Arthropoda Arthropoda Arthropoda Hexapoda Hexapoda Hexapoda Hexapoda Lepidoptera Lepidoptera Lepidoptera Lepidoptera Nymphalidae Nymphalidae Papilionidae Nymphalidae Danaus Vanessa Papilio Danaus plexippus atalanta rutulus gilippus Which two of these animals are the most closely related? How do you know? (Answers on Slide 24) Answers to Questions On Slides 21, 22, and 23 What is the scientific name of Animal #1? Danaus plexippus Which of these animals belong to the same phylum? 1, 2, 3, and 4 Which of these animals belong to the same order? 1, 2, 3, and 4 Which of these animals is the most distantly related to the others? Animal #3 Which of these animals belong to the same family? 1, 2, and 4 Which two of these animals are the most closely related? How do you know? Animals 1 and 4 are the most closely related. They belong to the same genus. Modern Taxonomy: Phylogeny Modern taxonomists consider the phylogeny of an organism when attempting to classify it. Phylogeny: The evolutionary history of an organism. Phylogeny To show the evolutionary relationship between different groups of organisms, scientists construct ________________. phylogenetic trees A phylogenetic tree is a family tree that shows … … the evolutionary relationships thought to exist among different groups of organisms. The phylogenetic tree to the right shows a few of the phyla of the Animal Kingdom. What is the common ancestor of all organisms shown on this tree? Are the Cnidarians more closely related to the sponges or to the Ctenophores (comb jellies)? What is the closest relative to the Rotifers? What does a branch point represent? Answers on Slide 28 Answers to Questions On Slide 27 6. What is the common ancestor of all organisms shown on this tree? Answer: Protists 7. Are the Cnidarians more closely related to the sponges or to the comb jellies (Ctenophores)? Answer: The Ctenophores 8. What is the closest relative to the Rotifers? Answer: Roundworms 9. What does a branch point represent? Answer: A branch point shows the last common ancestor of two or more organisms.. structure of the organism was Traditionally, the morphology (_________) the basis for its classification. Modern taxonomy now takes into account other types of evidence when attempting to classify an organism. gy o l o h p r o M ical g o l ryo ies b m E ri t a l i m Si Cellular Organization Biochemical Similarities Evolutio nary Relation ships Genetic Similar ities Morphology (Structural Similarities) Morphology is classification based on … … the structures possessed by the organism. This was the basis for Linnaeus’ system of classification. The average person would use color and size, but these are the least important in classification. Homologous structures are structures in different species that are similar because of common ancestry. Example: The bones found in the wing of a bird, the wing of a bat, the forearm of a human, and the flipper of a whale are homologous to one another. These are structures in different species that are similar in function but not in structure. Analogous structures are not derived from a common ancestor. Example: The wing of a bird and the wing of a butterfly have the same function, but there is nothing in common in their structure. Vestigial Structures Vestigial Structure: A structure that is reduced in size and seems to be "left over" from a previous ancestor. Remnant of hip bone in whales Examples: Human Appendix and hip bone in whales. appendix The greater the number of homologous structures two organisms share, the more … … closely related they are thought to be. Archaeopteryx The fossil record gives us many clues as to the ___________ morphology of ancient species, but it is an __________ incomplete record. Other lines of evidence must be considered when classifying an organism. Following are 5 additional areas of consideration. Cellular Organization Similarity in ____________ cell structures provides evidence that organisms may be related. Examples: What kinds of plastids are present? Does the cell possess a nucleus? Is there a cell wall present? What is the cell wall composed of? Evolutionary Relationships Scientists now group organisms into categories that represent lines of evolutionary _______, descent or _________. phylogeny Fossils show that organisms ____ alive today are similar to organisms that are now ______. extinct Example: 25 breeds of dogs all came from a wolf-like ancestor. Biochemical Similarities Similarities of __________________ chemical compounds found within cells can be used as evidence to show relationships between organisms. A comparison between the proteins of two organisms serves as a “______________.” molecular clock Simple _________ mutations occur all the time, causing slight differences in the _____ DNA and the ________ proteins being built. When the proteins of two different organisms are compared, the ____________________ number of differences in amino acid sequences is a clue as to how long ago two species diverged from a shared common ancestor. Genetic Similarities Do the two organisms being compared have the same _______ number of chromosomes? The same type ____ of chromosomes? Two organisms that bear no resemblance to one another anatomically may still be related to one another. Two different “looking” organisms may have similar genes in their DNA. Genetic Similarities Example: Humans have a gene that is the code for building a protein called myosin. This protein is a primary component