LAB 1

PORIFERA, CNIDARIA, AND PLATYHELMINTHES

 

Animals are multicellular  with regard to cellular organization.  They are eukaryotic with regard to nuclear organization and they are heterotrophic with regard to nutrition.  All animals obtain food by ingestion of organic compounds: either other organisms or their by-products.  Animals are consumers and like all other heterotrophs are dependent on producers which convert solar energy into chemical energy .

 

In this lab, we will examine organisms from the three most primitive phyla of the Animal Kingdom.  Think about the characteristics of broad classification and describe these differences which place the three phyla into different broad groups (Subkingdom Parazoa vs. Eumetazoa, Grade Radiata vs. Bilaterata, and Subgrade Acoelomata, etc.). Refer to your photographic atlas and the black and white line drawings included in this lab to assist with your microscopic identification and study.  Record your observations in your laboratory report.  Draw the microscopic specimen within a circle which represents the microscopic field.  Beneath each drawing label the specimen and the power of magnification used for observation.  Label the anatomical features listed for each specimen.

 

 

1  Compare the anatomy of the representative animals, describing similarities and differences in organs and body form and the lifestyle or niche of the organism.

 

2  Discuss how these similarities and differences may indicate phylogenetic relationships.

 

3  Discuss the relationship between body form and the life style or niche of the organism.

 

 

Prepared Slides:   1  Grantia  l.s. - label spongiocoel, osculum, and ostium

This is a longitudinal section through a common sponge.  The entire section may not fit within your microscope field.  You may need to move the slide to observe both the base of the sponge and the osculum. (Atlas pp. 100-101; text p. 595)

       

                              2  Grantia  spicules - w.m. draw and label spicules.

These spicules are composed of silicon and are unstained.  They are therefore clear and easily overlooked under the microscope.  Reduce the light illuminating the spicules by adjusting the iris diaphragm.  (Atlas p. 100-101)

              

Preserved specimens:

                               1  Leucosolenia ascon type (Atlas p. 100)

                               2  Grantia (Scypha) sycon type (Atlas p. 101)

 3  Commercial  leucon type (Atlas p. 101)

 

 

Prepared slides:   1  Hydra c.s. - label epidermis, mesoglea, gastrodermis,

gastrovascular cavity.  Look carefully for specialized cells called cnidocytes from which the phylum takes its name.

(Atlas p. 103)

 

2  Hydra adult w.m. - label tentacles, cnidocytes, hypostome, mouth, ovary, testes, and bud(s) if present. (Atlas pp. 102-103)

 

3  Obelia hydroid colony - label tentacles, mouth, hydrotheca, nutritive hydranth, gonopore, medusa bud, gonotheca, gonangium. (Atlas pp. 103-104)

    Print Obelia diagram 

 

4  Obelia medusa - label tentacles, cnidocytes, gonad, mouth, manubrium, velum.  (Atlas p. 104)

 

Preserved specimens:

1  Physalia Portuguese Man of War (medusa and polyp colony) (Atlas p. 104)

2  Aurelia  true jellyfish (medusa form) (Atlas p. 105; text p. 597)

                              3  Gonionemus  - medusa

                    4  Metridium - sea anemone (Atlas p. 106; text 597)

                    5  Corals (Atlas p. 106; text p. 597)

 

Living material:  Hydra

Prepare a temporary wet mount of the Hydra culture provided using a depression slide and cover slip.   When finished, wash and dry the slide and coverslip for future use.

 

1  Observe the movement and structure of the Hydra on all

powers.

 

2  After observing the Hydra, add two drops of methyl green solution at the side of the coverslip.  What physical phenomenon will move the dye beneath the coverslips

 

3     Using the high dry objective, observe the discharge of nematocysts.  From

what organelle are the nematocysts expelleds

 

 

 

Prepared slides:   1  Planaria w.m. -  label eyespot, auricle, epidermis,

anterior, and posterior. (Atlas p. 107; text p. 600)

 

2   Planaria digestive - label mouth, proboscis, and intestine.

 

3  Fasciola hepatica - label oral sucker, pharynx, esophagus, ventral sucker, uterus with eggs, ovary, testes, yolk gland.  (Atlas, p. 108)

 

4 Clonorchis  - label oral sucker, mouth, pharynx, esophagus, intestinal caeca, uterus, excretory pore, and testes. (Atlas p. 109)

 

5  Taenia pisiformis - (scolex) - label the rostellum with hooks, sucker, and neck. (Atlas p. 110; text p. 601)

 

6  Taenia pisiformis -(mature, gravid) - label testes, ovary, uterus, longitudinal nerve, longitudinal excretory tube, genital pore, ovarian capsules with eggs ( only in gravid proglottids). (Atlas p. 110)

 

Preserved specimens:  Examine the representative examples of flukes, tapeworms, and flatworms.  Be able to identify these are members of the phylum Platyhelminthes. 

 

Living material:  Planaria

Prepare a temporary wet mount of the Planaria culture provided using a depression slide and cover slip.   When finished, wash and dry the slide and coverslip for future use.

 

SUMMARY TABLE:  ANIMAL SURVEY

Keep this chart up to date as you study individual phyla in the animal kingdom.  This will be a ready tool for comparison of animal groups.

 

ANIMAL	TYPE OF  SYMMETRY	LEVEL OF ORGANIZATION	TYPE OF BODY CAVITY	DIGESTIVE OPENINGS	CIRCULATORY SYSTEM	HABITAT	RESPIRATORY ORGANS
SPONGE
HYDRA
PLANARIA
ROUND- WORM
EARTH- WORM
CRAY- FISH
GRASS- HOPPER
LAN- CELET
FROG
PIG

 

 

 

 

 

 

 

 

ANIMAL	EXCRETORY SYSTEM	LOCO- MOTION	SUPPORT SYSTEM	SEGMENTATION	APPENDAGES	NERVOUS SYSTEM ORGANIZATION
SPONGE
HYDRA
PLANARIAN
ROUND WORM
EARTH WORM
CRAY FISH
GRASS HOPPER
LAN CELET
FROG
PIG