Chapters 31 and 32

Fungi and Eumetozoans

Chris Lysuik

Kyle Kurihara

Geoff Whitener

etc.usf.edu

Fungi

How do fungi acquire nutrients?They absorb nutrients from the ground by secreting digestive enzymes.

Because of this mode of nutrition, fungi have evolved what structure to provide for both extensive surface area and rapid growth?Fungi have evolved hyphae, (mycelium when underground) a network of tiny filaments composed of tubular cell walls surrounding the plasma membrane and cytoplasm of the cells.

Fungi

How do the cell walls of fungi differ from the cell walls of plants? They contain chitin, a strong flexible nitrogen containing polysaccaride that is also found in the external skeletons of insects and other arthropods, and septum cross walls.

How do fungi contribute to an ecosystem?They keep it stocked with inorganic nutrients essential for plant growth, they share relationships with plants, algae, cyanobacteria, and animals, promoting vigorous growth.

Fungi

Give some examples of how fungi are important to humans.

Without fungus, agriculture would be far less productive. Yeast commonly used as baker’s yeast and brewer’s yeast. Fungi are also used in medicine, like penicillin and also insulin.

Fungi: Chart C

Chytrids

Zygomycetes

Ascomycetes

Basidiomycetes

-Flagellated Spores (zoospores)

-no true mycelium

-Allomyces sap (water mold

-S. endobioticum

-zygosporangium (diploid nuclei carrier)

-sporangium

-R. stolonifer (bread mold)

-Pilobolus

-Asci (sac), ascocarp (fruit bodies)

-Conidia spores

-truffles

-N. crassa (mold)

-Basidiocarp (fruit bodies)

-Basidium(hold spore)

-shelf fungi

-puffballs

Fungi Pictures

Fungal Hyphae

Microbeorganics.com

Penicillin Mold

hss.sas.upenn.edu

Eumetazoans

Outline the major characteristics Campbell uses to define an animal.Nutritional Mode, Cell Structure and Specialization, and Reproduction and Development

List an hypothesis for the origin of animals.The ancestors of animals diverged from the ancestors of fungi as far as 1.5 billion years ago; animals probably evolved from colonial flagellated protists.

Eumetazoans

Describe the two forms of symmetry of the Eumetazoa.

Radial Symmetry:  Any imaginary cut through the center of the animal will divide it into mirror images. 

Bilateral Symmetry: Animals with a left side and a right side.  Only one imaginary cut divides the animal into mirror-image halves.

Eumetazoans

What is the significance of cephalization as an evolutionary trend?Cephalization is the concentration of the central nervous system in the head; it allows bilaterally symmetric animals to be more active and coordinated.

How do the germ layers of Radiata and the other Eumetazoa differ?The Radiata only have 2 germ layers, the endoderm and ectoderm.  The other Eumetazoa have 3 layers, the endoderm, ectoderm, and mesoderm.

Eumatazoans

Acoelomates- Triplobastic animals lacking coeloms Pseudocoelomates- Triplobastic animas with a body

cavity formed from the blastocoel called "pseudocoelom"

Coelomates- Animals that possess a true coelom Protostomes- Original embryonic dent becomes the

mouth of Protostomes and the anus is formed later Deuterostomes- Original embryonic dent becomes the

anus of Deuterostomes and the mouth is formed later

Eumetazoans

Spiral, determinate cleavage- Planes of cell division are diagonal to the vertical axis of the embryo.  The development of the embryonic cell is very easily determined

Radial, indeterminate cleavage- Cleavage planes are parallel or perpendicular to the vertical axis of egg.  Cells produced by early cleavage division retain the capacity to develop into a complete embryo. 

Blastopore- The indentation that leads to the formation of the archenteron.

Eumetazoan Examples

Arthropoda

Mollusca

Nematoda

Protostomia Deuterostomia

EchinodermataChordata

CnidariaCtenophora

Radiata

Eumetazoans

List a number of the major differences between the Protostomes and the Deuterostomes.-Embryonic development:  Mouth formed from initial dent in Protostomes while the anus is formed from the initial dent in the Deuterostomes.-Protostomes have determinant cleavage while Deuterostomes have indeterminate cleavage.  -Protostomes go through schizocoelous development while Deuterostomes go through enterocoelous development.

The End