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Lab Practical Two

Lab 8: Vascular and Nonvascular plants

  • Plant phylogenetic tree

    • Algal Ancestors

      • Relied on water to disperse gametes

      • Limited to aquatic habitats

    • Non Vascular (Ex: mosses)

      • Terrestrial habitat invasion (can now go on land)

      • Still relies on water to disperse gametes

    • Seedless Vascular plants (ex: ferns)

      • Vascular system (they can grow taller)

        • Xylem and phloem

      • Still dependent on water to disperse e gametes

    • Gymnosperms (ex: conifers)

      • Have seeds and pollen grains

      • Gametes dispersed by wind

      • Really large heights and widths

    • Angiosperms

      • Seeds, flowers, and fruits = rapidly growing diversity

      • Outnumber all other plant groups combined

      • Uses animals as pollinators

  • Alternation of Generations

    • Two phases

      • Gametophyte (haploid)

        • Produces gametes

      • Sporophyte (diploid)

        • Produces spores

Types of plants we need to know

  • Non vascular plants

    • Lack vascular tissue

    • Relies on water to transport their gametes (sperm)

    • Gametophyte dominant

      • Moss (Bryophyta)

        • Gametophyte dominant

        • Sporophyte grows in the form of brownish stalks which produce the spores

      • Liverwort (Hepaticophyta)

        • Has pores along upper surface for gas exchange

        • Gemmae cups contain Gemma’s for asexual reproduction

  • Seedless vascular plants

    • Vascular tissue (xylem and phloem)

      • Enables plants to develop the true roots, stems, and leaves

      • Still depends on water for spreading of gametes

    • Sporophyte dominant

      • Lycophyta (club mosses)

        • Sporophyte dominant

        • Vascular tissue allows it to stand upright

        • Possess strobili (cones) which produce spores

      • Psilotophyta (whisk fern)

        • Sporophyte dominant

        • Sporangium located on synangia

      • Sphenophyta (horsetails)

        • Sporophyte dominant

        • Strobili (cones) found at the tips of each stem

      • Pteridophyte (ferns)

        • Sporophyte dominant

        • Individual sporangia typically found on underside of leaves in collections called sori

          • Spores are formed one it

        • Sori sometimes covered by an indusium

  • Gymnosperms (seed plants)

    • Includes cycadophyta, ginkgophyta, and coniferphyta

    • Posses seeds

    • sporophyte dominant

    • Seeds (female gametes) and pollen (male gametes)

      • Has protection for reproductive cells

    • Secondary growth (wood and bark)

      • Allows plants to grow wider and taller

    • DON’T HAVE FLOWERS

      • They have strobili

      • Cycadophyta (cycads)

        • Used to be everywhere, not so much in modern times

        • Have large strobili

          • Female strobili are more round and squat

          • Male strobilus are long and elongated

        • Pollen grains found on/in the cone

      • Ginkgophyta (ginkgoes)

        • Only gymnosperm to cycle leaves with the season

        • Produces large seeds with a fleshy seed coat

          • Looks like a fruit, but it isn’t

          • Fleshy seed coat is part of the sporophyte (2n)

          • The gametophyte within (n) provides nutrition for developing embryo (2n)

      • Coniferophyta (conifers)

        • Includes pines, fir, cypresses, junipers, and redwoods

        • Conifers include the largest and longest lived plants in the world

        • Have strobili (cones)

  • Angiosperms (flowering plants)

    • Seed plants that possess flowers and fruit

    • Most recent group to evolve

    • Flowers and fruit allowed for vast expansion of native range

    • Pollen grains mostly dispersed by pollinators

      • Anthophyta (flowering Plants)

        • Flowers have many different structures

          • Male structure: stamen

          • Female structure: carpels

        • Seeds develop within ovary (carpel)

          • Once seed develops, ovary becomes the fruit of the plant

Lab 9: Fungi

  • Fungi

    • Main eukaryotic decomposes on the planet

    • parasitic

      • Obtains nutrients from living organisms

    • Saprophytic

      • Obtains nutrients from dead organisms (most fungi)

