Name: fern life cycles and vascular tissue
Uploaded: 2026-08-26T08:20:02.772Z
Duration: 3 min 24 s
Channel: JoVE

K12 Standards

Florida Department of Education

High School

Life Science

SC.912.L.14

SC.912.L.14.7

Seedless Vascular Plants

Existem tr&#xEA;s grupos principais cobrindo a vida vegetal na Terra plantas n&#xE3;o vasculares, plantas vasculares sem sementes, e plantas com sementes. As plantas vasculares sem sementes foram as primeiras a evoluir sistemas vasculares especializados uma adapta&#xE7;&#xE3;o que os ajudou a se tornar as primeiras plantas altas na Terra. Hoje, plantas vasculares sem sementes s&#xE3;o representadas por lic&#xF3;fitas e monil&#xF3;fitas.Lic&#xF3;fitas incluem musgos, musgos de espig&#xE3;o e isoetes. Notavelmente, nenhuma das lic&#xF3;fitas s&#xE3;o musgos verdadeiros, que s&#xE3;o plantas n&#xE3;o vasculares. Monil&#xF3;fitas incluem samambaias, cavalinhas, e samambaias batedeiras e seus parentes.Como todas as plantas, plantas vasculares sem sementes exibem uma altern&#xE2;ncia de gera&#xE7;&#xF5;es em seus ciclos de vida, como mostrado aqui usando uma planta de samambaia como exemplo. Isso significa que elas passam parte de seu ciclo de vida como um gamet&#xF3;fito haploide, e a outra parte como espor&#xF3;fito diploide. Como todas as plantas, plantas vasculares sem sementes reproduzem usando esporos, ao inv&#xE9;s vez de sementes.Os esporos s&#xE3;o haploides, e est&#xE3;o dispersos por estruturas chamadas soros, agrupadas na parte inferior das folhas. Os pr&#xF3;prios soros cont&#xE9;m muitos espor&#xE2;ngios. Ao atingir a maturidade, estes espor&#xE2;ngios se abrem, dispersando os esporos haploides.Os esporos ent&#xE3;o crescem via mitose para formar o gamet&#xF3;fito haploide. No est&#xE1;gio de gamet&#xF3;fito que &#xE9; tipicamente muito pequeno e encontrado em ou apenas abaixo da superf&#xED;cie do solo gametas haploides s&#xE3;o formada por mitose. Um &#xFA;nico gamet&#xF3;fito &#xE9; bissexual e desenvolve duas estruturas diferentes o anter&#xED;dio e arqueg&#xF3;nio que produzem gametas no macho e formas femininas, respetivamente.Como as plantas n&#xE3;o vasculares, a gameta de esperma masculino &#xE9; flagelado e requer &#xE1;gua para viajar para o gameta feminino seguindo um atrativo qu&#xED;mico para encontrar o &#xF3;vulo. Porque as gametas em um &#xFA;nico gamet&#xF3;fito ser&#xE3;o geneticamente id&#xEA;nticos devido &#xE0; sua origem haploide, cruzamentos normalmente ocorrem entre gamet&#xF3;fitos diferentes. As samambaias podem prevenir qualquer autofecunda&#xE7;&#xE3;o por ter sua anter&#xED;dia e arqueg&#xF3;nio maduras em momentos diferentes Finalmente, o ovo fertilizado ir&#xE1; crescer em um novo espor&#xF3;fito diploide a partir do zigoto diploide do gamet&#xF3;fito, completando o ciclo de vida.Como plantas com sementes, plantas vasculares sem sementes tem ciclos de vida dominado por espor&#xF3;fitos. No entanto, ao contr&#xE1;rio de qualquer uma das outras linhagens de plantas importantes, seus gamet&#xF3;fitos menores podem viver de forma independente o que significa que eles n&#xE3;o fornecem alimento para o espor&#xF3;fito, ou exigem isso do espor&#xF3;fito. Indiscutivelmente a caracter&#xED;stica principal de plantas vasculares sem sementes &#xE9; a rede especializada de tecido vascular, semelhante &#xE0; das plantas com sementes.Esta adapta&#xE7;&#xE3;o permitiu-lhes transportar &#xE1;gua, nutrientes, e outros materiais org&#xE2;nicos, e atingir tamanhos maiores que as distingue de seus parentes n&#xE3;o vasculares.

