...* Chapter 25 * Evolution has to work with existing forms * Heterochrony Evolutionary change in rate or timing of developmental events * Padomorphosis Mature state of an organism retains juvenile characteristics Spatial Patterns Rearranges structural features through changes in gene expression or gene duplications. Homeotic genes control 3-D patterns of multicellular organisms Hox gene family: HoxC6 expressed (no limbs), HoxC6 not expressed (limbs can form) Jellyfish to humans Exaptation Traits evolved in one context are used for an entirely different function Feathers first thought to be used as insulation. Feathers are an exaptation- evolved in context of insulation, now used for different function (flight) Adaptive Radiation: a single lineage (common ancestor) undergoes rapid speciation and ecological diversification to form multiple new species. Can occur when: Key Adaptation Adaptations that allow a lineage to exploit new habitats( or resources) and diversify rapidly If key adaptations evolve convergently in different groups: compare diversity of group with key adaptation to diversity of sister group lacking key adaptation (paired t-test) After mass extinction event (leaves many vacant niches for organism to diversify and fill Colonization of a new habitat/location Rapid diversification of “picture-winged” Drosophila on Hawaiian Islands Hypothesis of Chemical Evolution Abiotic synthesis of small organic molecules Observed...
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...Before plants, the earth was a rather dull place. It is predicted that the plants changed land quite a lot. For example, before plants, rivers were thought to be broad, shallow, and laid down in wide, flat sheets. Then plants growing and roots spreading in these areas helped to transform the land into areas of mud with rivers in long continuous, and narrow channels. Bacteria started forming before plants, and it is believed that this bacteria is what began to pump oxygen into the atmosphere. About 2 billion years after bacteria started developing, was the rise of bryophytes descending from the green algae. This is believed to have happened about 409-354 million years ago. They lack lignified vascular tissue and therefore cannot grow to be very tall. Therefore it is believed that the bryophytes were very small and low to the ground. They also needed water to survive and were found most commonly in wet habitats. With the emergence of these basic plants, they were then able to provide more of a food source for early amphibians which evolved shortly after. Amphibians and insects evolved close in the same time-frame, along with early vascular land plants. The first vascular plants fossils appeared about 425 million years ago in rocks from middle Silurian. These plants had a few features that made them able to adapt well to life on land. First, the vascular systems abled them to transport water, nutrients and sugars much more efficiently. Also, they were able to synthesize...
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...Valdaise Chedjou, 401072 GSB102f11, VME9e ch 30, 31 Page 321-329 Survey of Plant Kingdom Gymnosperms of Phyla Cycadophyta, Ginkgophyta, Coniferophyta, and Gnetophyta Gymnosperms are plants with exposed seeds borne on scalelike structures called (strobili). Gymnosperms are heterosporous. They produce two types of spores: Microspores occur in male cones and form male gametophytes. Megaspores occur in female cones and form female gametophytes. Gametaphytes of gymnosperms are microscopic and completely dependent on the large, free-living sporophyte. Pollination is the transfer of pollen from male cones to female cones, which house the eggs. Pollen is carried from the male cones to the female cones by the wind. Sperm of cycadophyta are flagellated. Phylum Ginkgophyta consists of one species, Ginko biloba, a large dioecious tree that does not bear cones. Phylum Coniferophyta are the large group of cone- bearing plant that includes the 5000 years old bristlecone pine, earth’s oldest living individual organisms. The cones they bear are reproductive structures of the sporophyte generation. Sporophylls bear spores in conifers; sporophylls of male cone are called microsporophylls. Microsporangium are the cells on the surface of each mocrosporophyll that produces spores. Sporophylls of female cones are megasporophylls; each bear two spore- producing megasporangia on its upper surface. Pollination and seed formation in pine Pollination is the transfer of pollen...
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...Name __Joel Mason____ Sec. ______ BIO 182L – Angiosperms Lab Report 1. Q2, p.335 (1 pt). a. How many carpels (locules) are apparent? -One carpel is apparent. b. How many ovules are developing in each locule? -There is one ovule in each locule. 2. Q4, p. 339 (1 pt). a. OMIT b. Can you see vegetative and generative nuclei in the pollen tubes? -Yes. 3. Q5, p. 342 (1 pt). a. Why is the endosperm being digested? -It is providing nourishment for the zygote or baby plant. b. Is Capsella a monocot or dicot? How can you tell? -Capsella is a dicot. You can tell this because the embryo has two cotyledons (seeds). 4. Q7, p. 343 (1 pt). a. OMIT b. OMIT 5. Q8, p. 344 and Q9, p. 344 (1 pt.) a. Does the pod appear to be a single carpel with one cavity containing seeds? -Yes. b. Is the micropyle near the attachment of the seed to the pod? -Yes. Q9 a. Before today would you have referred to the uncracked sunflower achene as a fruit? Why or why not? -No I wouldn’t have referred to an uncracked sunflower achene as a fruit because it never registered as having seeds to me before. I also never really thought about it but now that I do it’s very obvious that it is. b. Is sunflower a monocot or dicot? -A sunflower is a dicot. 6. Q11 a, p. 346 (1 pt). a. How many carpels are fused to form an apple? -Five carpels fuse to form an apple. 7. Q1, p.346 (1 pt). What is meant by “double fertilization”...