  • Fungal structure

    • Most of the biomass is in their mats of filaments called mycelia

      • Individual mycelia filaments are called hyphae

      • Mycelial morphology allows fungi to grow directly into their food in order to digest it

    • Hyphae

      • Most fundamental fungal units

        • Filamentous strands of cells that can grow to extreme lengths

        • Each fungal cell has a cell wall made of polysaccharide chitin

      • Fairy rings

  • Fungal Feeding

    • Fungi structure utilize external digestion

      • Secrete enzymes that break down organic material

      • Digested food absorbed into the hyphae

    • Some have specialized enzymes that can break down lignin

      • These fungi are the primary decomposers of dead wood in terrestrial environments

  • Fungal Reproduction

    • Reproduce asexually and sexually

    • All fungus can reproduce asexually

      • They are divided into three groups depending on sexual reproduction

  • Yeast Budding

    • Yeasts are unusual in that they are unicellular fungi

    • They reproduce asexually by budding

    • Used for brewing beer, baking bread

  • General life cycle of a fungus

    • They are haploid the whole entire time unless there is a zygote

  • Fungal Groups

    • Chytridiomycota

    • Mucoromycetes (zygomycota)

    • Basidiomycota

    • Ascomycota

  • Mucoromycota (Zygomycota)

    • Mostly soil dwelling saprophytes

    • Some zygomycetes are parasites to plants, insects, and small animals

      • Bread and fruit molds

    • sexual reproduction

      • Forms diploid Zygospores in the zygosporangium that will undergo meiosis yielding haploid zygomycete spores

    • Zygomycota Fungi

      • Rhizopus

        Hyphae

  • Basidiomycota

    • Most familiar fungal group

    • Mainly saprophytic species

      • Mushrooms, toadstools, puffball, shelf fungi, and rusts

    • Sexual Reproduction

      • Formation of specialized club shaped cells called basidium that bear basidiospores

    • Basidiomycota mushroom photos

      Morel

  • Ascomycota

    • Largest fungal group with 64,000 species

      • Morels, molds, lichens, truffles, and single called yeasts

    • Sexual Reproduction

      • Ascocarp contains ascus

        • Theses ascus forms ascospores

    • Ascomycete fungi

      • Aspergillus

      • Penicillum

      • Morel

    • Lichen

      • Mutualistic symbiotic relationship between Cyanobacteria or green algae and a fungus

        • Three growth formations:

          • Crutose

            • Crusty

          • Foliose

            • Looks like leaves

          • Fruticose

            • Looks like shrubs

      • Mycorrhizal Relationships

        • Some fungi form mutualistic relationships with plant roots

          • Plant receives increased surface area of root system for enhanced uptake of water and nutrients

          • Fungus receives carbs and sugars from the plant

        • Mycorrhizae come in two forms

          • ectomycorrhizae

            • forms a sheath and network around the roots

          • endomychorrhizae

            • penetrates root cells

      • Athlete’s Foot Fungus

        • Ascomycota foot fungus that usually grows between the tows or on the bottoms of the foot

          • Causes redness, itchiness, and cracking

          • Diagnosis confirmed through culturing or seeing hyphae under the microscope

      • Parasitic Fungus

        • Can infect living plants

          • Taphrina deformans

            • Infects peach trees

            • Causes leaf curl disease

          • Anthracnose fungi

            • Infects sycamore trees

        • The fungus must infect inside the epidermal cell of the living plant in order to steal nutrients

      • Killer Fungi

        • Cordyceps

          • Genus of parasitic ascomycota

            • Mind controlling fungi, or zombie fungi

        • It’s mycelium invades and eventually replaces host tissue

          • Fruiting body (ascocarp) often sprouting through host tissue

Lab 10: Animal Diversity I (Intro to animals and lophotrochozoans)

  • Animals

    • Multicellular Eukaryotes

    • Heterotrophs (ingest their own food)

    • Different animal phyla are characterized by the arrangement of their body plans

      • Body symmetry, # of embryonic tissue layers, presence/absence of a body cavity, patterns of early embryonic development

