fundamentals of biology shipley’s marine biology

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  • Fundamentals of BiologyShipleys Marine Biology

  • Just like water is a molecule, there are other molecules important to life.Four organic (contain carbon, hydrogen and oxygen) molecules make up living organisms:CarbohydratesProteinsLipidsNucleic acidsThe Essential Building Blocks of Life

  • Carbohydrates:Made of carbon, hydrogen and oxygen at a 1:2:1 ratio (example: glucose is C6h12O6).Most carbohydrates are used for energy for organisms.Some are used to store energy to be used later (like starch found in plants and some algae.Some are used in structure such as chitin found in the shells of some animals (like crabs, lobsters and shrimp) or cellulose found in plants.

    The Essential Building Blocks of Life

  • Proteins:Composed of smaller units known as amino acidsEnzymes are specialized proteins necessary for chemical reactions in an organismSome proteins are hormones that act as chemical messengers within an organismOthers can be used in structure, immunity, internal transport among other duties

    The Essential Building Blocks of Life

  • The Essential Building Blocks of LifeLipids:Lipids are mainly hydrophobic (do not mix with water remember the saying that oil and water dont mix).Due to this principle, many marine organisms use a coating of lipid to cover fur or feathers which provides an insulating layer.Some also have a layer of lipid (fat) underneath the skin for insulation.Many lipids are used for energy storage within an organism.They can also be used for internal structure or as hormones.

  • Nucleic Acids:Made of smaller units called nucleotides.DNA and RNA are nucleic acids.DNA is the molecule of heredity; it provides the instructions for making every part of an organism.RNA helps with this duty in multiple ways.The Essential Building Blocks of Life

  • Energy and LifeMany organisms use sunlight to drive the process of photosynthesis.In photosynthesis, plants, algae and other autotrophs use pigments to capture the energy in sunlight.This energy is used to build carbohydrates.The source of carbon for building carbohydrates is carbon dioxide; oxygen is released as a by-product

  • Whether an organism makes their own carbohydrates (autotrophs) or gets carbohydrates by eating other organisms (heterotrophs), they still must break down the carbohydrates within their cells for energy.This process is known as cellular respiration.Respiration consumes oxygen and produces carbon dioxide and water as by-products.Energy and Life

  • Some of the carbohydrates made by photosynthetic organisms are converted into other types of molecules such as:ProteinsLipidsNucleic acidsEnergy and Life

  • When these autotrophs make more energy than they can use, the excess is called primary productionOrganisms responsible for this primary production are called primary producersMarine organisms are a major source of worldwide primary productionEnergy and Life

  • Marine organisms require nutrients to convert carbohydrates to other types of moleculesThese nutrients can include minerals, vitamins and even raw elementsEx: silica is required to make the shell of some organismsEnergy and Life

  • All living organisms can be divided into two basic groups based on cellular composition:

    ProkaryoticEukaryotic

    Types of Organisms

  • Prokaryotic Organisms:Lack a nucleusPosses ribosomesContain a circular ring of DNASome may also have plasmids, extra pieces of DNACell wall is normally presentMay have a flagellumUnicellularTypes of Organisms

  • Eukaryotic OrganismsPossess DNA enclosed inside a nucleusPosses many specialized organelles (look at organelles in Fig. 4.8)Eukaryotic organisms can be unicellular or multicellular

    Types of Organisms

  • Mitochondria- site of cellular respirationGolgi complex and endoplasmic reticulum- manufacture, package and transport cellular products such as proteins (Vesicles transport things from one place to another.)Ribosomes- manufacture proteinsChloroplasts- site of photosynthesisVacuole- storage of water and nutrientsCentrioles- assist in movement of chromosomes during cellular reproductionExample Organelles in Eukaryotic Organisms

  • Atom fundamental unit of all matterMolecule two or more atoms chemically joined togetherLevels of Organization in Living Organisms

  • Organelle specialized features of cells

    Cell basic unit of lifeLevels of Organization in Living Organisms

  • Tissue group of cells functioning as a unitOrgan many tissues arranged into a structure with a specific purpose in an organismLevels of Organization in Living Organisms

  • Organ system group of organs that work together

    Whole organism (individual)Levels of Organization in Living Organisms

  • Population group of organisms of the same species occurring in same habitatLevels of Organization in Living Organisms

  • Community all species that exist in a particular habitat (ex: all the organisms on a coral reef)Ecosystem combination of the community and the physical environmentLevels of Organization in Living Organisms

  • Solutes (substances dissolved in water) will move from areas where they are more concentrated to an area where they are less concentratedThis movement is called diffusionMovement of water from an area where it is more concentrated to an area where it is less concentrated through a semipermeable membrane is called osmosis.