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...Survey of the Plant Kingdom Gymnosperms of Phyla Cycadophyta, Ginkgophyta, Coniferophyta, and Gnetophyta Exercise 30 Françoise Jessica Lisa Question 1 a). The presence of the flagellated sperm in cycads is surprising, because they do not have true flowers and their seeds are borne naked.. In other gymnosperms and angiosperms, the sperm is transported directly to the female ovule by a sperm tube, and does not have the flagellated sperm. b). The possession of flagellated sperm has a primitive characteristic in the plant kingdom, because it has characteristics of early ages in the history of mankind. Question 2 a). Dioecious means having the male and female reproductive organs are borne on separate individual plants. Question 3 a). The needles are arranged vertically pointed up, outwards, and are stuck close to one another; attached in clusters. b). In a bundle, there are two leaves in a bundle. c). Pine leaves have needles, instead of flat leaves, like the broad-leaved trees. The needles help to survive winter’s hardship. For example, the needles cut evaporation so trees can save water, which is very useful during the winter season. Broad leaves trees, produce new leaves every spring. Photosynthesis occurs rapid in broad- leaved trees, unlike the pine leaves. d). Pines are called evergreens because the tree does not shed its leaves during the fall, they stay green all year around. e). Pine roots and fir are some plants that we’ve studied in the lab...
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...What is the most derived and successful group of plants? 3. What group of gymnosperms is most closely related to angiosperms? 4. Fill in the table. Plant | Number of Cotyledons | Arrangement of Vascular Tissue | Vein Pattern | Number of Petals | Root | Monocot | | | | | | Dicot | | | | | | 5. What is the difference between xylem and phloem? 6. What kind of tissue is responsible for growth? 7. What are the 4 whorls of a flower? What is the purpose of each? a. b. c. d. 8. Explain the process of alteration of generations. 9. _____________ _____________ occurs when the pollen tube releases two ________ into the female gametophyte within the __________. One sperm ______________ the egg and the other combines with two _____________ in the central cell of the female gametophyte and initiates development of the food-storing _________________. 10. What is the purpose of fruit and nectar? 11. I am a white flower with a fruity odor that only opens at night. I have abundant, hidden nectar. How am I likely pollinated? 12. I am a bright red flower with no odor that only opens during the day. I have ample hidden nectar. How am I likely pollinated? 13. I am a brown flower that is open all day long. I have no odor or nectar. How am I likely pollinated? 14. What are the two key adaptations of angiosperms? 15. Name three reasons plants are important to humans. 16. What are...
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...Title: Seed Plants 2: Angiosperms Aim: To draw and label six diagrams related to flowering plants Introduction: Angiosperms are flowering, fruit-bearing plants or trees known for having ovules (and therefore seeds) developed within a closed ovary. Angiosperms are plants producing flowers. Thus, they are also commonly called as the flowering plants. They belong to the kingdom Plantae, subkingdom Embryophyta. They can be classified as monocotyledons and eudicotyledons. Characteristics of Angiosperms * The flowers serve as the reproductive organs for the plant.(exchanging genetic information) * They have small pollen grains that spread genetic information from flower to flower. * They have stamens- reproductive structures found in flowers that produce the pollen grains that carry the genetic information. * They have much smaller female reproductive parts, allowing them to produce seeds more quickly. * They have carpel that encloses developing seeds that may turn into fruit. * A great disadvantage is the production of endosperm. It is a material that forms after fertilisation and serves as a highly nutritional food source to the developing seed and seedling. The life cycle of Angiosperms They follow: * Seed * Germination * Sprout or seedling * Mature plant * Flowering Materials: * Flower for dissection (hibiscus flower) * Scalpel * Dissecting microscope * Prepared slide of young lily anther, c.s. * Prepared...
