Taxonomy

Taxa- categories of classification singular: taxon

Species: binomial naming of organisms. Consists of species name and genus name

Genus:  contains closely related animals

Family: Genera that share related features

Order: contains families with common features

Class: contains orders with common features

Phylum: (plural, phyla) classes with common features

            Division: this term is used with plants and fungi

Kingdom: 5-Kingdoms: Monera, Protista, Fungi, Plantae, Animalia

                 6 Kingdoms: Kingdom monera is divided into Eubacteria and Archaebacteria

 

 

 

Kingdom Monera

Characteristics

Ø      Prokaryotes

Ø      Contain “naked” chromosome consiting of a single DNA molecules without proteins.

Ø      Plasmids- some monerans contains small circular DNA, in addition of the other chromosome.

Ø      Cells walls contain peptidogylcans, polysaccharide with polypeptides

Ø      Movement: Flagella (structurally different than flagellum found in eukaryotic organisms)

                   

 

 

2 Modes of Nutrition: used to classify prokaryotes

1. Autotrophs- Manufacture own organic compounds
1. Photoautrophs use light energy
2. Chemoautrophs use energy obtained from inorganic compounds: ammonia, hydrogen sulfide and most nitrogen compounds

 

 

2. Heterotrophs- obtain energy by consuming organic compounds
1. Parasites- heterotrophic bacteria that obtain energy by living off of a host, mostly likely harmful
2. Saprobes or saprophytes- obtain energy from dead and decaying matter. Often called decomposers

 

 

Obligate aerobes are bacteria that need oxygen

Obligate anaerobes cannot survive in the presence of oxygen

 

 

 

 

 Eubacteria and Archaebacteria

 

Archaebacteria

Major features

1. cell walls lack peptidoglycans
2. Ribosomes are similar to eukaryotes and not other bacteria
3. plasma membranes are structurally different in comparison to all other living things

 

3 groups

1. Thermoacidophiles- love hot and acidic environments, example; volcanic vents. Some members can use hydrogen sulfide.
2. Extreme Halophiles- love salty environments
3. Methanogens—anaerobic, heterotrophic and produce methane gas. Found in swamps, mud, intestines of animals

 

Eubacteria

 

Major Features

1. Classified into one of three shapes:
1. cocci (spherical),  
2. bacilli ( rod shaped) 
3. spirilla (spirals)

 

 

2. Some produce endospores, genetic material surrounded by a protective wall. Can become active when environmental conditions are right.
3. Cell wall: bacteria can be divided into 2 groups according to the cell wall
1. Gram- positive have thick peptidoglycan cell wall
2. Gram-negative have a thin peptidoglycan layer coated with a layer of lipopolysaccharides.

Common Groups:

1. cyanobacteria( old school name: blue-green algae)
1. photosynthetic- chlorophyll a
2. phycobilins- an accessory pigment
3. Important in the nitrogen-fixing process

                                                               i.      Heterocysts-

2. Chemosynthetic bacteria
1. Autotrophic
2. Called nitrifying bacteria because they convert nitrite (NO₂) to nitrate (NO₃^-)
3. Nitrogen-fixing bacteria
1. Heterotrophic
2. Fix nitrogen: Survive in a mutualistic relationship with plants. Plant roots produce nodules(bacterial housing)
4. Spirochetes
1. Move in a corkscrew motion(flagella)

 

 

 

 

Kingdom Protista

 This varied kingdom contains members that are fungus-like, algae-like, and animal-like: can be unicellular or multicellular.

 

 

Algae like (plant like)

1. All are photosynthetic
2. categories are determined by the
1. types of accessory pigments used
2. movement
3. cell wall composition
4. type of carbohydrate used to store energy

 

 

 

Major Phyla

1. Euglenophyta: Euglena  see page 547 Figure 28.3
1. Cell wall contains PELLICLES(protein strips)….lacks cellulose

Demonstrate phototaxis (the ability to move in response of light) due to the presence of an eyespot

2. Contain 1-3 flagella at their leading end(apical end)
3. Contains contractile vacuole and chloroplast

 

 

 

 

2. Dinoflagellates  see page 556 Figure 28.12
1. 2 flagella

 

3. Chrysophyta  (Golden algae)
4. Chlorophyta (Green algae)
1. Contain chlorophylls a and b
2. Cellulose walls
3. Store carbohydrates as starch
4. Believed to be the ancestor of plants
5. Spirogyra

                                                               i.      Spirogyra Conjugation

6. Unicellular or live in colonies
7. Volvox  see page 566 Figure 28.23

                                                               i.      Volvox Colonies

 

 

5. Bacillariophyta ( Diatoms ) see page 561 Figure 28.17

 

 

6. Phaeophyta  (Brown algae)
1. Multicellular
2. Flagellated sperm cells
3. Know the following structures: thallus, holdfast, stipe and blade.
4. Seaweed and kelp see page 546 Figure 28.1d
5. Alternation of generation see page 564 Figure 28.21 (note the terms sporophyte (2n) and gametophyte (n) and the general idea of the process of alternation of generation)