Jones, Victor A.s. e Liam Dolan. 2012. "A evolução dos pêlos radiculares e rizóides." Anais de Botânica 110 (2): 205–12. [<a href="https://doi.org/10.1093/aob/mcs136" target="_blank">Fonte</a>]

Pittermann, Jarmila, Craig Brodersen e James E. Watkins. 2013. "A resiliência fisiológica de esporófitos e gametófitos de samambaia: avanços nas relações hídricas oferecem novos insights sobre uma linhagem antiga." Fronteiras na ciência das plantas 4. [<a href="https://doi.org/10.3389/fpls.2013.00285" target="_blank">Fonte</a>]

Sigel, Erin M., Eric Schuettpelz, Kathleen M. Pryer e Joshua P. Der. 2018. "Padrões sobrepostos de expressão gênica entre as fases gametófito e esporófito na samambaia Polypodium amorphum (Polypodiales)." Fronteiras em Ciência das Plantas 9 (setembro). [<a href="https://doi.org/10.3389/fpls.2018.01450" target="_blank">Fonte</a>]

plantas vasculares sem sementes

Plantas Vasculares Sem Sementes Foram as Primeiras Plantas Altas na Terra
 
 Hoje, as plantas vasculares sem sementes s&#xE3;o representadas por monil&#xF3;fitas e lic&#xF3;fitas. Samambaias&#x2014;as plantas vasculares sem sementes mais comuns&#x2014;s&#xE3;o as monil&#xF3;fitas. Psilotum (e os seus parentes) e cavalinhas tamb&#xE9;m s&#xE3;o monil&#xF3;fitas. As lic&#xF3;fitas incluem os musgos Lycopsida, Selaginella e Isoetes&#x2014;nenhum dos quais verdadeiros musgos.
 
 Ao contr&#xE1;rio das plantas n&#xE3;o vasculares, as plantas vasculares&#x2014;incluindo plantas vasculares sem sementes&#x2014;t&#xEA;m uma extensa rede de tecido vascular composta por xilema e floema. A maioria das plantas vasculares sem sementes tamb&#xE9;m tem ra&#xED;zes e folhas verdadeiras. Al&#xE9;m disso, os ciclos de vida das plantas vasculares sem sementes s&#xE3;o dominados por esporos dipl&#xF3;ides produtores de esporos, em vez de gamet&#xF3;fitos.
 
 No entanto, como as plantas n&#xE3;o vasculares, as plantas vasculares sem sementes reproduzem-se com esporos em vez de sementes. Plantas vasculares sem sementes tamb&#xE9;m s&#xE3;o tipicamente mais bem sucedidas reprodutivamente em ambientes h&#xFA;midos porque o seu esperma requer uma pel&#xED;cula de &#xE1;gua para chegar aos &#xF3;vulos.
 
 O Ciclo de Vida das Plantas Vasculares Sem Sementes
 
 Como os animais, as plantas vasculares sem sementes (e outras plantas) alternam entre a meiose e a fertiliza&#xE7;&#xE3;o durante a reprodu&#xE7;&#xE3;o. A meiose &#xE9; um processo de divis&#xE3;o celular que produz c&#xE9;lulas hapl&#xF3;ides&#x2014;que cont&#xEA;m um conjunto completo de cromossomas&#x2014;a partir de uma c&#xE9;lula dipl&#xF3;ide&#x2014;que cont&#xE9;m dois conjuntos completos de cromossomas. A fertiliza&#xE7;&#xE3;o, pelo contr&#xE1;rio, produz uma c&#xE9;lula dipl&#xF3;ide chamada zigoto atrav&#xE9;s da fus&#xE3;o de c&#xE9;lulas hapl&#xF3;ides chamadas g&#xE2;metas&#x2014;c&#xE9;lulas de esperma e &#xF3;vulos.
 
 Na maioria dos animais, apenas o est&#xE1;gio dipl&#xF3;ide &#xE9; multicelular, e os g&#xE2;metas s&#xE3;o as &#xFA;nicas c&#xE9;lulas hapl&#xF3;ides. As plantas, no entanto, alternam entre est&#xE1;gios hapl&#xF3;ides e dipl&#xF3;ides que s&#xE3;o multicelulares; isso &#xE9; chamado de altern&#xE2;ncia de gera&#xE7;&#xF5;es. A altern&#xE2;ncia de gera&#xE7;&#xF5;es &#xE9; uma caracter&#xED;stica de todas as plantas sexualmente reprodutoras, mas o tamanho e a proemin&#xEA;ncia relativos dos est&#xE1;gios hapl&#xF3;ide e dipl&#xF3;ide diferem entre as plantas.
 