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...Lesson 3 essay questions Exam # 25085400 1. Directional and disruptive selection can be compared because they both favor extreme phenotypes, they adjust to their environments over time and they both cause a shift in the distribution curve. The contrast in directional selection is the distribution curve shifts one way and only focuses on one extreme phenotype. An example of directional selection would be the gradual increase in size of the modern horse. This change occurred due to the environment changing from forest conditions to grassland conditions. The contrast in disruptive selection is the distribution curve shifts both ways and focuses on two or more phenotypes versus intermediate phenotypes. An example of disruptive selection is the British snails. They live in low-vegetation areas and in forest areas. Thrushes feed on the the snails with dark shells and no bands in the vegetation areas and they feed on the snails with the light bands in the forest areas. Therefore, these snails had to adapt to their own environment. 2. Overuse and misuse of antibiotics can cause resistant bacteria to form through natural selection. When you introduce selective pressure (antibiotics) to a bacterial infection, some of the bacteria can acquire “free” DNA from its environment. Which can mimic the antibiotics genetic make up. This causes some bacteria to create a resistant gene that can be passed to the next generation. As a result the genetically resistant bacteria keeps increasing...
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...Lesson 3 Essay Questions: 1. Compare and contrast directional selection and disruptive selection and provide an example of each. Both directional and disruptive selection is a type of natural selection. Natural selection is the differential survival and/or reproduction of organisms as a function of their physical attributes. (phenotype) This results in evolution over many generations. Each mode of selection alters the mean or variance of a phenotypic trait in a population or species. These distributions can be represented in bell curves. Both selection processes can be influenced by human interaction. Directional Selection occurs when an extreme phenotype at one end of a population distribution is favored over all other phenotypes and over many generations it will lead to one distinct form. An example of directional selection is resistance to antibiotics. When an antibiotic is administered a few of the bacteria survive because they are genetically resistant. The surviving bacteria will pass on this phenotype (resistance) to the next generation. Over time the bacteria will be completely resistant to the initial antibiotic. Disruptive selection is an outcome of natural selection in which both extreme phenotypes at the end of a population distribution are favored over the average phenotype. This type of selection favors polymorphism, the occurrence of two different forms in a population of the same species. It can also lead to specification and form two or...
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...terrestrial environment about 475 million years ago- some possess water-conducting tubesWater-conducting tubes- prototypes of vascular tissues that fully developed in the next group | | 2. Seedless Vascular plants-evolved about 400 million years ago-they reproduce through spores-structures with vascular tissues eventually diversified and allowed a wider range of sizes for plants wherein the vascular tissues permit transport of water and nutrients across longer distances | | 3. Seeds-provided a natural advantage for colonizing drier lands as they protect plant embryos from harsh environment factorsCone- earliest seed plants bear naked seeds on reproductive structures -they gave rise to the group of cone-bearing plants (gymnosperms) about 200 million years ago | | 4. Flower- Bearing Plants * They emerged about 130 million years agoFlowers- complex reproductive structures that bear seeds within chambers called Ovaries. | | Additional notes: Mosses -the first group of land plants are the mosses and their allies, the liverworts and hornworts. Together, they are called the bryophytes. -they are land plants, but do not have seeds or flowers. -lack vessels, so they are restricted to smaller sizes and more moist environments than other land plants. Gametophyte generation- is the one that produces gametes, not the one that produces spores. Sporophyte generation- is a little plant that grows on or just under the soil and is rarely seen. Ferns -Ferns,...
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...flowing plants Q. Why are flowing plants considered by many botanists to be the most successful land plants? Answer to the student: The plants in which the sex organs are carried within the flowers and the seeds are enclosed in a fruit are called angiosperms. Angiosperms are commonly known as flowering plants. Many botanists considered the flowering plants are the most successful group of land plants. Flowering plant success is primarily attributed to their co-evolution with animals (Chae K, Lord EM, 2011). When spore-producing plants need on water for reproduction, while non-flowering seed plants need wind to carry pollen to a seed. There are some systems of nature it contains to success. Earliest developments that led to the flowering plants' to success were the evolution of a vascular system. The vascular system allowed them to grow larger and shade their competitors (Chae K, Lord EM, 2011). Root system with a large surface area allowed for absorption of minerals, phosphates, sulphates, fixed nitrogen, and water and this system is help to grow especially water. Root system allowed for mutualistic relationships with some fungi, and, in legumes, nitrogen-fixing bacteria. The waxy cuticle and bark slowed water loss even in direct sunlight. Pollen allowed plants to grow at a distance from each other in dry climates the sperm did not have to swim across the environment. Flowers (color, scent, nectar) attracted pollinators (Chae K, Lord EM, 2011). Seeds containing nutrients...
