Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Introduction to the Kingdoms of Life Chapter 19 Table of Contents Section 1 Introduction to Kingdoms and Domains Section 2 Advent of Multicellularity Section 3 Complex Multicellularity

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu The Three Domains of Life Biologists have adopted a classification system that divides all organisms into three superkingdoms, or domains. The domain thought to be the oldest is Bacteria, which is composed of the organisms in the kingdom Eubacteria. Archaea is the second prokaryotic domain and is also composed of a single kingdom, Archaebacteria. A third domain, Eukarya, contains all four of the eukaryotic kingdoms: Animalia (animals), Fungi (fungi), Plantae (plants), and Protista (protists). Section 1 Introduction to Kingdoms and Domains Chapter 19

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Three Domains of Living Organisms Section 1 Introduction to Kingdoms and Domains Chapter 19

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Six-Kingdom System of Classification Section 1 Introduction to Kingdoms and Domains Chapter 19

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Bacteria Section 1 Introduction to Kingdoms and Domains Chapter 19 1  m 2  m 5  m (a) Spherical (cocci)(b) Rod-shaped (bacilli)(c) Spiral

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu The Domain Bacteria Characteristics of Bacteria Bacteria have strong exterior cell walls made of peptidoglycan, a weblike molecule complex made of carbohydrate strands cross-linked by short peptide bridges. Unlike the genes of eukaryotes and archaebacteria, bacterial genes have no introns. The amino acid sequences of the ribosome proteins and RNA polymerases found in bacteria differ from those found in eukaryotes or in archaebacteria. Section 1 Introduction to Kingdoms and Domains Chapter 19

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Kinds of Bacteria Bacteria are the most abundant organisms on Earth. Chemoautotrophs, photoautotrophs, and heterotrophic. Section 1 Introduction to Kingdoms and Domains Chapter 19 (a) Gram-positive. Gram-positive bacteria have a cell wall with a large amount of peptidoglycan that traps the violet dye in the cytoplasm. The alcohol rinse does not remove the violet dye, which masks the added red dye. (b) Gram-negative. Gram-negative bacteria have less peptidoglycan, and it is located in a layer between the plasma membrane and an outer membrane. The violet dye is easily rinsed from the cytoplasm, and the cell appears pink or red after the red dye is added. Figure 27.3a, b Peptidoglycan layer Cell wall Plasma membrane Protein Gram- positive bacteria 20  m Outer membrane Peptidoglycan layer Plasma membrane Cell wall Lipopolysaccharide Protein Gram- negative bacteria

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu The Domain Archaea Characteristics of Archaebacteria The cell walls of archaebacteria do not contain peptidoglycan, as the cell walls of bacteria do. Archaebacteria contain lipids very different from those of bacteria or eukaryotes. As with the genes of eukaryotes, the genes of archaebacteria are interrupted by introns. Section 1 Introduction to Kingdoms and Domains Chapter 19

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu The Domain Archaea, continued Kinds of Archaebacteria Methanogens obtain energy by combining hydrogen gas, H 2, and carbon dioxide, CO 2, to form methane gas, CH 4. A group of extremophiles called thermophiles lives in very hot places—up to 106ºC. Halophiles inhabit very salty lakes that can be three times as salty as seawater. Nonextreme archaebacteria grow in all the same environments that bacteria do. Section 1 Introduction to Kingdoms and Domains Chapter 19

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu The Domain Eukarya Characteristics of Eukarya All eukaryotes have cells with a nucleus and other internal compartments. True multicellularity, in which the activities of individual cells are coordinated and the cells themselves are in contact, occurs only in eukaryotes. Eukaryotes have a life cycle that involves sexual reproduction. Section 1 Introduction to Kingdoms and Domains Chapter 19

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu The Domain Eukarya, continued Kinds of Eukarya Protista contains both unicellular and multicellular organisms, many of which are aquatic. Fungi are a group of heterotrophs that are mostly multicellular. Fungi are composed of cells with cell walls of chitin. Almost all plants are autotrophs and have cells with cell walls composed of cellulose. All animals are heterotrophs composed of cells that do not have cell walls. Section 1 Introduction to Kingdoms and Domains Chapter 19