 Em plantas vasculares sem sementes (assim como em plantas com sementes), o est&#xE1;gio dipl&#xF3;ide do ciclo de vida&#x2014;o espor&#xF3;fito&#x2014;&#xE9; dominante. Por exemplo, o que a maioria das pessoas reconhece como samambaia &#xE9; o grande e independente espor&#xF3;fito de samambaia. Os espor&#xF3;fitos produzem c&#xE9;lulas hapl&#xF3;ides chamadas esporos atrav&#xE9;s da meiose.
 
 Um esporo pode germinar e se desenvolver em um gamet&#xF3;fito&#x2014;a fase hapl&#xF3;ide do ciclo de vida&#x2014;atrav&#xE9;s da mitose. Gamet&#xF3;fitos produzem &#xF3;vulos e esperma atrav&#xE9;s da mitose (ao contr&#xE1;rio dos animais, que produzem g&#xE2;metas atrav&#xE9;s da meiose). A maioria das plantas vasculares sem sementes produz um tipo de esporo que d&#xE1; origem a um gamet&#xF3;fito bissexual. Os gamet&#xF3;fitos s&#xE3;o menores e menos estruturalmente complexos que os espor&#xF3;fitos, mas podem realizar fotoss&#xED;ntese e n&#xE3;o dependem do espor&#xF3;fito para nutri&#xE7;&#xE3;o ou prote&#xE7;&#xE3;o.
 
 Os &#xF3;vulos e c&#xE9;lulas de esperma fundem-se atrav&#xE9;s da fertiliza&#xE7;&#xE3;o, formando um zigoto dipl&#xF3;ide. O zigoto divide-se atrav&#xE9;s da mitose para gerar o familiar e frondoso espor&#xF3;fito da samambaia&#x2014;continuando o ciclo.

Plantas Vasculares Sem Sementes

Seedless Vascular Plants Were the First Tall Plants on Earth

Today, seedless vascular plants are represented by monilophytes and lycophytes. ...

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Education

JoVE Core

Biology

Biologia

Plant Biology

Biologia Vegetal

Plant Structure, Growth and Function

Estrutura, Crescimento e Nutrição das Plantas

KEY TERMS AND CONCEPTS

TERMOS-CHAVE E CONCEITOS

fern life cycles and vascular tissue

Seedless vascular plants include ferns, horsetails, whisk ferns, and lycophytes. Ferns are the most common example. Whisk ferns and their relatives, along with horsetails, are monilophytes. Lycophytes include club mosses, spikemosses, and quillworts, and none of these are true mosses.

Seedless vascular plants differ from nonvascular plants because they have vascular tissue. This tissue includes xylem and phloem, which move water and nutrients through the plant. Most seedless vascular plants also have true roots and leaves. These features helped them become the first tall plants on Earth.

Their life cycle is dominated by the diploid sporophyte, not the gametophyte. The sporophyte is the familiar fern plant that people usually notice. Seedless vascular plants still reproduce with spores, not seeds. They also do better in moist places because sperm need a thin film of water to reach the eggs.

Like animals and other plants, these plants alternate between meiosis and fertilization. Meiosis makes haploid cells, which have one set of chromosomes, from a diploid cell, which has two sets. Fertilization joins haploid gametes, such as sperm and eggs, to form a diploid zygote. In plants, both the haploid and diploid stages can be multicellular, which is called alternation of generations.

In seedless vascular plants, the diploid stage is the larger and more noticeable one. The sporophyte makes haploid spores by meiosis. A spore can grow into a gametophyte by mitosis. The gametophyte is smaller and less complex, but it can still photosynthesize and does not depend on the sporophyte for food or protection.

Most seedless vascular plants make one kind of spore. That spore develops into a bisexual gametophyte, which produces both egg and sperm cells by mitosis. When fertilization happens, a diploid zygote forms. The zygote then divides by mitosis and grows into the familiar fronded fern sporophyte, continuing the cycle.

