Biology Test 3
Ch 32 What happened in the Cambrian Explosion?
-marks a period of rapid animal diversification -he first large animal fossils with hard, mineralized skeletons date back to this time -A relatively brief time in geologic history (30-50 MY) when large, hard-bodied forms of animals with most of the major body plans known today appeared in the fossil record. This burst of evolutionary change occurred about 535-525 million years ago. No new major phyla since.
Ch 32 Know the common characteristics of all animals.
-Animals are multicellular, heterotrophic eukaryotes with tissues that develop from embryonic layers -Animals are multicellular eukaryotes. Their cells are supported and connected to one another by collagen and other structural proteins located outside the cell membrane. Nervous tissue and muscle tissue are key animal features. -In most animals, gastrulation follows the formation of the blastula and leads to the formation of embryonic tissue layers. Most animals have Hox genes that regulate the development of body form. Although Hox genes have been highly conserved over the course of evolution, they can produce a wide diversity of animal morphology.
Ch 31 What are the different roles of a fungus?
-Decomposers break down and absorb nutrients from nonliving organic material -Parasitic fungi absorb nutrients from living hosts -Mutualistic fungi absorb nutrients from hosts and reciprocate with actions that benefit the host
Ch 32 Describe the earliest ancestor of all animals and why they are thought to be the earliest ancestor?
-Molecular analysis suggests the common ancestor animals likely lived about 770 million years ago -The common ancestor may have resembled modern choanoflagellates -Morphological and molecular evidence
Ch 31 What are the characteristics that you would use to classify an organism as a fungus?
1) Fungi are eukaryotic, non-vascular, non-motile and heterotrophic organisms. 2) They may be unicellular or filamentous. 3) They reproduce by means of spores. 4) Fungi exhibit the phenomenon of alternation of generation. 5) Fungi lack chlorophyll and hence cannot perform photosynthesis. 6) Fungi store their food in the form of starch. 7) Biosynthesis of chitin occurs in fungi. 8) The nuclei of the fungi are very small. 9) The fungi have no embryonic stage. They develop from the spores. 10) The mode of reproduction is sexual or asexual. 11) Some fungi are parasitic and can infect the host. 12) Fungi produce a chemical called pheromone which leads to sexual reproduction in fungi. 13) Examples include mushrooms, moulds, yeast.
Ch 32 Know the unique characteristics of animals.
1) are multicellular 2)Animals are heterotrophic, obtaining their energy by consuming energy-releasing food substances. 3)Animals typically reproduce sexually. 4) Animals are made up of cells that do not have cell walls. 5) Animals are capable of motion in some stage of their lives. 6) Animals are able to respond quickly to external stimuli as a result of nerve cells, muscle or contractile tissue, or both.
Ch 32 What are the common features of fungi and animals?
1) both fungi and animals are without chlorophyll 2) Both are having heterotrophic mode of nutrition (not self synthesizers like plants 3) in both, the cells are eukaryotic with organelles like mitochondrion, ER, Golgi 4) both store carbohydrates as glycogen (reserve food) 5) both are having Chitin; cell wall of fungus is primarily made up of chitin whereas in some animals, chitin is present in the exoskeleton structures of insects, spiders, crustaceans 6) Generally both are multicellular (Exception: Yeast is unicellular)
Ch 33 Describe features/characteristics of the Arthropod and specifically the insects that made the most predominant group in the animal kingdom
A member of the phylum Arthropoda, which includes invertebrate animals such as insects, crustaceans,and arachnids; characterized by having segmented bodies and paired appendages. -hard exoskeleton EX: insects, spiders, millipedes, crabs, scorpions, -myriapods, arachnids, crustanons
Ch 31 What are the features and/or highlights of the different classes/groups of fungi? Give examples.
Cryptomycota:There are both aerobic and anaerobic species -Many species are parasites of protists and other fungi -Cryptomycetes are unicellular and have flagellated spores -Like other fungi, they can synthesize a chitin-rich cell wall Microsporadia: unicellular parasites of protists and animals; microsporidians and their sister taxon (cryptomycetes) are a basal fungal lineage. -synthesize a chitin-rich cell wall -Instead of flagellated spores, they produce spores that infect host cells via a harpoon-like organelle Chytridiomycota: They include species that function as decomposers, parasites, and mutualists -They are found in lakes, soil, and marine habitats including hydrothermal vents Zoopagomycota: They live as parasites or commensal symbionts of animals, or as parasites of other fungi or protists -form filamentous hyphae and reproduce asexually via nonflagellated spores -Those that reproduce sexually form a durable structure called a zygosporangium Mucuromycota: Molds in this group include important decomposers For example, Rhizopus stolonifer is the mold responsible for breaking down bread -Many others live as parasites, pathogens, or mutualists with plants (including some mycorrhizae Ascomycota: commonly called sac fungus. The name comes from the saclike structure in which the spores develop. -They vary in size and complexity from unicellular yeasts to elaborate cup fungi and morels -Ascomycetes include plant pathogens, decomposers, and symbionts Basidiomycota: commonly called club fungus. The name comes from the club-like shape of the basidium. -The phylum is named for the basidium, a cell in which karyogamy and meiosis occurs -Some are mutualists that form mycorrhizae -Others are destructive plant parasites: rusts and smuts
Ch 33 Describe Functions of coelom.