      • Animals within the same phylum can be vary from each other even though they may have the same body plan

        • Species are broadly distributed across a variety of habitats

  • Types of Body Symmetry

    • Asymmetry

      • No plane of symmetry

    • Radial symmetry

      • Multiple planets of symmetry

    • Bilateral symmetry

      • Single plane of symmetry

  • Early Embryonic Development Gives Rise to Germ Layers

    • ectoderm

      • Gives rise to skin and nervous system

    • Mesoderm

      • Becomes muscles, connective tissue, skeleton, kidneys, circularity, and reproductive organs

    • Endoderm

      • Cells will form the lining of the gut and major organs derived from it

  • Animal Body plans

    • Acoelomate

      • No coelom, only digestive cavity

        • Coelom: body cavity

    • Pseudocoelomate

      • “Sort of” body cavity

        • Between mesoderm and endoderm

      • Also digestive cavity

    • Eucoelomate

      • True body cavity

      • Also digestive cavity

  • Gametes

    • Sperm and eggs are produced within the gonads of animals through meiosis

      • Gonads: Testes and ovaries

    • Fertilization

      • Egg (n) and sperm (n) unite to create diploid zygote (2n)

    • Fertilization membrane forms after the sperm penetrates the egg, preventing other sperm from contacting the now fertilized egg

      egg

  • Internal Vs External Fertilization

    • Internal Fertilization

      • Eggs and sperm meet inside the body of one of the parents

        • Typically female

      • Females invest more energy into each egg, which limits the number of eggs produced

    • External Fertilization

      • Eggs and sperm are dispersed into the medium (air or water) in hopes that they meet and fuse

      • Gametes and offspring are highly vulnerable to environmental conditions

      • Energy is invested into production of many small gametes rather than large ones in hopes that at least some eggs are fertilized

  • Animal Classification

    • Sponges and cnidarians posses traits of some of the earliest animals on the planet

    • Remaining phyla are grouped into two categories

      • Protostomes and deutoerostomes

    • Sponges

      • Porifera

        • No distinct body plan

        • Lacks tissues, organs, and organ systems

        • Sessile (immobile) filter feeders

          • Found on sea floor of intertidal zones, reefs, and the open ocean

            • They take in food through body and filter out food particles suspended in the surrounding water

        • Porifera Anatomy

          • Water enters the sponge through pores called the optimum

          • Water exits the sponge through the large opening at the tip of the sponge called the osculum

          • Flagellated cells called collar cells (choanocytes)

            • Creates a current by beating their flagella, which draws water in through the ostium and out through the osculum

          • Spicules are structural supports that deter predators

      • Cnidaria

        • Coral, Jellyfish, sea anemones

        • Radial Symmetry

        • Diploblastic (2 tissue layers)

          • Ectoderm

            • Gives rise to skin/body covering

          • Endoderm

            • Gives rise to digestive tract

        • Possess muscle & Nerve tissue

          • This means they can move

        • Have tentacles with cnidocytes (stinging cells) that are used to capture prey

        • Cnidarian Body Plan

          • Two variations on body plan

            • Sessile (immobile) polyp

            • Motile Medusa

          • Polyps adhere to substrates and extend their tentacles, waiting for prey

            • Some sea anemones can detach from substrate and swim away

          • Medusa moves freely in the water via drifting and contractions of bell shaped body

  • Protostomes

    • Members of laphotrocgozoa and ecdysozoa gave many unifying features

      • Undergo Protostomes embryonic development

      • Have bilateral symmetry

        • They are symmetrical about one axis

      • Cephalization

        • An accumulation of nervous system at the head of the animal

      • Triploblastic

        • Have three tissue layers

          • Ectoderm, endoderm and mesoderm

            • Mesoderm gives rise to skeleton, blood, muscle, and organs

      • Functions through organ systems

Two lineages of Protostomes

  • Lophotrochozoa

    • Platyhelminthes (flatworms)

    • Annelida (earthworms)

  • Ecdysozoans (Lab 11)