of our muscles. Yeasts (which have no muscles) have the same gene. The gene in yeasts produces the same myosin protein as it does in humans. In yeasts, this protein is used to move materials around the inside of the cell. This genetic similarity is an indication that yeasts and humans share a common ancestry __________________. Genetic Similarities The more _______ similar the DNA sequences of two species, the more _______ recently they shared a ________________, common ancestor and the more ______ closely they are related. The more two species have diverged from one another, the ________ less similar their DNA will be. __________ Embryological Similarities Similarities in embryological development provide evidence of phylogenetic relationships. HUMAN CHICKEN TURTLE NEWT FISH Some organisms show no similarities as adults, but embryos are very, very similar as ________. Embryological Similarities An Example: An amnion is a fluid-filled sac that surrounds the embryos of some vertebrates. The embryos of fish and amphibians lack an amnion. The embryos of reptiles, birds, and mammals possess an amnion. amnion On the basis of this shared embryological structure, reptiles, birds, and mammals are grouped together and are referred to as amniotes. CLADISTICS Cladistics is a relatively new method of classifying organisms ___________________. Cladistics identifies the characteristics _____________ of organisms that are evolutionary innovations “_____________________.” new characteristics that These “innovations” are ____ arise as living organisms _______________. evolve over time Cladistics uses features called “shared characters” and “derived characters” to establish evolutionary relationships. Shared character: A feature that all members of a group have in common. Examples include … … feathers in birds and hair in mammals. Derived character: A feature that evolved only within the group under consideration. An example of a derived character might be the ______________. feathers in birds Birds are the only animals to have feathers. It is therefore assumed that feathers _______ evolved not inherited within the bird group and were ___________ from a distant ancestor. Shared derived characters are strong evidence of common ancestry between the organisms that share them. Organisms that share one or more derived characters most likely inherited those characters from a common ancestor. CLADES This term is used to describe … … a group of organisms that includes an ancestor plus all of its descendants. Clades do not use the traditional Linnaean category names such as phylum, class, or order. clade can be The relationship between the organisms in a _____ cladogram represented by a diagram called a __________. Cladogram: A diagram that shows the evolutionary relationships among a group of organisms. Constructing a Cladogram This cladogram shows the relationship between 4 groups of living plants alive on Earth today. The other organisms are called the “in-group” and possess one or more of the shared derived characters. A cladogram deliberately includes an organism that is only distantly related to the other organisms. This organism is referred to as the “out-group.” The purpose of the out-group is to serve as a basis of comparison with the other organisms. 4. What is the out-group in this cladogram? 5. What is the in-group in this cladogram? 6. List the derived characters in this cladogram. 7. Do ferns have seeds? Answers on Slide 51 8. List the traits possessed by the flowering plants. Answers to Questions On Slide 50 4. What is the out-group in this cladogram? Answer: Mosses 5. What is the in-group in this cladogram? Answer: Ferns, Gymnosperms, and Angiosperms 6. List the derived characters in this cladogram. Answer: Vascular tissue, seeds, and flowers. 7. Do ferns have seeds? Answer: No 8. List the traits possessed by the flowering plants. Answer: Flowering plants have vascular tissue, seeds, and flowers. Placenta Live birth What are the derived characters shown in this cladogram? Hair Openings in skull for muscles Amniote egg Answer: See Slide 61 Placenta Live birth Which group on the cladogram arose first? Hair Openings in skull for muscles Amniote egg Answer: See Slide 61 Placenta Live birth Do amphibians have an amniote egg? Hair Openings in skull for muscles Amniote egg Answer: See Slide 61 Placenta Live birth Do turtles have an amniote egg? Hair Openings in skull for muscles Amniote egg Answer: See Slide 61 Placenta Live birth Which two groups on the cladogram seem to be most closely related? Hair Openings in skull for muscles Amniote egg Answer: See Slide 61 Placenta Live birth Hair List the groups that have hair. Openings in skull for muscles Amniote egg Answer: See Slide 61 Placenta Live birth Hair List the groups that give live birth to their young. Openings in skull for muscles Amniote egg Answer: See Slide 61 Placenta Live birth Hair What are the derived characters of the monotremes? Openings in skull for muscles Amniote egg Answer: See Slide 61 Placenta Live birth Hair Which two groups have the most shared derived characters? Openings in skull for muscles Amniote egg Answer: See Slide 61 Answers to Questions On Slides 52 - 60 1. What are the “derived characters” shown in this cladogram? Answer: Amniote egg, openings in skull for muscles, hair, live birth, and placenta. 