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Kingdom and Domain Characteristics Section 1 Introduction to Kingdoms and Domains Chapter 19

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Advent of Multicellularity Objectives Contrast the terms colony and aggregate. List the characteristics of protists. List the characteristics of fungi. Chapter 19

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu The Many Forms of Multicellularity Colonies Occasionally, the cell walls of bacteria adhere to one another. These formations cannot be considered truly multicellular, however, because few cell activities are coordinated. Such bacteria may properly be considered colonial. A colonial organism is a group of cells that are permanently associated but that do not communicate with one another. Section 2 Advent of Multicellularity Chapter 19

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu The Many Forms of Multicellularity, continued Aggregations An aggregation is a temporary collection of cells that come together for a period of time and then separate. For example, a plasmodial slime mold is a unicellular organism that spends most of its life as single-celled amoebas. When starved, however, these cells aggregate into a large group. This weblike mass produces spores, which are then dispersed to distant locations where there may be more food. Section 2 Advent of Multicellularity Chapter 19

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu The Many Forms of Multicellularity, continued True Multicellularity A multicellular organism is an organism composed of many cells that are permanently associated with one another. Multicellularity enables cells to specialize in different functions. These cells grow and undergo differentiation, the process by which cells develop a specialized form and function. Section 2 Advent of Multicellularity Chapter 19

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Kingdom Protista Members of the kingdom Protista, protists, are defined on the basis of a single characteristic: they are eukaryotes that are not fungi, plants, or animals. Many are unicellular; in fact, all single-celled eukaryotes (except yeasts) are protists. Protists normally reproduce asexually by means of mitotic cell division. Section 2 Advent of Multicellularity Chapter 19

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Kingdom Protista, continued Kinds of Protists Amoebas are protists that have flexible surfaces with no cell walls or flagella; they move by using extensions of cytoplasm called pseudopodia. Many protists, including autotrophs and heterotrophs, move by using flagella. Diatoms are photosynthetic protists with unique double shells made of silica, like boxes with lids. Section 2 Advent of Multicellularity Chapter 19

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Kingdom Protista, continued Kinds of Protists Algae are photosynthetic protists and are distinguished by the kinds of chlorophyll they contain. Slime molds and water molds are often confused with fungi because they aggregate in times of stress to form spore-producing bodies. Sporozoans are nonmotile unicellular parasites that form spores. Section 2 Advent of Multicellularity Chapter 19

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Kingdom Fungi The bodies of fungi consist of long strands of cells that are connected end to end and that share cytoplasm. The slender strands of fungi are called hyphae. Like plants, fungi do not move from place to place. Like animals, fungi are heterotrophs. Fungi are composed of cells with cell walls of chitin. Section 2 Advent of Multicellularity Chapter 19

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Kingdom Fungi, continued Kinds of Fungi Zygomycetes form structures for sexual reproduction called zygosporangia. Section 2 Advent of Multicellularity Chapter 19

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Ascomycetes form sexual spores in special saclike structures called asci.

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Kinds of Fungi Basidiomycetes include fungi that make mushrooms..

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Complex Multicellularity Objectives Identify and classify plants based on characteristics. Discuss the different types of plant cells. Describe the different types of plants: Bryophytes, tracheophytes. Chapter 19

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Kingdom Plantae Plants are complex multicellular autotrophs; they have specialized cells and tissues. Most plants have vascular tissue, which is made up of specialized cells that play a role in transporting water and dissolved nutrients. Plants are sources of food for humans and other animals. Section 3 Complex Multicellularity Chapter 19

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Vascular Tissue Systems in Plants Section 3 Complex Multicellularity Chapter 19

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Types of Plant Cells Section 3 Complex Multicellularity Chapter 19

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Plant tissues are made of three basic cell types. Parenchyma cells are the most common plant cell type. –store starch, oils and water –help heal wounds to the plant –have thin flexible walls

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu –they are strong and flexible. –celery strings are strands of collenchyma. –they have unevenly thick cell walls. Collenchyma cells provide support to a growing plant.

