Biology 203 1st Edition Lecture 12 Outline of Last Lecture I. Seeds and PollenII. GymnospermsIII. AnthophytaIV. What are Animals?Outline of Current Lecture I. 3 Features Define and Animal’s Body PlanA. The number of tissue types in embryosB. The type of body symmetryC. The way in which the earliest events of embryo development proceed.II. About FungiIII. Characteristics of FungiIV. ChytridiomycotaV. ZygomycotaVI. GlomeromycotaVII. BasidiomycotaVIII. AscomycotaCurrent LectureI. 3 Features define an animal’s body planA. The number of tissue types in embryosa. Animals can be categorized in 3 ways based on the number of tissues that arepresent in developing embryos:i. No specific tissues!ii. Diploblasts (= two sprouts) - embryos have two types of tissues or germ layers: the ectoderm and endoderm.iii. Triploblasts (= three sprouts) - embryos have three types of tissues or germ layers: the ectoderm, endoderm and mesoderm. b. Porifera – spongesi. No specific tissues but possess numerous types of cellsc. Diploblastsi. These layers give rise to ectoderm (skin/nervous tissue) and endoderm (digestive tract)ii. CnidariansThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.d. Triploblastsi. These layers give rise to ectoderm, endoderm and mesoderm (muscle, bone and circulatory system)B. The type of body symmetrya. Animal can be asymmetrical – no plane of symmetry (sponges)b. Animals with radial symmetry have at least two planes of symmetry. c. Organisms with bilateral symmetry have a single plane of symmetry and “face” their environment in one direction.d. Porifera have no plane of symmetrye. Cnidarians have radial symmetryf. All other phylum have bilateral symmetryC. The way in which the earliest events of embryo development proceeda. Protostome = mouth firstb. Deuterostome = anus firstc. Deuterostomesi. Echinodermata: sea stars, sea cucumbers, sea urchinsii. Chordata: Vertebrates and kind. Protostomesi. Mollusca, Annelida, Platyhelminthes, Nematoda, Arthropodaii. Divided into Ecdysozoa (those that molt) and Lophotrochozoa (have lophophores or trochophore larvae)iii. Lophotrochozoa1. Mollusca2. Annelida3. Platyhelminthesiv. Ecdysozoa1. Nematoda2. ArthropodaII. About Fungia. Closely related to the animals in the clade Opisthokontab. Animals and fungi are both heterotrophic, requiring complex organic molecules, but differ significantly in how they access those molecules:i. Animals ingest, then digest their food internally, using the large surface area of the intestines to absorb nutrientsii. Fungi, grow their mycelia into their food and secrete enzymes to digest it,then use the large surface area to ingest nutrients.iii. Plants make their own food using light, gas and minerals, and they must maximize their light-, gas- and mineral-collecting surface area.c. Fungi and Animals swim by “pushing” with a posterior cilia, while almost all other eukaryotes use anterior cilia to “pull” themselves through fluidsd. Animals and Fungi increase the rigidity of their extracellular matrix using carbohydrate chitin instead of celluloseIII. Characteristics of Fungia. Eukaryotic, major clade Opisthokontab. Vegetative body may be unicellular (yeast) or composed of microscopic threads called hyphae c. Cell walls made of chitind. Fungi “digest, then ingest”e. Advantages:i. Can grow in any direction, over long distancesii. Can invade the interior of food substrates with absorptive filamentsiii. Dispersal of asexually-produced spores allows for additional exploration of habitats f. Fungi are very good at digesting things, which is makes them both good and bad for other living thingsg. Classified in 5 main phyla defined based on how they produce sexual sporesIV. Chytridiomycotaa. Chytrids use filaments to extract foodb. Large spore-filled “pot-shaped” structure gives them their namec. “Chytridion” is Greek for “little pot”d. Generally found in freshwater aquatic environmentse. To move between food sources, chytrids can make cells (zoospores) that can swim!f. Though Chytrids are found all over as “harmless” decomposers, they have recently become famous for causing a disease in amphibiansV. Zygomycotaa. Zygospores form via sexual reproductionb. Filaments of 2 compatible mating types fuse and form a zygotec. Resulting zygospore is resistant to heat, dryness and other dangersd. Zygomycetes also make spores by mitosise. Asexual reproductionf. Zygomycete fungi colonized the land, living in soils as decomposersg. Common causes of food spoilageh. Some are parasites of animalsVI. Golmeromycotaa. Glomeromycetes form mutualisms with the roots of land plants called arbuscular mycorrhizae (AM)b. Plant and the fungi to exchange resourcesc. These associations are found in most land plants, and in fossils over 460 million years old!d. Spores are borne externally of root, on stalkse. Very large for fungal spores, visible with naked eyef. Taxonomy based on spore characteristicsg. Fungi only live a short time after spores germinate unless they find a root to colonizeVII. Basidiomycotaa. Make sexual spores on basidiab. The basidiomycetes include mushrooms and shelf fungic. MANY basidia are found on the underside of a large aboveground organ, e.g. mushrooms and shelf fungid. The majority of the organism’s body is the microscopic filaments in its food sourceVIII. Ascomycetesa. Ascomycetes make spores in a “sac” called an ascusb. An internal structure that contains the spores prior to dispersalc. Asci are found on the top of a cup-shaped organ you have probably seen before (“cup fungi”d. Morels are also in the Ascomycotae. “Yeast” refers to any fungus with a single-celled life stagef. Occurs in both basidiomycetes and ascomycetesg. Some fungi shift between yeast and filamentous formsh. Candida albicans is common in the human gut flora as a yeast, but becomes an infection when it switches to filamentous