Types of Lophotrochozoa

  • Platyhelminthes

    • Phylum: Platyhelmintes

    • Common name: flatworms

      • 3 groups: Free living planarians

        • Parasitic flukes, parasitic tapeworms

          • They require a host

    • Acoelomate

      • Lacks a true body cavity

      • Reason why they are flat, not round

    • Incomplete digestive system

      • Characterized by gastrovascular cavity

    • Tapeworms don’t have a digestive system

      • Nutrients diffuse in through epidermis from their host organism

  • Annelida

    • Common name: Segmented worm

    • 3 groups: terrestrial earthworms, freshwater leeches, and marine polychaete worm

    • Eucoelomate

      • Coelom acts as a hydrostatic skeleton, cushioning organs, giving them movement

    • Metameric (segmented)

      • Body is divided into segments called metameres

    • Complete, one-way digestive tract

      • Food enters through the mouth and leaves via butthole

      • One way tube spans entire body

    • Earthworm dissection

  • Mollusca

    • Common Name: Molluscs

      • 4 main groups:

        • Chitons

        • Gastropoda

        • Bivalves

        • Cephalopods

      • Eucoelomate

      • Complete digestive tract

        • Alimentary canal

      • Possess a tongue like structure with rows of teeth

        • Radula

        • Bivalves don’t have a radula, they filter feed

    • Squid

    • Gastropod

    • Bivalve

    • Chiton

Lab 11 - Ecdysozoa

  • Animal Classification

    • Sponges and cnidarians possess traits of some of the earliest animals on the planet

    • The remaining phyla are grouped into two categories based on their embryonic development

      • Protostomes and deuterostomes

  • ecdysozoa

    • Nematoda (nematodes)

    • Arthropoda (insects)

  • Ecdysozoan protostomes

    • Grow by molting an exoskeleton

      • Also called a cuticle

    • Exoskeleton serves for support and protection

      • Not composed of living tissue so it can’t grow and expand to fit the organism

  • Post-Embryonic Development: Incomplete Metamorphosis

    • Incomplete metamorphosis

      • Juvenile stages that resemble adults

        • Differ in size and sexual maturity

      • Ex: Reptiles and mammals

  • Post-Embryonic Development: Complete Metamorphosis

    • Complete Metamorphosis

      • Organisms undergo dramatic transformations in form and ecology as the move from the juvenile stage to adult stage

        • Larval→ adult

      • Ex: Aquatic invertebrates, insects, and amphibians

  • Nematoda

    • Nematodes or roundworms

      • Very small

      • Free living (found in soil or aquatic habitats)

        • Also found as parasites with animals and hosts

      • Caenorhabditis elegans (C. elegans)

        • Model organism used to study cellular differentiation

      • Pseudocoelom and complete digestive tract

      • Not segmented

  • Arthropoda

    • Arthropods

      • Insects, chelicerata (scorpions, spiders), myriapods (centipedes), and crustaceans

      • Growth by ecdysis

      • Characterized by jointed limbs

      • Cuticle made of chitin

    • Subphylum

      • Chelicerata

        • Horseshoe crabs, spiders, ticks, mites, and scorpions

        • Ancient

        • 2 tagma

          • Cephalothorax

          • Abdomen

        • 6 pairs of appendages

          • 1 pair of fanged chelicerae

            • Feeding, defense, copulation, movement, sensory reception

          • 1 pair of pedipalps

          • 4 pairs of walking legs

      • Myriapoda

        • Millipedes and centipedes

        • 2 tagma

          • Head

          • Trunk

        • Paired appendages per trunk segment

        • Centipedes are carnivorous and often poisonous

        • Millipedes are detrivores

          • Feed of dead organic matter

      • Crustacea

        • Lobsters, crayfish, shrimp, crabs, water fleas, isopods (wood lice) and barnacles