Def: A body cavity lined by tissue derived only from mesoderm. 1)Cushions and protects internal organs 2) Hydrostatic skeleton 3). Internal organs can move and grow independently
Ch 32 What are homeotic genes? How do they contribute to evolution of animals?
Def: are master regulator genes that direct the development of particular body segments or structures. -When homeotic genes are overactivated or inactivated by mutations, body structures may develop in the wrong place—sometimes dramatically so! -Most animal homeotic genes encode transcription factor proteins that contain a region called the homeodomain and are called Hox genes. -Hox genes are turned on by a cascade of regulatory genes; the proteins encoded by early genes regulate the expression of later genes.
Ch 31 What are the structural features that help fungi in absorptive nutrition?
Hypha and Mycelium H-One of many connected filaments that collectively make up the mycelium of a fungus M- The densely branched network of hyphae in a fungus. this is how fungus gets food
Ch 33 Know about nutrition, locomotion, reproduction, and any special features of the groups/phylum
Porifera: Lo: do not move nut: Osculum: a large opening that connects the spongocel to environ. repo:sexually, budding and the regeneration of fragments. special:don't have mouths; instead, tiny pores in their outer walls to water is drawn. Cnidaria: Lo: Medusa (jelly fish and look like one) free swimming -polyps sessile don't move nut:-Cnidarians are predators that use tentacles to capture and consume prey -Tentacles are armed with cnidocytes, unique cells used in defense and prey capture -Nematocysts are specialized organelles within cnidocytes that eject a stinging thread repo: asexual or sexual. special:They are diploblastic with radially symmetrical bodies Lophotrochoza: Lo: Each segment has its own separate set of muscles (run circular and longitudinal in each segment; no cross-striation nut:The rotifers are filter feeders that will eat dead material, algae, and other microscopic living organisms. repo: releasing mass quantities of egg and sperm cells into the water in the hopes that fertilization special: the offspring do not fully detach from the parents; therefore, they resemble a chain. Ecdysozoa: Lo: the body wall muscles are all longitudinal, and their contraction produces a thrashing motion nut:Nutrients are transported by fluid in the hemocoel repo: copulate. The sperm is either delivered to the female's body or is deposited directly onto the eggs as they are released. This trait greatly increases the chances of successful fertilization, and has evolved independently in the vertebrates. special:Phylum Nematoda includes many parasites of plants and animals, including humans Deuterostomia: Lo: tube feet nut: They may be suspension feeders, predators, or scavengers repo: external fertilization special: Have different type of cleavage oppenings
Ch 33 Know the phylum of all animals (from Porifera to mammals) and Specific characteristics of each phylum.
Porifera: (sponges) -they are sedentary, mostly marine animals that range in size from millimeters to meters - their cells are not organized into tissues Cnidaria: - includes diverse sessile and motile forms including corals, hydras, and jellies ("jellyfish") -They are diploblastic with radially symmetrical bodie -The basic body plan is a sac with a central digestive compartment, the gastrovascular cavity -A single opening functions as both mouth and anus -Polyps and medusa -The gastrovascular cavity acts as a hydrostatic skeleton against which contractile cells can work 2 clades Medusozoa and Anthozoa Lophotrochoza: -The clade Bilateria contains Lophotrochozoa, Ecdysozoa, and Deuterostomia -have a coelom and a digestive tract with two openings (mouth and anus) -which have bilateral symmetry and triploblastic development -protostome characteristics. -may be either coelomate or pseudocoelomate (depending on phylum) -true tissues, true organs and true organ systems: integumentary system. digestive system. Ecdysozoa: -are animals with a cuticle, a tough external coat -The cuticle is shed during ecdysis, or molting -Nematodes and arthropods are the largest of about eight ecdysozoan phyla Deuterostomia: -Echinoderms and chordates constitute the clade -echinoderms and chordates -"arrow worms"MarinePlanktonic existenceHooded circlet of spines around mouth -Xenoturbellida,Echinodermata, Enteropneusta,Pterobranchia, Chordata -is the fact that the blastopore (the opening at the bottom of the forming gastrula) becomes the anus, whereas in protostomes the blastopore becomes the mouth.