    Diffusion and Osmosis

  • Since marine organisms live in a very solute-rich environment, they have a tendency to gain solutes and lose waterThis can result in the death of cells if the water loss/solute gain is significantThese organisms must find ways to deal with this diffusion and osmosis

    Diffusion and Osmosis

  • Osmoconformers-Do not attempt to control solute/water balanceTheir internal concentration varies as the salinity in the water around them changesMost can only tolerate a very narrow range of salinityRegulation of Solute/Water Balance

  • OsmoregulatorsThese organisms control their internal concentrationsCan generally tolerate a wider range of salinities than osmoconformersThis can be done in a variety of ways such as secreting very little urine or using specialized glands to secrete salts as examples Regulation of Solute/Water Balance

  • Go to www.cellsalive.com/In the left-hand column labeled Interactive, click PuzzlesOn the Cells Alive! Puzzle Page, complete both Animal Cell and Plant Cell Jigsaw puzzles.Upon completing the puzzle, right click the mouse, and click PRINT.On the same page, under Word Puzzles, complete Cell Structure #1 and Cell Structure #2.Again, upon completing each puzzle, print finished puzzle.Homework Assignment

  • EctothermsGenerate body heat metabolically, but cannot maintain constant internal body temperatureExamples: snakes, lizards, frogs, insectsPoikilothermsBody temperature mimics the surrounding environment. They do not use their metabolisms to heat or cool themselves.Many ectotherms are poikilotherms.Examples: fish, reptilesTemperature Control

  • EndothermsGenerate body heat metabolically and body temperature does not match the temperature of the surrounding environmentAll birds and mammals

    HomeothermsThese organisms retain metabolic heat and can control metabolism to maintain a constant internal temperatureHomeotherms are endotherms

    Temperature Control

  • Asexual reproductionDoes not involve mating of two individualsYoung are produce by a single parent organismThe young produced are genetically identical to the parent

    Modes of Reproduction

  • Examples of Asexual ReproductionFission the splitting of one organism into two smaller organisms of equal sizeBudding the organism develops buds (small clones) that eventually break off and become another organismVegetative reproduction a plant reproduces new individuals by sending an underground stem (rhizome) sideways from which new plants will sprout

    Modes of Reproduction

  • Sexual reproductionNormally involves two individualsParent individuals produce gametes (eggs or sperm) that unite to produce a new, genetically unique individualOvaries are the organs that produce eggsTestes are the organs that produce spermModes of Reproduction

  • Many marine organisms release their eggs and sperm directly into the water, this is known as broadcast spawning.For broadcast spawning to be effective, millions of gametes must be released into the water at roughly the same time to ensure fertilization will occurMany broadcast spawning species time the release of their eggs to tides, moon phase, water temperature, etc. to ensure successModes of Reproduction

  • Other marine organisms rely on internal fertilization, where a copulatory organ is used to insert sperm directly into the females reproductive tractThis method requires contact between parent individuals, but less gametes are required for successModes of Reproduction

  • Hermaphrodites individuals that have male and female reproductive tissues either simultaneously or at different phases during the life. Examples:Protandry- an individual spends the first portion of the life as a functional male then becomes a female later in life after some cue initiates the changeProtogyny- an individual spends the first portion of the life as a functional female then becomes a male later in life after some cue initiates the change

    Modes of Reproduction

  • Evolution is defined as a change in the genetic make-up of a population over timeIn the wild, any genetically derived traits (such as faster swimming or above-average intelligence) can give one individual survival advantage over others in his/her population