Fern Life Cycles and Vascular Tissue

introduction to plant diversity

Plant Adaptations for Life on Land

Plant adaptations for life on land explain how Kingdom Plantae moved from water to land about 410 million years ago. This shift happened when green algae began colonizing a new environment that had not been widely occupied. Land offered more light and carbon dioxide for growth, but it also created major challenges for early plants. One key adaptation was the cuticle, a waxy outer layer that helps prevent water loss. It traps moisture inside the plant. But it also limited direct gas exchange...

non-vascular seedless plants

Nonvascular Plants and Their Life Cycle

Nonvascular plants include some of the earliest plants on Earth. Today, this group includes liverworts, mosses, and hornworts. These plants are also called bryophytes. They have no true roots, leaves, or stems because they lack extensive vascular tissue. Bryophytes reproduce with spores instead of seeds. Their life cycle is dominated by the haploid gametophyte stage, which produces eggs and sperm. The sporophyte stage makes haploid spores that can grow by mitosis into new gametophytes. In many...

seedless vascular plants

Seedless vascular plants include ferns, horsetails, whisk ferns, and lycophytes. Ferns are the most common example. Whisk ferns and their relatives, along with horsetails, are monilophytes. Lycophytes include club mosses, spikemosses, and quillworts, and none of these are true mosses. Seedless vascular plants differ from nonvascular plants because they have vascular tissue. This tissue includes xylem and phloem, which move water and nutrients through the plant. Most seedless vascular plants...

introduction to seed plants

Seed Plants: Cones, Flowers, and Fruits

Seed plants are land plants that make seeds, use pollen, and have reduced gametophytes. This group includes gymnosperms and angiosperms. Gymnosperms include cycads, Ginkgo biloba, gnetophytes, and conifers. Gymnosperms usually form cones. Pollen cones contain the male gametophytes. Ovulate cones contain the female gametophytes and produce exposed seeds after fertilization. Angiosperms are the most diverse and widespread land plants. They form flowers and fruit, and both structures support...

basic plant anatomy: roots, stems, and leaves

basic-plant-anatomy-roots-stems-and-leaves

Plant Organs and Their Specialized Roles

Plants are built from roots, stems, and leaves, but each organ can change to fit a plant’s environment. These structures may look very different from one species to another. They still carry out the main jobs needed for growth and survival. Roots are usually underground, but that is not always true. Aerial roots grow aboveground. Epiphytic plants, such as orchids, can live without ever touching soil. In strangler figs and banyans, aerial roots begin aboveground, grow downward, and later reach...

plant cells and tissues

Plant Growth and Support Tissues

Plant growth and support tissues help plants grow, protect themselves, and move materials through the body. Plant tissues are groups of similar cells that do related jobs. These tissues combine to form organs such as flowers, fruit, stems, and leaves. Two major kinds of plant tissue are meristematic tissue and permanent tissue. Meristematic tissue is the main growth tissue in plants. It can keep dividing and renewing itself, and every plant cell begins in a meristem. Meristematic tissue is...

meristems and plant growth

Plant Growth from Root and Shoot Tips

Plants grow throughout their lives, and that pattern is called indeterminate growth. This trait sets plants apart from most animals. Some plant parts stop growing, such as leaves and flowers, but roots and stems can keep growing for a long time. Meristems make this ongoing growth possible. A meristem is a plant tissue that contains undifferentiated cells called meristematic cells. When these cells divide, some daughter cells stay in the meristem. That keeps a supply of cells that can keep...

primary and secondary growth in roots and shoots

primary-and-secondary-growth-in-roots-and-shoots

Root and Shoot Growth: Length vs. Width

Root and shoot growth in vascular plants happens in two main ways: primary growth and secondary growth. Primary growth makes roots and shoots longer. Secondary growth makes them thicker. Many woody plants show both kinds of growth, and the two can happen at the same time. Primary growth happens in newer parts of the plant. Secondary growth happens in regions that have already finished primary growth. In roots and shoots, the process starts in apical meristems, which are areas of actively...

morphogenesis

Plant Flowering and Organ Identity

Plant flowering and organ identity shape a plant’s form and structure. These changes depend on growth and cell differentiation, which work together during plant morphogenesis. Precursor cells become specialized cell types, and those cells are organized into tissues and organ systems that support the whole plant. Plant growth and cell differentiation are controlled by hormones. Plant hormones regulate gene expression, often in response to environmental stimuli. Temperature and day length are...

