Biological Classification

1. Biological Classification A look at the grouping of living organisms.

2. Classification • Classification is the process of grouping things by their shared traits. • At least 1.7 million different organisms identified on Earth. • Taxonomy is the scientific study of how things are classified. • Carolus Linneaus was a Swedish scientist who came up with classification system for living things in the 1750’s. • He also came up with a way of naming organisms scientifically called binomial nomenclature (2-part name). • The 2 names that identify an organism scientifically are the genus & species. • Organisms in the same genus share similar characteristics. For example: All cats are in the genus Felis. All dogs are in the genus Canis. • Organisms in the same species are so similar that they can mate & produce fertile offspring. • Ex. Of scientific names: (notice that genus is capitalized but species is NOT). • Felis domesticus (house cat), • Felis tigris (tiger), • Canis lobo (wolf) • Homo sapien (man)

3. 1. Sex female---21. Sex male---5    2. Hair color red---Susan    2. Hair color brown or blond---33. Hair color blonde---Jane3. Hair color brown---4    4. Glasses worn---Donna    4. Glasses not worn---Linda5. Pants jeans---Caleb5. Pants slacks---6    6. Hair color black--James    6. Hair color brown--Zach Sample Dichotomous Key Classification uses the following criteria (characteristics) to classify organisms. Structure How it develops in life (Life cycle) DNA 7 Levels of Classification Kingdom Phylum Class Order Family Genus Species Classification Today Dichotomous Key on the Web

4. 6 Kingdoms • 1) Archeobacteria • One celled prokaryotic (no nucleus) organisms that are either autotrophic (make their own food) or heterotrophic (can’t make their own food) • 2) Eubacteria • Similar to archeobacteria except they have different chemical makeup. • 3) Protista • All are eukaryotes (cells with a nucleus). Can be unicellular or multicellular. • 4) Fungi • Except yeasts, all are multicellular heterotrophs. Includes mushrooms & molds. • 5) Plants • 6) Animals

5. Bacteria • There are more bacteria in your mouth than there are people on the Earth. • Bacteria cells are prokaryotes (no nucleus) & they lack other cell organelles (like mitochondria). • Bacteria have 3 cell shapes. (Determined by chemical makeup of its cell wall). • Spherical • Rod shape • Spiral • Bacteria cell structures & functions • Cell membrane – controls movement of materials in & out of cell. • Cytoplasm– gel like material that organelles float in. • Ribosomes – make proteins. • DNA– genetic material loose in the cytoplasm. • Flagella – long whip-like strands that help bacteria move.

6. Bacteria (continued) • Energy needs. • Autotrophes – make their own food. • From the Sun • From chemicals in their environment. • Heterotrophes– don’t make their own food. They consume (eat) other bacteria or materials. • Reproduction • Binary fission – a type of asexual reproduction that resembles mitosis where one cell makes an identical copy of itself. • Conjugation– a type of sexual reproduction where one cell transfers its genetic material to another cell though a thin threadlike material. The cell that receives the new DNA then undergoes binary fission. • Survival • Many bacteria survive by forming endospores – a small thick wall that acts as armor to protect the cell’s DNA from heat, cold, chemicals, etc. • Uses • Some bacteria cause diseases (usually Eubacteria), but most types of bacteria are harmless or even helpful. (They decompose compounds into more useful chemical & some are even used in the food industry).

7. Protista • *Often called the “junk drawer” kingdom because it contains many organisms that don’t easily fit anywhere else. • They all are eukaryotic (have a nucleus). • Almost all live in moist areas. • May be unicellular or multicellular. • Some heterotrophes, some autotrophes. Plant like protist (algae) with flagella

8. Protista (cont.) • 3 basic categories • Animal-like protists – also called protozoans. • Move (in response to food, chemicals or light). • Pseudopods – move by small bulges in the cell membrane. Ex. Amebas. • Cilia – tiny hair-like structures that move in a wave pattern & make bacteria move. Ex. Paramecium • Flagella – whip-like hairs that move the bacteria. • Sporazoans – not characterized by how they move but because they are parasites (organisms that live on & harm another organism called a host.) • Heterotrophic • Unicellular • Plant-like protists (also called algae) • Autotrophic • Make most of Earth’s oxygen (photosynthesis). • Unicellular Ex. Diatoms & euglenas • Unicellular colonies- groups of unicellular protists together (not specialized). • Multicellular- many special cells for different functions. Ex. Kelps & seaweeds. • Fungus – like protists • Heterotrophes • Have cell walls • Reproduce by spores (tiny cells that can grow a whole new organism). Ameba with pseudopod

9. Fungi • Reproduce by spores. • Eukaryotes • Heterotrophes • Grow in warm, moist places. • Cell Structure • Some unicellular Ex. Yeasts • Some multicellular Ex. Molds & mushrooms. • Hyphae – branching, thread-like tubes that make up the body of multicellular fungi. • How the hyphae are arranged determines how the fungus looks.