2. Which group on the cladogram arose first? Answer: Amphibians 3. Do amphibians have an amniote egg? Answer: No 4. Do turtles have an amniote egg? Answer: Yes 5. Which two groups on the cladogram seem to be most closely related? Answer: Birds and dinosaurs. 6. List the groups that have hair. Answer: Monotremes, marsupials, and placental mammals. 7. List the groups that give live birth to their young. Answer: Marsupials and Placental Mammals. 8. What are the derived characters of the monotremes? Answer: Amniote egg, openings in skull, hair. 9. Which two groups have the most shared derived characters? Answer: Marsupials and Placental mammals. Kingdoms and Domains As new discoveries have been made, the systems of classification had to be changed. The first attempt at scientific classification was Linnaeus with his __________ 2-kingdom system. Since the time of Linnaeus, many changes have been made in the ways that scientists classify organisms. Plantae Protista Monera Archaebacteria Eubacteria Animalia Plantae Animalia Protista Fungi Plantae Animalia Protista Fungi Plantae Animalia A change to the 5 and 6-kingdom systems is the evidence that all living three broad groups things seem to fall naturally into _________________. In recent years, this led to the establishment of a 3-domain system. Domains are essentially super kingdoms, a taxonomic level even higher than the kingdom level. The 6 kingdoms fall into one of three domains: Kingdom Archaebacteria Kingdom Eubacteria Domain Archaea Domain Bacteria Kingdom Protista Kingdom Plantae Kingdom Fungi Kingdom Animalia Domain Eukarya (all eukaryotes) The domain Archaea contains the Kingdom Archaebacteria. The domain Bacteria contains the Kingdom Eubacteria. The domain Eukarya contains the Kingdoms Protista, Plantae, Fungi, and Animalia. Kingdom Comparison! Domain: Bacteria Kingdom: Eubacteria Cell Type: Prokaryotic Cell Structures: Thick and rigid cell walls composed of peptidoglycans E. coli Cyanobacteria Cell Organization: Unicellular Food Getting: Includes autotrophs and heterotrophs Examples: Strep, Staph, E. coli Staph Strep Kingdom Comparison! Domain: Archaea Kingdom: Archaebacteria Cell Type: Prokaryotic Cell Structures: Cell walls do not contain peptidoglycans. Cell membranes contain unusual lipids not found in any other organisms. “Ancient” organisms. Very primitive. Live in extreme environments. Cell Organization: Unicellular Food Getting: Includes autotrophs and heterotrophs Examples: Methanogens, thermophiles, and halophiles Halophiles: Salt-loving Thermophiles: Heat-loving Kingdom Comparison! Domain: Eukarya Kingdom: Protista Volvox Cell Type: Eukaryotic Cell Structures: Contains organisms that are neither plant, animal, nor fungi. Cell walls composed of cellulose in some organisms. Some have chloroplasts. Ameba Slime mold Cell Organization: Most are unicellular. Some are colonial. Some are multicellular. Food Getting: Includes autotrophs and heterotrophs Examples: Ameba, paramecium, algae, slime molds, giant kelp Paramecium Kingdom Comparison! Domain: Eukarya Kingdom: Fungi Cell Type: Eukaryotic Cell Structures: Cell walls are composed of chitin. No chloroplasts. Cell Organization: Most are multicellular. Some unicellular. Corn Smut Morels Food Getting: Heterotrophs Rusts Examples: Mushrooms, yeasts, puffballs, molds, mildews, smut, and rust. Yeasts Kingdom Comparison! Domain: Eukarya Kingdom: Plantae Cell Type: Eukaryotic Cell Structures: Cell walls are composed of cellulose. Chloroplasts are present. Liverworts Gingko Cell Organization: Multicellular Food Getting: Autotrophs Examples: Mosses, ferns, liverworts, cone-bearing plants, flowering plants. Cones Flowers Kingdom Comparison! Domain: Eukarya Kingdom: Animalia Cell Type: Eukaryotic Cell Structures: No cell walls. No chloroplasts. Cell Organization: Multicellular Food Getting: Heterotrophs Examples: Sponges, worms, mollusks, arthropods, fish, amphibians, reptiles, birds, and mammals Barriers between the species: What factors keep the species apart? A. Physical Characteristics Can this mate with this? Mating is impossible under natural conditions for many organisms. Barriers between the species: What factors keep the species apart? B. Mating occurs, but the offspring do not survive. Bullfrog eggs may be fertilized by the sperm of the leopard frog. The eggs develop to a point, but do not survive. There is too much difference in the chromosomes. Barriers between the species: What factors keep the species apart? C. The offspring may survive but they are not fertile. Example: horse + donkey = mule The mule is sterile and will not be able to reproduce. Barriers between the species: What factors keep the species apart? D. Geographical Barriers Many organisms simply do not come into contact with one another. Barriers between the species: What factors keep the species apart? E. Behavioral Barriers Many organisms, especially in the animal kingdom, will not mate unless certain behaviors are exhibited. Classifying Organisms Using a Dichotomous Key Here are the leaves from seven trees. Use the dichotomous key to classify each leaf. 1 4 2 5 Answers: See Slide 76 3 6 7 Answers to Questions On Slide 75 Answers: 1 – Magnolia 2 – Buckeye 3 – Redbud 4 - Pecan 5 – Birch 6 – Locust 7 – Sweet Gum Created by Amy Brown Copyright © Amy Brown Science All rights reserved by author. This document is for your classroom use only. This document may not be electronically distributed or posted to a public web site, except for intended use in Google Drive and Google Classroom. http://www.teacherspayteachers.com/Store/Amy-Brown-Science