Ch 32 How are Animals traditionally classified based on symmetry and mode of development
Symmetry -Animals may lack symmetry or may have radial or bilateral symmetry. Bilaterally symmetrical animals have dorsal and ventral sides, as well as head and tail ends. Development -Eumetazoan embryos may be diploblastic (two germ layers) or triploblastic (three germ layers). Triploblastic animals with a body cavity may have a coelom or a hemocoel (or both). Protostome and deuterostome development often differ in patterns of cleavage, coelom formation, and blastopore fate.
Ch 33 Compare coelomate, psuedocoelomate and acoelomate animal
coelomate def:Any animal possesing a fluid filled cavity within which the digestive System is suspended. -correlates with a reduction in body size. -These organisims come with a complete lining called peritoneum derived from mesoderm (one of the three primary tissue layers). The complete mesoderm lining allows organs to be attached to each other so that they can be suspended in a particular order while still being able to move freely within the cavity. psuedocoelomate -An invertebrate having a body cavity that is pseudocoelomate. -(literally "false cavity") which is a fully functional body cavity. Tissue derived from mesoderm only partly lines the fluid filled body cavity of these animals. although organs are held in place loosely, they are not as well organized as in a coelomate acoelomate -any organism that lacks a cavity between the body wall and the digestive tract. -lack coelom -examples of acoleomate organisms include flatworm, fluke, tapeworm, and ribbon worm -They exhibit bilateral symmetry and possess one internal space, the digestive cavity. Acoelomates lack a coelom (do not have a true body cavity.) It is usually filled with cells. Pseudocoelomate has the beginnings of a body cavity, but lacks mesentery (or peritoneum). Coelomate animals have a "true" body cavity or coelom and organs are incased in peritoneal membrane.
Ch 31 How are fungal classes/groups classified?
mode of nutrition 1) Saprophytic - The fungi obtain their nutrition by feeding on dead organic substances. Examples: Rhizopus, Penicillium and Aspergillus. 2) Parasitic - The fungi obtain their nutrition by living on other living organisms (plants or animals) and absorb nutrients from their host. Examples: Taphrina and Puccinia. 3)Symbiotic - These fungi live by having an interdependent relationship association with other species in which both are mutually benefited. Examples: Lichens and mycorrhiza Spore Formation 1) Zygomycetes - These are formed by the fusion of two different cells. The sexual spores are known as zygospores while the asexual spores are known as sporangiospores. The hyphae are without the septa. 2) Ascomycetes - They are also called as sac fungi. They can be coprophilous, decomposers, parasitic or saprophytic. The sexual spores are called ascospores. Asexual reproduction occurs by conidiospores. Example - Saccharomyces 3) Basidiomycetes - Mushrooms are the most commonly found basidiomycetes and mostly live as parasites. Sexual reproduction occurs by basidiospores. Asexual reproduction occurs by conidia, budding or fragmentation. Example- Agaricus 4) Deuteromycetes - They are otherwise called imperfect fungi as they do not follow the regular reproduction cycle as the other fungi. They do not reproduce sexually. Asexual reproduction occurs by conidia. Example - Trichoderma. Reproduction 1) Vegetative reproduction - By budding, fission and fragmentation 2) Asexual reproduction - This takes place with the help of spores called conidia or zoospores or sporangiospores 3) Sexual reproduction - ascospores, basidiospores, and oospores
Know examples of animals with radial/bilateral symmetry, open circulation/closed circulation, triploblastic/diploblastic, protostome/deuterostome, complete/incomplete digestive system,
radical symmetry: Cnidarians - corals, jellyfish, sea anemones -water animals Bilateral symmetry: Echinoderm, choradata- clams, snails, octopuses, crustaceans, insects, spiders, brachiopods, sea stars, sea urchins, worm -If an animal has a head end and a tail end it has? open circulation: Arthropods- insects, spiders, millipedes, crabs closed circulation: Cephalopods- annelids, ,vertebrates triploblastic: Bilarian- Molluscs, worms, arthropods, echinodermata and vertebrates -ectoderm, mesoderm, endoderm diploblastic: Jellyfish, comb jellies, corals and sea anemones protostome: spiders, insects, lobsters, ticks, barnacles deuterostome: Echinodermata- starfish, sea urchins, sea squirts, lancelets, and vertebrates,lamp shells incomplete digestive system: Coelenterata- jellyfish, hydra, and corals. complete digestive system: All mammals, like dogs, cats, and humans; reptiles, amphibians, fish, birds, and even insects
