Phyla Porifera & Cnidaria Lab 6

• Lab 6 covers Phyla Porifera and Cnidaria, along with the Lophotrochozoans, as taught in Chapters 28 and 29.
• The formal report due date is March 14 at midnight.
• Submit the report as a single PDF file to the assignment folder on D2L.
• The data for the report is available on D2L.
• Ensure to use the assigned data from your specific lab section when writing a formal lab write up.

Nutrient Experiment - Formal Reports

• Reports should investigate how plants react to the 3 macronutrients: nitrogen (N), phosphorus (P) and potassium (K).
• Formulate specific hypotheses or questions to write the introduction and discussion sections of your lab report.
  • Consider questions like "Why are nitrogen, phosphorus and potassium important?"
  • Explain why barley was chosen as a study organism.
  • Compare how plant organs respond to particular nutrient deficiencies.
  • How your results compare to published scientific papers with similar setups.
• Use remaining lab time to start working through your data to complete your formal report.

Nutrient Experiment - Results Section

• This section is written in past tense.
• State the most significant findings in the first sentence.
• Summarize findings with figures, do not include raw data or irrelevant photos.
• Figures and tables must have a numbered caption and appear after your opening statements

Nutrient Experiment - Figures

• Graphs should be easy to interpret.
• Avoid ambiguous labels.
  • Use (+ctrl, -ctrl, -N, -P, -K) instead of cb3013 treatment 1.
• Labels should be defined in the caption.
• Default graphs in Excel are often unusable.
  • Remove shadows and gridlines.
  • Add accurate error bars.
• Use two graphs: one for root and shoot length vs treatment, and another for %germination vs treatment.

Chapter 28: Kingdom Animalia

• Animals are multicellular with complex tissue types
• Animals are eukaryotic and heterotrophic
• Animal cells lack cell walls
• Sexual reproduction is the primary means of reproduction.
• Animals have a dominant diploid stage, exhibiting a diplontic life cycle.

Body Plans of Triploblastic Animals

• Ectoderm is the outer layer and forms nervous system and epidermis.
• Mesoderm is the middle layer, forming muscle cells and connective tissue.
• Endoderm is the innermost layer, which forms internal organs.

Acoelomates

• Acoelomates lack a body cavity.

Pseudocoelomates

• Pseudocoelomates have a body cavity that is not completely lined by mesoderm

Eucoelomates

• Eucoelomates possess true coelom, a body cavity completely lined by mesoderm.

Body Symmetry

• Types shown include Quadrupedal and Bipedal Vertebrates
• The body can be sectioned into transverse, frontal, and sagittal planes.

Phylum Porifera (Sponges)

• Sponges lack true organs, tissues and systems.
• Sponges have specialized cells, motile larvae, are eukaryotes and heterotrophs, and they lack cell walls.
• Processes occur at a cellular level.

Phylum Porifera Anatomy

• Osculum: Opening through which filtered water is expelled.
• Spongocoel: Hollow inner space of the sponge, is lined with choanocytes.
• Choanocytes: Flagellated cells filter water for nutrients and create a current.
• Ostia: Canals lined with choanocytes, also known as incurrent canals.

Phylum Porifera Basic Body Plans

• Ascon: A simple vase-like structure
• Sycon: Have a thicker body wall folded into radial canals
• Leucon: Most complex, with an extensive canal system

Sponge Diversity

• Lab examples include: Venus flower basket, Bath sponge (Spongilla sp.), and Scphya (Granita) which needs a microscope.
• Characteristics to know are what phylum the individuals belong to (Porifera), and what the phylum's distinctive characterisitics are.

Phylum Cnidaria

• Cnidaria have two germ layers and are diploblastic
  • Gastroderm is one layer, with Ectoderm being the other
• Cnidaria have an Incomplete digestive tract
  • Food is ingested and wastes are expelled through a single opening
• Cnidaria exhibit radial symmetry.
• Nerve nets allow for controlled movement.
• Cnidaria can be dimorphic, existing in two body forms.
• Cnidocytes (stinging cells) are a distinctive feature.
• Cnidaria have specialized cells called cnidocytes, which contain stinging nematocysts.

Cnidaria Diversity - Hydrozoa

• Polyp form is dominant.
• Exhibit a dimorphic life stage involving asexual reproduction in the polyp form and sexual reproduction in the medusa.
• The class can be solitary or colonial.
• SPOTLIGHT ORGANISMS: Physalia physalis (Portuguese man o' war), which is colonial.
  • The top gas-filled bladder organism controls movement, and can deflate to avoid predators.
  • Tentacles can extend up to 165 feet to kill and trap food.

Cnidaria Diversity - Scyphozoa

• Scyphozoans are true jellyfishes
• Medusa stage is dominant, polyp stage is reduced or absent.
• Sexual reproduction produces a zygote that becomes planula larvae.
• Ring and radial canals are ciliated to move food.
• Oral arms bear the stinging cnidocytes, which paralyze prey used for both defense
• Gonads are the sex organs.
• Subgenital pits provide oxygen to gametes.
• SPOTLIGHT ORGANISM: Aurelia spp

Cnidaria Diversity - Anthozoa

• Anthozoa includes flower animals, such as sea anemones.
• Only the polyp form is present.
• Colonial or solitary marine organisms that reproduce sexually and/or asexually. -Includes sea anemones, sea fans, and corals.
• SPOTLIGHT ORGANISM: Metridium sp, a sea anemone found in cooler northern Pacific and Atlantic waters.