 

 

 

 

7. Rhodophyta  (Red algae)  see page 565 Figure 28.22
1. Contain phycobilins, a red accessory pigment
2. Multicellular

 

 

 

Protozoans (animal like)

1. heterotrophic
2. play different roles in their environment: predator, parasite, or as a saprobe

 

Major Phyla

1. Rhizopoda
1. Amoeba: move by means of pseudopodia. Pseudopodia can engulf food by (phagocytosis) see page 569 Figure 28.26

 

 

 

2. Foraminifera  (forams)  see page 570 Figure 28.28
3. Actinopoda  Radiolarians    see page 569 Figure 28.27b

 

 

4. Zoomastigophora( zooflagellates)
1. Flagellated protozoa
2. Mutualistic species aid in cellulose digestion
3. Parasitic species(ex. Trypanosoma-causes African sleeping sickness) see page 556 Figure 28.11

 

 

 

5. Sporozoans (apicomplexa) see page 557 Figure 28.13
1. Parasitic
2. Produce spores that are transmitted from one host to another. The second host is needed to complete their life cycle
3. Malaria (Life Cycle) is caused by a sporozoan
4. Effects Red Blood Cells

 

 

 

 

6. Ciliophora
1. Contain cilia
2. Most complex of the protozoan:
3. Stentor p. 558 Figure 28.14a
4. Know organelles of the Paramecium , paramecium labeled drawing  see page 558 Figure 28.14c
5. Paramecium Conjugation page 559 Figure 28.15

 

 

 

 

 

 

Fungus like

form  filaments or spore-bearing bodies similar to fungi

Major Phyla

1. Dictyostelids, cellular slime mold see page 571 Figure 28.29
1. 2 stages during life cycle

                                                               i.      spores germinate into amoebas which feed on bacteria

                                                             ii.      when food source is exhausted the amoebas gather together to form a “slug”.  A stalk containing spores is then produced. Spores are released, await favorable environmental conditions.

 

 

2. Myxomycota, plasmodial slime molds see page 572 Figure 28.30
1. Grow as a spreading mass called plasmodium. The Plasmodium feeds off of decaying vegetation
2. Forms a stalk with spore capsule in unfavorable environmental conditions
3. Spores germinate (in favorable environmental conditions) into a haploid amoeba.
4. Haploid amoebas fuse to form diploid cell
5. Diploid cells grows into plasmodium

 

 

3. Oomycota, water molds, downy molds and white rusts see page 561 Figure 28.16 you don’t need to know the cycle…just check out the goldfish
1. Parasitic or saprobes
2. Cellulose cell walls
3. Form hyphae, filaments that secrete enzymes that digest food

 

 

 

Kingdom Fungi

1. Grow as hyphae(singular, hypha) see page 617 Figure 31.1
2. Mycelium, a mass of hyphae
3. Septa(singular, septum) cross walls that divide the filament into compartments
4. Cell walls contain Chitin, not cellulose
5. parasitic or saprobes
6. Parasitic fungi contain filaments called haustoria that penetrate the host

 

 

 

 

Sexual reproduction  see page 621 Figure 31.7

Fungi are mostly haploid except for a temporary diploid stage for sexual reproductive purposes.

1. Plasmogamy- a haploid fungal strain fuses with another haploid strain forming a dikaryon( a single cell with nuclei from 2 strains)
2. Karyogamy- fusing of the dikaryon( the 2 haploid nuclei) producing a diploid nucleus
3. Meiosis restores the haploid condition. Daughter cells develop into haploid spores, which germinate and form hyphae

 

 

 

Asexual Reproduction

1. fragmentation- breaking of hyphae
2. budding- pinching off of a small hyphal outgrowth
3. asexual spores

Divisions/classes

1. Zygomycota see page 620 Figure 31.6

1. Reproduce sexually
2. Zygospores, haploid stage
3. Example: Mycorrhizae- Mutualistic relationship between fungi and roots of plants. The plant provides sugar while the fungus increases the ability of the roots to absorb water and minerals.
4. Example: Bread mold

 

 

2. Ascomycota, sac fungi see page 622 Figure 31.9

1. Reproduce sexually
2. Ascospores, haploid stage
3. Yeast, powdery mildew, truffles, morels

 

 

3. Basidiomycota, club fungi see page 624 Figure 31.11
1. Reproduce sexually see page 625 Figure 31.12
2. Basidiospores, haploid stage
3. Mushroom
4. Fairy ring see page 625 Figure 31.13

 

 

4. Deuteromycota
1. Imperfect fungi
2. No reproductive cycle has been observed
3. Penicillin, molds

 

 

5. Lichens see page 627 Figure 31.16
1. Mutualistic association between fungi and algae. The algae (a chlorophyta or cyanobacteria) provide sugar for photosynthesis. The fungus (ascomycete) provides water and protection from the environment.