10. Fungi (cont.) • How fungi eat: • Decomposers • Parasites Ex. Athlete’s Foot Fungus • Reproduction • *Asexual • spores • Budding – no spores produced. A small yeast cell grows from the body of a larger parent cell & then breaks off & lives independently. • Sexual • 2 hyphae grow together & produce spores that are a combination of both parents. A yeast cell reproducing by budding

11. Plants • Plant characteristics: • multicellular • eukaryotic • autotrphes (through photosynthesis) • Most plants have vascular tissue, leaves, roots, & stems. • *Vascular tissueis a system of small tube-like structures that carry water & nutrients throughout the plant & also act to support the plants growing structure. • Plants like mosses without vascular tissue are called nonvascular plants (they also don’t have true roots or stems). • *Leavesarethe place where most photosynthesis takes place because they have the most chloroplasts(organelle that changes light energy to food). • *Stomataare pores in a leaf that allow CO2 in to plant & H2O vapor out. • *Roots are organs that anchor the plant to the ground & absorb nutrients & water from the ground. • *Stemsare organs that carry substances back & forth from roots & leaves. Left: plant basics/Right: vascular tissue

12. Plants (cont.) • Plant groups • Nonvascular plants • mosses • liverworts • Vascular Plants • Seedless • Club mosses (not true mosses). • Ferns • Seeds • Gymnosperms – seeds are in cones or “naked”. Ex. Conifers like pine trees. • Angiosperms – “flowering plants” seeds are protected by covering called a fruit. Ex. Most flowers, grasses, & fruits. Top: pine tree (gymnosperm) Bottom: flower (angiosperm)

13. Plants (cont.) Seed parts • Plant reproduction • Plants reproduce in 2 stages: • Spore stage – tiny organisms cells are produced. • Fertilization – a plant sperm & egg unit to make the genetic information for the new spores. (Sexual reproduction). • zygotesare fertilized eggs. • Embryos are more developed zygotes. • Seeds – a protective covering for the embryo of a new organism. They have 3 parts: • embryo • stored food (endosperm) • seed coat for protection • Cones- thereproductive structures of gymnosperms. There are male & female cones. Male cones have pollen (sperm) & female cones have ovules (eggs). • Flowers – the reproductive part of angiosperms. A flower has both male reproductive parts (Stamens) & female reproductive parts (Pistils).

14. Animals Animal Diversity Web • Animal Characteristics • Multicellular • Cells are specialized (nerve cells, bone cells, etc.). • Heterotrophes • Most reproduce sexually (unite sperm & egg) • Animal Adaptations • Adaptations are characteristics that allow an animal to survive in its environment & reproduce. • Herbivores – plant eaters. • Carnivores – meat eaters • predators – hunt for food • prey – animals hunted for food • Omnivores – eat both plants & meats. • Animals have many specific adaptations that allow them to find food, escape predators & capture prey. Above: Invertebrate (no backbone) animals Below: Vertebrate (backbone animals

15. Animals (cont.) • Animal Classification • There are about 35 phyla in the animal kingdom. • How animals are classified: • Backbones • Vertebrates – animals with backbones.(5% of all species) • Invertebrates – animals without backbones. ( 95% of all species) • Symmetry – how an animal’s body is balanced. • Bilateral symmetry – you can draw a line in an animal & get 2 mirrored halves. • Radial Symmetry – many lines can be drawn & get equal portions. Above: radial symmetry Below: bilateral symmetry

16. Animals (cont.) • Complete metamorphosis • 4 stages • 1.Egg • 2. Larva • 3. Pupa. • 4. Adult • In the larva stage an insect often looks like a worm. • ** In the pupa stage an insect is covered in a protective covering (cocoon). • Incomplete metamorphosis (gradual) • 3 stages. • Egg • Nymph (small version of adult) • Adult Top: complete metamorphosis Bottom: incomplete (gradual) metamorphosis