light acquisition

How Plants Maximize Sunlight Capture

Plants need light energy to make glucose, so leaf shape and plant structure help determine how well they capture sunlight. Many modern plants have evolved leaves that are specialized for light capture. Leaf size can vary from just a few millimeters wide to tens of meters wide, depending on the environment. Competition for sunlight has pushed evolution toward larger leaves and taller plants. These changes help plants avoid being shaded by nearby competitors. They also depend on root systems...

water and mineral acquisition

How Roots Absorb Water and Minerals

Roots absorb water and minerals from the soil using specialized tissues. Their branching patterns help them reach more soil, and root hairs on the outer cells increase surface area for contact with the ground. Water enters roots passively because the water concentration in the soil is higher than in root tissue. Minerals move in a different way. They are taken up actively by root cells, which requires energy and transport proteins. Soil particles carry a negative charge, so positive ions...

short-distance transport of resources

Plant Cell Membranes and Water Balance

Plant cell membranes control how water, ions, and other solutes move over short distances. This transport can happen across just 2 to 3 cells, and it begins at the plasma membrane. Small uncharged molecules, such as oxygen, carbon dioxide, and water, can diffuse through the membrane on their own. Ions and larger molecules need transport proteins because of their charge or size. Membrane transport also happens inside plant cells. The central vacuole stores resources and helps manage the cell’s...

xylem and transpiration-driven transport of resources

xylem-and-transpiration-driven-transport-of-resources

How Xylem Moves Water in Plants

Xylem moves water and dissolved minerals from the roots to the rest of the plant. The cells that carry xylem sap are dead when mature, so the flow is passive. Xylem transport depends on special tracheary elements, which connect directly with the extracellular space in the apoplast. There are two main tracheary elements: tracheids and vessel elements. Tracheids are long cells with lignified walls and small pits. These pits let xylem sap move from one cell to the next where the walls overlap.

regulation of transpiration by stomata

How Guard Cells Open Plant Stomata

How guard cells open and close plant stomata controls gas exchange in leaves. A stoma is a tiny opening in the leaf epidermis. The word comes from the Greek word for “mouth.” These openings let plants take in carbon dioxide for photosynthesis and release oxygen into the air. Each stoma is surrounded by two guard cells. When these cells take up water, they create an opening. Ion transport controls how much water stays in the guard cells. A trigger causes pumps to move hydrogen ions out of the...

adaptations that reduce water loss

Plant Features That Limit Water Loss

Plant features that limit water loss help plants survive in dry or hot environments. Water is needed for photosynthesis and other cell processes, so plants have evolved several ways to slow evaporation from their leaves. One major barrier is the cuticle, a waxy layer on the leaf epidermis. The epidermis is the outer cell layer, and it makes cutin and other plant waxes that form this hydrophobic coating. The cuticle helps stop water from escaping and also keeps out unwanted solutes. Its...

phloem and sugar transport

How Phloem Moves Sugars in Plants

Phloem moves sugars and other materials through plants. In angiosperms, sugar production is mostly limited to photosynthetic cells in the leaves. These leaves act as sugar sources because they make more sugar than they use. Roots, shoots, flowers, and fruits are usually sugar sinks because they need more sugar than they can make. This movement is called translocation. It carries sugar, hormones, amino acids, and some signaling molecules from source tissues to sink tissues. The transport...

the soil ecosystem

Soil Layers and How Soil Forms

Soil supplies plants with water and inorganic minerals. It is the natural medium for land plants, and its quality depends on both chemical makeup and living organisms in the soil. Healthy soil contains enough air, water, minerals, and organic matter to support plant growth. Soil is made of three major components. Inorganic mineral matter makes up about 40 to 45 percent of soil volume. Organic matter, also called humus, makes up about 5 percent. Water and air fill about 50 percent of the volume.

key elements for plant nutrition

Plant Nutrients: Macro and Micro Needs

Plants need both organic and inorganic nutrients to survive, grow, reproduce, and keep normal cell function. Researchers use hydroponics to study these essential nutrients. In hydroponic culture, plants grow without soil in water-based nutrient solutions. At least 17 nutrients are known to be essential for plants. Plants get these elements from the atmosphere, the soil around their roots, and water. Nine of them are macronutrients, which plants need in larger amounts. These macronutrients are...

