Biology 1102

Lecture four

Slide 1 - Taxonomy

Kingdom

Phylum

Class

Order

Family

Genus

Species

Slide 2 – Examples of taxonomy of animals

Category Haircap moss Red oak House fly Herring gull Wolf Human

Kingdom Plantae Plantae Animalia Animalia Animalia Animalia

Phylum Bryophyta Tracheophyta Arthropoda Chordata Chordata Chordata

Class Musci Angiospermae Insecta Aves Mammalia Mammalia

Order Bryales Fagales Diptera Charadriiformes Carnicora Primata

Family Polytrichaceae Fagaveae Muscidae Laridae Caridae Hominidae

Genus Polytrichum Quercus Musca Larus Canis Homo

Species commune robra domestica argentatus lupus sapiens

Slide 4 – Vertebrates

Slide 5 - Invertebrates

Slide 6 - asymmetry

Slide 7 – Symmetry of animals

Slide 6 – primary tissue layers

-Ectoderm is defined as the outermost of the three primary layers of an embryo; produces the nervous system, the epidermis and epidermal derivatives, and the lining of various body cavities such as the mouth.

-Mesoderm - gives rise to tissue including connective tissue, muscle, circulatory system and gives rise to the notochord and neural tube as well as the urogenital system.

-Endoderm - gives rise to various tissues including the gastrointestinal tracks and endocrine glands

Slide 9 - Coelom

Only animals that develops a mesoderm will develop a coelom

Slide 7 - Body cavities and designs

Slide 10 - Segmented animals – earth worms

Slide 12 – Non-segmented animals

Slide 13 – Sac vs. Tube-within-tube body plan

Slide 12 - Phylum Porifera – Sponge Bob

Slide 14 – Internal structure of a sponge

Slide 16 – Sponge continued

Slide 17 – Sponge reproductive methods Sponges can reproduce either through asexual or sexual

means. Examples of asexual reproduction are given below:

• Fragmentation – small part of the sponge may break away (e.g. accident) and develop into a complete mature organism

• Budding – a small out growth will appear along the side of the sponge and will gradually increase in size

- The outgrowth never really break away from the original organism but will continue to branch out and create a extremely large and complex

organism

Slide 18 – Gemmules of sponges

Gemmules are formed when the environmental conditions gets tough.

The sponge proceed into a semi-dormant phase for protection and could be considered as a form of asexual reproduction. For example:

-The outer cluster of the sponge cells forms a hard outer covering around others

-The clusters inside are dormant and are protected from the environment

-When the conditions are right, the inner cluster of dormant cells began to divide (mitosis) and establish a new colony of sponge

Slide 19 – Sexual reproduction of sponges

Sexual reproduction of sponges proceeds as follows:

• Amoeboid like cells produces both egg and sperm

• The egg and sperm are released into the central cavity and into the surrounding environment

• The egg and sperm are released at different times to insure that there will be no self fertilization (defeating the purpose)

• Once the egg is fertilized a zygote is formed

• The zygote or also could be called a larva (pl. larvae) is mobile and can relocate to a different location and develops into another sessile filter feeder

• Sponges are capable to regenerate a damaged part of itself when needed. Even if it is chopped up or a major piece of its body is lost, new sponges may grow and appear in its place.

Slide 17 - Ctenophora

Slide 18 - Cnidarians

Slide 23 - Cnidocytes and nematocysts

Slide 23 – Cnidarians – distinct life cycles

Slide 24 – Nerve net

                                                                                              

                                       

Slide 25 – Life cycle of a Jellyfish

Slide 26 – Sea anemone

Slide 27 - Class Anthozoa - corals

Slide 28 - Class hydozoa (Portuguese Man of War)

Slide 25 - Class hydozoa - hydra

Slide – 26 - Obelia

Slide 31 - Phylum Nemertea – Ribbon worms

Slide 28 - Phylum Platyhelminthes – class Turbellaria –planarians - flat worms

Slide 33 - Phylum Platyhelminthes - Turbellaria

Slide 29 - Phylum Platyhelminthes - class Trematoda - flukes

Slide 30 - blood flukes

Slide 31 – blood fluke eggs

Slide 33 - class Trematoda - flukes - Schistosoma haematobium

This man has advanced schistosomiasis. Note the distension of the collateral veins due to portal hypertension.

Slide 34 – liver fluke (sheep and moose)

Slide 35 – liver fluke human

Slide 36 – Human liver fluke life cycle

Slide 37 - Phylum Platyhelminthes - Class Cestoda – tape worms

Slide 42 – Human tapeworm lifecycle

Slide 43 – tapeworms in small intestines

Slide 44 – Tape worms and diet

Slide 41 - A nine year-old Brazilian boy, displaying the hookworms and tapeworms he expelled

Slide 38 – tape worm

Slide 39 – Tapeworms

Slide 40 – Tapeworms

Slide 45 - Phylum Nematoda – roundworms - Ascaris

Slide 46 – Ascaris life cycle

Slide 47 - Phylum Nematoda - Trichinella spiralis - Trichinosis

Rectal prolaps

Phylum Nematoda – Trichuris trichiura – Whipworms

Whipworms in the intestines

Embryonated eggs

Slide 49 – Whipworm life cycle

Slide 50 – Nematoda - Onchocera volvulus – Elephantiasis Lymphatic Filariasis

Slide 51 - Filariasis

Slide 52 – Onchocera life cycle