 

 

 

 

Kingdom Plantae

Major Divisions

 

Nonvascular plants: lack vascular tissues, phloem and xylem and as result are small and live in moist environments.

1. Bryophyta (bryophytes) page 585 Figure 29.15
1. Mosses, liverworts, and hornworts
2.  Life cycle: Gametophyte is the dominant generation page 586 Figure 29.16. …will discuss in class

 

 

 

Tracheophytes or vascular plants- contain phloem and xylem

 

2. Phyla Lycophyta (club mosses)
1.  most are extinct woody plants
2. Living example: club moss page 590 Figure 29.21a

 

 

 

3. Phyla Spenophyta-most are extinct  page 593
1. Living example: horsetails…hollow, tube like plant that produces spores at the tips.

 

 

 

4. Phyla Pterophyta- ferns page 593 Figure 29.24
1. Produce sori on the underside of fronds. The clusters of sori, called sporangia produce the spores.
2. Fiddleheads
3. Life Cycle of the Fern,   Prothallus

 

 

 

Vascular Seed Plants

           

5. Phyla Coniferophyta- conifers
1. Cone-bearing; male and female cones
2. Gymnosperms- refers to seeds produced in unprotected megaspores near the surface of the reproductive structure, the cone.
3. Pines, firs, redwoods, cedars
4. Fertilization and seed development can take a year

 

 

 

6. Anthophyta, Angiopserms
1.  Flowering Plants

 

 

 

 

Kingdom Animalia

Major Phyla

 

Porifera – sponges page 647 Figure 33.2

·        Filter feeders page 648 Figure 33.3

·        Classified as parazoa (meaning that cells are not organized into true tissues)

 

 

Cnidaria -  hydrozoan, corals, jellyfish, and sea anemones.

·        2 body forms

1. Medusa- floating, umbrella-shaped body with dangling tentacles (jellyfish) page 649 Figure 33.4

                                    2. Polyp-sessile, cylinder shaped body with rising tentacles (Sea Anemone)

·        In some cnidaria the life cycle will include both a medusa and polyp stages.

 

 

Platyhelminthes- acoelomate (lack coelom) flatworms page 652 Table 33.2

            Free-living flatworms- planarians page 652 Figure 33.9

·        Carnivores or scavengers

·        Live in marine and freshwater

 

            Flukes

·        Internal animal parasites or

·        External parasites the suck tissue fluids or blood

 

            Tapeworm

·        Internal parasites that live in the digestive tract of vertebrates

·        Create segments that are independently functional. These segments are for reproductive purposes…break off from each other…like tape..

·        Lack a digestive tract therefore can only use predigested food in the environment.

 

 

Nematoda- roundworms page 661

·        Pseudocoelomate

·        Complete digestion tract

·        Some are soil dwellers that aid in decomposing and recycling nutrients

·        Trichinosis- caused by eating undercooked meat (esp pork) that contains the roundworm Trichini

 

 

Rotifera - rotifers  

·        Microscopic

·        Complete digestion

·        Filter feeders

 

 

Mollusca- snails, bivalves (clams and mussels), octopuses and squids page 658 Figure 33.21

·        Most have shells, though in the case of squids or octopus it can be reduced or absent

·        Complete digestion

·        Coelomate bodies

·        Octopus has an advanced nervous system and a complex brain

 

 

Annelida- segmented worms-leeches and earthworms page 659 Figure 33.23

·        Complete digestion

 

 

Arthropoda- insects, spiders, crustaceans page 663 Figure 33.26

·        Jointed appendages

·        Well-developed nervous system

·        Specialization of body segments

·        Exoskeleton made of chitin

·        See Figure 33.33 page 667 Grasshopper Anatomy

 

 

 

 

 

 

Exhibit 2 kinds of life cycle

1. nymphs (small versions of adult) that change shape and size as they grow into the adult form.
2. metamorphosis – larvae(maggot), pupa(cocoon), adult page 670 Figure 33.34

 

 

Echinodermata- sand dollars, sea urchins and sea stars page 673 Figure 33.37

·        Radial symmetry

·        Most have complete digestion

·        Ancestors are thought to have been bilateral

 

Chordata-animals with the following features page 675 Table 33.7

1.      notochord- a dorsal, flexible rod that provides support. In many animals the notochord is replaced with bone

2.      dorsal hollow nerve cord- basis of the nervous system. In some chordates this will become the brain and spinal cord

3.      Pharyngeal gill slits- in some this becomes the gill slits, while in others the pharyngeal gill slits disappear during embryonic development

4.      muscular tail- an extension at the end of the digestive tract. In humans disappears during embryonic development.

 

 

 

2 Groups of Chordates

1.      Invertebrates

2.      Vertebrates- have vertebrae that enclose the spinal cord