        • 2 tagma

          • Cephalothorax

          • Abdomen

        • Unique in that they have 2 pairs of antennae

      • Insects

        • Beetles, grasshoppers, butterflies, bees, flies, cockroaches, etc

        • Most abundant and diverse

        • 3 tagma

          • Head

          • Thorax

          • Abdomen

        • 3 pairs of walking legs

        • Usually have 2 pairs of wings

          H

  • Dissections

    • Crayfish

    • Cricket

Lab. 12: Deuterostomes

  • Similarities between protostome and deuterostome

    • They are eucoelomate

      • Have a true body cavity

    • Triploblastic

      • 3 tissue layers (ectoderm, mesoderm, endoderm)

    • Bilaterally symmetrical

      • Symmetrical about one body axis

  • Embryonic Development

    • Zygote grows through cellular division

      • Allows for various diploid embryonic stages

    • Cleavage of zygote exponentially increasing numbers

    • Solid morula forms

    • Hollows out to become blastula

    • Gastrulation occurs and cells migrate to form the three tissue layers

    • Neurulation leads to development of the nervous system

  • Difference in protostomes and deuterostomes

    • In Protostomes

      • blastopore becomes a mouth first

    • In deuterostomes

      • Blastopore becomes anus first

  • Unifying features of deuterostomes

    • Radial instead of spiral cleavage

    • Indeterminate cleavage

    • Anus forms first

  • Two groups

    • Echinodermata

    • Chordates (includes humans)

  • Echinodermata

    • Sea stars, sea urchins, sand dollars, sea cucumbers

      • As adults, bodies are radially symmetrical

      • Larval forms are bilaterally symmetrical

      • Most have spines extending from their body (Projections of internal endoskeleton

        • Endoskeleton is not bone, Made of calcium carbonate

      • Water-vascular system used for movement

        • Series of internal water-filled canals that end in structures called tube feet

    • Sea star anatomy

      • You can trace the path of water through the water vascular system

        • Madreporite → ring canal → radial canals → ampullae → tube feet

  • Chordata

    • Chordates

      • Defined by 4 key characteristics

        • Notochord

          • Forms part of the vertebral column

        • Dorsal hollow nerve cord

          • Becomes brain and spinal cord

        • Pharyngeal gill slits

          • Become openings to the outside of the body for gas exchange

            • Only seen in embryonic development for terrestrial vertebrates

        • Divided into 3 subphyla

          • Urochordata

          • Cephalochordata

          • Vertebrate

  • Chordata subphylum

    • Urochordata

      • Common name: Tunicates

      • tunicates: sessile (immobile) marine organisms

        • Ex: sea squirts and slaps

      • Display all chordate characteristics only in their larval stage

        • Only have pharyngeal gill slits during adulthood

    • Cehphalochordata

      • Common name: Lancelets

        • small elongated “fish-like” marine invertebrates that lack jaws and sense gains

        • Adults wriggle into the sand, leaving only its anterior end exposed

        • They are filter feeders

    • Vertebrate

      • Common name: Vertebrate Chordates

        • Dorsal Hollow nerve chord

        • Pharyngeal pouches form

          • Aquatic: open into gill slits → gills

          • Terrestrial: gill slits do not form after pharyngeal pouches form

            • Vestigial trait (no function)

        • Notochord

          • Forms vertebral column

            • Surrounds spinal cord

        • Post-anal tail

          • Lost in some species

      • Sub sections of Vertebrae

        • Jawless fishes

          • Myxinoidea

            • Hagfishes

              • No vertebral column

              • Has skull

              • Slime defense mechanism

          • Lampreys

            • Skull and vertebral column

            • Parasitic

        • Jawed fishes

          • Chondrichthyes

            • Cartilaginous fishes (sharks and rays)

            • Vertebral column made of cartilage (not bone)

          • Actinopterygii

            • Ray-finned fishes

            • Bone

            • Operculum (bony flap that covers and protects the gills)

        • Tetrapods

          • Amphibia

            • Transitions to land

            • Aquatic larva

            • Metamorphosis

            • Terrestrial adults

          • Reptilian

            • Terrestrial (mostly)

            • Amniotic eggs

            • Scales

            • Modified reptiles

              • Birds

          • Mammalian

            • Terrestrial (mostly)

            • Placenta

            • Fur

            • Mammary Glands

  • Bullfrog Dissection

  • Rat Dissection