Biology Midterm 3 Important Vocab PDF

Midterm 3: ***Generalized life cycle of fungi*** Sexual: A haploid enters **Plasmogamy** which is the fusion of cytoplasm which then takes the heterokaryotic unfused nuclei to **Karyogamy** which is when the fusion of these nuclei occurs. A zygote is then produced and is immediately taken into **m...

Midterm 3: ***Generalized life cycle of fungi*** Sexual: A haploid enters **Plasmogamy** which is the fusion of cytoplasm which then takes the heterokaryotic unfused nuclei to **Karyogamy** which is when the fusion of these nuclei occurs. A zygote is then produced and is immediately taken into **meiosis**, which produces spores, and undergoes germination the **mycelium** then starts over again Asexual: however the mycelium in asexual reproduction produces spores and undergoes germination and continues this process. Fungi always have a **haplontic lifecycle,** which is when the **zygote** immediately goes under meiosis **Haploid** and **diploid** are stages in a lifecycle ***The evolution of the seed:*** A seed is an embryonic plant enclosed in a protective outer covering and stored food, protection, doesn't produce offspring right away, only grows under ideal environments, extremely effective Advantages of having seeds: 1. The ability to protect reproduction efforts and the embryo 2. Dispersal, sends the seed off to colonize Gametophyte reduction: An example of these are pine trees with a waxy layer which are protective and adaptive. - It has both early and late evolution - Sporophylls evolved innovations for dry environments, but gametophytes did not - Gametophytes reduced are dependent on sporophytes, they protect from desiccation ALL seed plants are heterosporous which means that they produce two types of spores MOST seedless plants are homosporous, meaning they only produce one type of spore. Gymnosperms: - Are exposed and not in an ovary (naked seeds such as a pine cone( conifers)) - Has sporophylls which are modified seeds - Pollination therefore occurs when it opens up and germinates ( fertilizes), closes protective layer, with a seed inside and germinates. **Homosporous spore production: such as most seedless vascular plants** Sporangium on sporophyll, then a single type of spore, typically a bisexual gametophyte( will have eggs and sperm) **Heterosporous spore production: such as all seed plants** Megasporangium on megasporophyll, then megaspore, to female gametophyte to egg Microsporangium on microsporophyll, then microspore, to the male gametophyte, to the sperm **Megaspores and their production:** - **An ovulated cone is a cluster of megasporophylls** - Ovules are integuments and megasporangium - Megasporocytes produce 4 haploid megaspores but only 1 survives - If the megaspore is not dispersed then the female gametophyte develops within the megasporangium **Microspores and their production:** - **A pollen cone is a cluster of microspores** - Microsporocytes produce 4 haploid microspores - Microspores mature as pollen grains and 2 celled male gametophyte sporopollenin wall Gymnosperm diversity: **There are 4 major groups:** - **Cycadophyta** - **Gnetophyta** - **Ginkophyta** - **Coniferophyte ( 600 extant species, live in the northern hemisphere)** **From ovule to seed in gymnosperms:** Unfertilized egg, fertilized egg, gymnosperm seed that consists of sporophyte embryo and a food supply, and protective seed coat from integument (megasporangium dries out and collapses) **Angiosperms:** Angiosperms produce flowers and seeds in fruits, the flowers are special structures for sexual reproduction **Septals:** protect developing flower **Petals**: help attract pollinators **Stamens:** modified microsporophyll (filaments and anthers) ( male) Carpals: modified megasporophylls (stigma, style, and ovary) (female) **Fruit:** Fruits are fertilized ovules that mature into seeds, surrounding ovary then develops into fruit and protects developing or dormant seeds and aids in dispersal **Angiosperms lifecycle:** Located on the anther there are microsporangium which contains microsporocytes that divide by meiosis-producing microspores, they then develop into a pollen grain which comes out the stigma and style when a zygote is produced by double fertilization where one sperm and egg form a zygote and the other sperm fertilizes a central cell forming endosperms which is a food supply, the endosperm and the seed coat then protect the zygote. When the seed germinates it becomes a mature sporophyll **Angiosperm diversity:** **4 major groups:** 1. **Basal angiosperm \~100 species, oldest lineage ( water lilys)** 2. **Magnolids\~8000 species (black pepper)** 3. **Monocots- ¼ angiosperms\~ 70 000 species (orchids)** 4. **Eudicots\~170000 species, 2/3 angiosperms arthis (peas)** **Fungi:** **Unikonta:** - Includes certain amoebae - Heterotrophic - Most single flagellum on the posterior end The fungi among us: Absorptive heterotrophs that digest outside of the body (**Phagocytosis)** They do this by **releasing enzymes** to digest the complex molecules then absorb smaller molecules. - **Fungus are hyphae that secrete enzymes to gather nutrients** and are specialized for reproduction/spore formation, where haploid cells, or spores, are produced *Trophic phase:* - Hyphae network or the mycelium around or in the food source *Reproductive phase:* - Fruiting bod - Produces spores **Ecological roles:** - Fungi decompose organic matter - They act in symbiotic relationship ( arbustules