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...Importance of Thermoacidophiles -The importance and impact that microbial activity has on the geology, geochemistry and ecology of hydrothermal vent ecosystems is now well-recognized. Given the recent discovery that the first cultured member of the deep-sea endemic archeael lineage, DHVE2, is a thermoacidophile, growing best at pH 4.5 and unable to grow above pH 6, the investigators in this project are poised to use this organism as a model organism to explore the ecology of thermoacidophiles at deep-sea vents. Importance of Methanogenium thermophilum -In four species of methanogens able to grow with secondary alcohols as hydrogen donors the expression and properties of secondary alcohol dehydrogenase (sec-ADH) were investigated. Cells grown with 2-propanol and CO2 immediately started to oxidize secondary alcohols to ketones if transferred to new media. Importance of Methanobacterium Thermoautotrophicum -The complete 1,751,377-bp sequence of the genome of the thermophilic archaeon Methanobacterium thermoautotrophicum deltaH has been determined by a whole-genome shotgun sequencing approach. A total of 1,855 open reading frames (ORFs) have been identified that appear to encode polypeptides, 844 (46%) of which have been assigned putative functions based on their similarities to database sequences with assigned functions. Importance of Gram-positive - Gram-positive bacteria are so called because they take up the violet stain used in the Gram staining method. Gram-positive...
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...Name: Date: March 16, 2014 Instructor’s Name: Professor Tyra Hall – Pogar Assignment: SCIE207 Phase 5 Lab Report Title: Taxonomy Lab to Show Organism Relationships Instructions: You will need to fill out the data table and answer a set of questions. When your lab report is complete, post it in Submitted Assignment files. Part 1: Using the lab animation, fill in the following data tables to help you answer the questions that follow: Table 1: Samples 1–5 Phylum/Division | Sample 1: Chrysophyta | Sample 2: Annelida | Sample 3: Arthropoda | Sample 4: Amphibia | Sample 5: Aves | Common Feature | Unicellular, primary producers| Segmented body | External skeleton and segmented body | Can obtain oxygen from aquatic and terrestrial biomes | Able to fly; covered with feathers | NutritionHow does the organism break down and absorb food? | Autotrophic | Heterotrophic: Earthworms eat their way through dirt, so they are detritivores. | Heterotrophic: Some are vegetarian, some are carnivorous, and some are decomposers. | Heterotrophic: These are usually vegetarian as tadpoles and carnivores as adults. | Heterotrophic | Circulatory System (Transport)How does the organism get what it needs to cells (open, closed, diffusion only)? | Diffusion only | Closed with 5 aortic arches (hearts) | Open circulatory system with a heart pumping hemolymph | Closed with 3-chambered heart | Closed with 4-chambered heart | Respiratory SystemHow does the organism get oxygen...
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...many growing seasons to clean up a site using this method and its use must be restricted to sites with contamination only as deep as the roots of the plants being used. 42. You are exploring the beach on a tropical island and come across a strange-looking plant that washed ashore. It has been at sea for many weeks, but still has clear features. You think it may be new to science, so you want to classify it. It has the following five features: • Long leaves with narrow blades (60cmx3cm) • Parallel veins on the leaves • A taproot • A short thick stem covered in a tough waxy epidermis • One cotyledon a) Is the plant an angiosperm or a gymnosperm? Explain your answer. The plant has parallel veins on the leaves, and one cotyledon which means that it is classified as a monocot. If it was a gymnosperm, it could not be a monocot, and this means that it is an angiosperms. Its long leaves with narrow blades also makes it a monocot since plants such as grasses and corn have long, narrow leaves with parallel veins and they are classified as a monocot. b) Based on these five features, explain whether you think it came from a desert island or a tropical rainforest jungle. The fact that this plant has a stem covered in a tough waxy epidermis means that it has a lot of cutin. This means that it is protecting itself from dehydration and has a large amount of light. It needs protection from burning and drying out which is consistent with desert plants. The waxy cutin repels water, which may...
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...organism at all. Myxomycetes, or slime molds, are also not considered plants, but rather are heterotrophs that can ingest bacteria, fungal spores, and other items. The scientific study of plants, known as botany, has identified about 350,000 extant taxa of plants, defined as seed plants, bryophytes, ferns and fern allies. As of 2008, approximately 400,000 plant species have been described,[2] of which roughly ninety percent are flowering plants. Vascular plants have lignified tissue and specialized structures termed xylem and phloem, which transport water, minerals, and nutrients upward from the roots and return sugars and other photosynthetic products. Vascular plants include ferns, club mosses, flowering plants, conifers and other gymnosperms. A scientific name for this vascular group is Tracheophyta.[3] The major divisions of Plantae are: Anthocerotophyta (hornworts: nonvascular plants with one chloroplast per thallus cell) Bryophyta (mosses: nonvascular plants with wiry stems that reproduce by spores) Cycadophyta (cycads: nonflowering vascular plants with large...
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