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu –second cell wall hardened by lignin –die when they reach maturity –used by humans to make linen and rope Sclerenchyma cells are the strongest plant cell type.

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Kingdom Plantae, continued Kinds of Plants Plants without a well-developed system of vascular tissues are called nonvascular plants. Mosses are the most familiar example of nonvascular plants. Plants with a well-developed system of vascular tissues are called vascular plants. Their larger, more- complex bodies are organized into roots, stems, and leaves. Most plants are vascular plants. Section 3 Complex Multicellularity Chapter 19

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Kingdom Plantae, continued Kinds of Plants Ferns are the most common and familiar seedless vascular plants. They reproduce with spores that are resistant to drying. Gymnosperms are vascular plants that reproduce using seeds but do not produce flowers. Most plants that produce seeds also produce flowers. Flowering plants are called angiosperms. Section 3 Complex Multicellularity Chapter 19

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Types of Seedless Vascular Plants Section 3 Complex Multicellularity Chapter 19

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Kingdom Animalia Animals are complex multicellular heterotrophs. Almost all animals (99 percent) are invertebrates; that is, they lack a backbone. Of the more than 1 million living species, only about 42,500 have a backbone; they are referred to as vertebrates. Section 3 Complex Multicellularity Chapter 19

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Invertebrate Section 3 Complex Multicellularity Chapter 19

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Vertebrate Section 3 Complex Multicellularity Chapter 19

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Kinds of Vertebrates Section 3 Complex Multicellularity Chapter 19

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Kingdom Animalia, continued Kinds of Animals Animals can range in size from 0.5 mm (0.02 in.) microscopic mites that live on your skin to enormous whales, which are vertebrates, and giant squids, which are invertebrates. The many kinds of animals can be roughly grouped into six categories. Sponges are the only animals that do not have tissues, but they do have specialized cells. Section 3 Complex Multicellularity Chapter 19

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Sponges Section 3 Complex Multicellularity Chapter 19

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Kingdom Animalia, continued Kinds of Animals Cnidarians are mostly marine animals; they include jellyfish, sea anemones, and corals. Mollusks have a saclike tissue called a coelom that encloses internal organs. They include snails, oysters, clams, octopuses, and squids. A variety of animals with cylinder-shaped bodies, called worms, live in both aquatic and terrestrial habitats. Section 3 Complex Multicellularity Chapter 19

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Characteristics of Cnidarians Section 3 Complex Multicellularity Chapter 19

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Characteristics of Mollusks Section 3 Complex Multicellularity Chapter 19

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Types of Mollusks Section 3 Complex Multicellularity Chapter 19

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Kingdom Animalia, continued Kinds of Animals Arthropods have an external skeleton. They also have jointed appendages, such as antennae and jaws. Two-thirds of all named species of animals are arthropods, most of them insects. Echinoderms, a group of invertebrates includes sea stars, sea urchins, and sand dollars. Vertebrates have an internal skeleton made of bone, a vertebral column (backbone) that surrounds and protects the spinal cord, and a head with a brain contained in a bony skull. Vertebrates include mammals, fish, birds, reptiles, and amphibians. Section 3 Complex Multicellularity Chapter 19

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Characteristics of Arthropods Section 3 Complex Multicellularity Chapter 19

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Types of Arthropods Section 3 Complex Multicellularity Chapter 19

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Characteristics of Echinoderms Section 3 Complex Multicellularity Chapter 19

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Types of Echinoderms Section 3 Complex Multicellularity Chapter 19

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Kingdom Animalia, continued Ecological Roles Some animals are detritivores, animals that feed on waste and dead tissue. Other animals, such as buffalo that eat grass, are primary consumers. Many animals, such as humans, bears, and lions, are secondary consumers that eat primary consumers. Finally, some animals, such as intestinal worms, act as parasites and may cause disease in other animals. Section 3 Complex Multicellularity Chapter 19