enhance nutrient uptake) - Arbuscules are mutualistic and parasitic fungi that grow in specialized hyphae **Economic roles:** - Edible - Production of cheeses, bread, wine and beer - Antibiotics **Negative effects:** - Spoil or decompose cloth, food crops, wood, parasites in plants and animals - Parthenogens cause health problems - Foot fungi - White-nose syndrome - Take up 965 hectares - Hundreds of tons - And 1900 years old - 1000 species of chytrids - Ubiquitous in lakes and soil - Decomposers but also parasitic ( like the white worms in wellingtons tank) these are protists, other fungi and plants and animals - Batrachochytrium dendrobatidis is likely responsible for the global decline of amphibians - Some live in the digestive tract of sheep/ cattle and perform important digestive roles **Zygomytes:** - 1000 species - Many are fast growing and responsible for food moulds - Some parasitic or commensal symbionts **Glomeromycetes:** - Only \~160 species, but ecologically significant - **Almost all form arbuscular mycorrhizae** - **80% of plants have mutualistic relationships with glomeromyctes** **Ascomycetes:** - 65,000 species - Includes yeasts, cup fungi, truffles, and morels - Many plant pathogens - Decomposers - pharmaceuticals - Food - **Trophic phase: haploid hyphae (except yeasts)** - **The fruiting body is called the ascocarp** - **Spores produced in asci which are saclike structures and discharged** **Basidiomycetes:** - 30,000 species - **Includes shelf fungi, mushrooms, rusts and puffballs** - Decomposers of wood ( lignin) - **The trophic phase is haploid and dikaryotic** - **The fruiting body is called the basidiocarp which is also dikaryotic** **Lichen** - Lichen is a unique group of organisms with a symbiotic relationship between two or more organisms of fungi. **Asocarp:** - **Very diverse (crustose, foliose, fruticose)** - **Cyanobacteria can be included in symbiosis and change the colour** - Fungi are opisthokonts with cell walls composed of chitin - Fungi are heterotrophic and feed by absorption - Reproduction can be asexual such as budding, spores, and filaments) or sexual ( involves plasmogamy and karyogamy) - There are approx. 100,000 species of fungi currently recognized - **Animals and choanoflagellates share the same lineage** - **They are multicellular heterotrophic eukaryotes ( ingest and digest)** - **Lack cell walls so they rely on proteins external to the cell membrane for support and cell connection, also have collagen found in both animals and choanoflagellates** - **Most animals are capable of rapid movement** **Metazoa:** Reproduction can be both sexual and asexual - **Asexual reproduction occurs** in afew groups such as **budding, fragmentation, fission, and parthenogenesis** - **Sexual reproduction cycles** typically are **diplontic with oogamy which means different size gametes** - **Zygote undergoes** a set **development pattern**, and **tissues produced from embryotic germ layers** **Proferia:sponges** - **Proferia is a colony of specialized cells that lack true tissue and have suspension feeders** - The suspension feeders are when water goes into spomgcoel and out through the osculum - **Chanoocytes or collar cells phagocytize food particles** - The amoebocytes have more nutrients that the other cells and manufacture spicules - Hermaphrodites **Eumetazoa:** - In this group, there is true tissue, tissue is a group of cells united in common structure and/or function - Muscle and nerve tissue central to the animal lifestyle **Development of eumetazoa:** - Cleavage: this is when a mitotic cell divides without cell growth, which typical results in the blastula which is a multicellular hollow ball - Gastrulation: this is layers of the embryotic germ tissues that form tissues and organs that are then produced **Diploblasts:** - In diploblasts there are two germ layers 1. Ectoderm: which is the outer covering or better known as the dermis, and in some groups the central; nervous tissue 2. Endoderm: this is the lining of the digestive tract, and in some groups forms organs such as the liver and lungs In diploblasts, gastrulation forms 2 germ layers, ectoderm and endoderm, triploblasts gain a 3^rd^ layer called a mesoderm and at the end of embryogenesis each germ layer gives rise to a specific tissues and organs **Diploblasts in the hydra** - The blastospore becomes the open end of the gastrovascular cavity **Triploblasts such as planaria ( protostome) :** - In protostomes the mouth forms from the blastopore **Triploblasts such as sea urchin (deuterostome):** - In deuterostomes including all vertebrates as well as some invertebrates, the moth forms opposite of the blastospore. **Radial symmetry:** When there is radial symmetry there is a single opening, where the mouth and anus ( one hole) are both located on the dorsal surface **Cnidarians and ctenophores:** There are two types of cnidarians: **Polyp**: sessile( doesn't move) and attached form that waits for prey such as the sea anemone **Medusa**: moves in water to catch prey ( jellyfish) **Bilateral symmetry**: - Organisms that have bilateral symmetry typically are motile and develop sensory tissues at the anterior end including concentration of nervous tissue( brain= cephalization) - **Triploblastic: three germ layers, including a mesoderm** - Produces muscles and most other organs between the dermis and digestive tracts - **Often forms coelom which is a body cavity between the dermis and digestive tract**