Phylum Platyhelminthes Distinctive Features

• Platyhelminthes, are dorsally flattened and called flatworms.
• Exhibit bilateral symmetry with cephalization.
• Acoelomate body plan.
• Monoecious.
• Incomplete digestive system.
• No respiratory or circulatory systems.
• Possess flame cells.

Phylum Platyhelminthes Diversity

• Class Turbellaria (Planaria): Example is Dugesia sp.
• Class Trematoda (Parasitic flukes): Example is Clonorchis sp.
• Class Cestoda (Tapeworms): Example is Taenia sp.
• Differences between the classes are based on life history traits.
• Lab exam question: What features are unique to the class Cestoda due to its parasitic lifestyle?

Planaria Anatomy

• Important anatomical features include: gastrovascular cavity, pharynx, eyespot, auricle, and diverticulum of gastrovascular cavity.
• SPOTLIGHT ORGANISM: Dugesia sp. (Planaria)
  • Free-living flatworm in freshwater habitats known for regenerative capacity.

Phylum Mollusca Distinctive Features

• Molluscs possess four major morphological features: a protective shell, a mantle or sheath of skin, a visceral mass that houses major organs, and a foot for locomotion

Phylum Mollusca Diversity

• Class Gastropoda: snails, slugs & nudibranchs
• Class Bivalvia: mussels, clams, scallops & oysters
• Class Cephalopoda: octopuses, squid, cuttlefish & nautiloids
• Examine the 3 classes and compare and contrast the examples to what makes them similar vs different.

Phylum Annelida Distinctive Features

• Annelids are coelomates with a complete digestive system
• The body is divided into segments called metameres that allow for specialization of body parts and facilitate locomotion.
• Closed circulatory system present.
• Well-developed dorsal brain (cerebral ganglia) and a ventral nerve cord constitute the nervous system.

Earthworm Anatomy

• Lumbricus terrestris (earthworm) is the spotlight organism for dissection.
• External anatomy includes: mouth, segments, seminal groove, clitellum, and anus.
• Internal anatomy includes: pharynx, esophagus, crop, gizzard, intestine, aortic arches (hearts), seminal vesicles, nephridia, seminal receptacles, septa, and cerebral ganglia.

Dissection Safety Notes

• The most effective dissection tool are scissors, scalpels should be used with extreme caution if necessary!
• Never use excessive force or cut toward your hand.
• Only one pair of hands should be present in dissection at any time.
• Broken or dull scalpels should be given to TAs for proper disposal.
• All dissections can be thrown in the garbage.
• Clean your trays, dissecting tools, and stations before leaving

Todays To-Do list

• Chapter 28: Sea Creatures

  • Phylum Porifera
    • Observe sponge diversity
    • Check understanding Questions 1.1-1.3 -Phylum Cnidaria -Observe Cnidaria diversity -Hydrozoa ex. Portuguese man-of-war -Scyphozoa ex. Aurelia (Label display model) -Anthozoa ex. Metridium (Label display dissection)

  -Chapter 29: Lophotrochozoans

  • Phylum Platyhelminthes -Diversity of Platyhelminthes classes Turbellaria, Cestoda and Trematoda -Label Dugseia sp. -Check understanding 1.1 -1.6 -Phylum Mollusca -Diversity of Mollusca (classes Gastropoda, Cephalopoda and Bivalvia) -Match the shell correctly to each class -Check Understanding Questions #3.1- 3.4 -Exercise 29.4 Phylum Annelida -> Earthworm dissection 1-6 (Supplementary DISSECTION MATERIAL IN APPENDIX)
  • Chapter Review Questions #1 (No Rotifera), 2-4, 8, 10

Learning Objectives: Chapter 28 & 29

• Identify gem layers in triploblastic animals.
• Know protostomes vs deuterostomes and give examples.
• Know distinctive features of the phylum in Porifera & Cnidaria.
• Know 3 major body plans (Ascon, Sycon, & Leucon) & Classify the demo organism for each.
• Cnidaria -Know distinct features & examples -Know & differentiate the 4 classes by traits -Recognize common species. -Be able to label the structures of provided models
• Platyhelminthes -Know distinctive features -Know & differentiate the 3 classes -Distinguish demo organism for each.
• Mollusca -Know key characteristics -Know & differentiate the 3 classes -Distinguish demo organism for each.
• Annelida -Know distinctive traits -External & internal anatomy of earthworm

Protostomes vs Deuterostomes

• Members of major taxonomic groups of animals are categorized by how the develop as embryos
• Protostomes- the first opening in the embryo becomes the mouth
• Deuterostomes- the first opening in the embryo becomes the anus, and the mouth develops later

Phylum Cnidaria - Typical Body Forms

• Tentacle and Mouth (Hydrozoa) -Hydropolyp / Medusa (Both) / Anthropolyp - Pharynx
• Two-Body forms (Polyp and Medusa) are equivalent to Dimorphism

Phylum Mollusca

• 90% of Mollusca described to date are in these two classes - Class Gastropoda (Snails) / Class Bivalvia (Clams)

Phylum Annelida - Distinctive Features are Shown Between

• Class Polychaeta (Sandworm) (Bilateral Sym) - Class Oligochaeta(Earthworm) (50/50 Sym) - Class Hirudinea (Leeches) (Radial Sym)