the roles of bacteria and fungi in plant nutrition

the-roles-of-bacteria-and-fungi-in-plant-nutrition

How Soil Microbes Help Plants Get Nutrients

Soil microbes help plants get nutrients, water, and protection. Plants can make their own food by photosynthesis, but they still depend on organisms in the soil to get the nutrients they need to work properly. Bacteria and fungi form symbiotic relationships with plants, which helps both partners survive in many environments. The bacteria living in and around plant roots are called the rhizosphere. This community is very diverse. Some bacteria can cause disease, but most help plant health. In...

epiphytes, parasites, and carnivores

Plant Nutritional Adaptations in Nature

Plant nutritional adaptations help some species survive by using fungi, bacteria, or other plants and animals. Many plants also rely on mutualistic partners in the soil. Root-colonizing fungi, such as mycorrhizae, increase root surface area and improve nutrient absorption. Nitrogen-fixing bacteria, such as rhizobia, convert atmospheric nitrogen (N2) into ammonia (NH3), which plants can use to build essential molecules like chlorophyll. These relationships benefit both sides. The plant gets...

the apoplast and symplast

Plant Water Transport Pathways

Plant water transport pathways help roots absorb water and dissolved minerals from the soil. These pathways move materials through plant tissues that support growth and nutrient uptake. The main tissue regions involved are the apoplast and the symplast. The apoplast includes everything outside the plasma membrane of living cells. It contains cell walls, extracellular spaces, xylem, phloem, and tracheids. The symplast is the cytosol of all living plant cells, along with the plasmodesmata that...

key terms and concepts

Learn how seedless vascular plants use xylem, phloem, spores, and alternation of generations, with ferns as the best-known example.

Fern Life Cycles and Vascular Tissue | JoVE K12

JoVE Core series brings biology to life through over 300 concise and easy-to-understand animated video lessons that explain key concepts in biology, plus more than 150 scientist-in-action videos that show actual research experiments conducted in today’s laboratories.

biology

A coleção JoVE Core dá vida à biologia através de mais de 300 vídeos de animação concisos e fáceis de entender que explicam conceitos-chave de biologia, além de mais de 150 vídeos de Cientistas em ação que mostram experimentos reais em pesquisa realizados nos laboratórios atualmente.

SC.912.L.14.8

SC.912.L.14.10

SC.912.L.14.53.

Georgia Standards of Excellence

9-12

Botany

SBO1.

change-in-plant-straucture-through-geological-time

Change in plant straucture through geological time

What are Cells?

Cells are the smallest and basic units of life, whether it is a single cell that forms the entire organism, e.g., in a bacterium or trillions of them, ...

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https://cloudfront.jove.com/files/media/science-education/science-education-thumbs/10647.jpg

Animal and Plant Cell Structure

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Eukaryotic Evolution

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The cell is chemically composed of water, organic molecules and inorganic ions.
Water
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Describe the scientific theory of cells (cell theory) and relate the history of its discovery to the process of science.

SC.912.L.14.1

Cell Size

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Eukaryotic Compartmentalization

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Prokaryotic Cells

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Cytoplasm

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The Nucleus

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Endoplasmic Reticulum

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Ribosomes

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Golgi Apparatus

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Microtubules

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Plant Cell Wall

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Plasmodesmata

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What are Membranes?

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Membrane Fluidity

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Fluid Mosaic Model

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Osmosis

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Tonicity in Animals

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Primary Active Transport

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Secondary Active Transport

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Receptor-mediated Endocytosis

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Pinocytosis

Cells use energy-requiring bulk transport mechanisms to transfer large particles, or large amounts of small particles, into or out of the cell. The cells ...

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While endocytosis takes particles ...

Relate structure to function for the components of plant and animal cells. Explain the role of cell membranes as a highly selective barrier (passive and active transport).

SC.912.L.14.2

Cell Structure

Background
Cells represent the most basic biological units of all organisms, whether it be simple, single-celled organisms like bacteria, or large, ...

Compare and contrast the general structures of plant and animal cells. Compare and contrast the general structures of prokaryotic and eukaryotic cells.

SC.912.L.14.3

Overview of Microscopy Techniques

The early pioneers of microscopy opened a window into the invisible world of microorganisms. In 1830, Joseph Jackson Lister created an essentially modern ...

Introduction to Light Microscopy

The light microscope is an instrument used by researchers in many different fields to magnify specimens to as much as a thousand times their original ...

Overview of Electron Microscopy

The wavelengths of visible light ultimately limit the maximum theoretical resolution of images created by light microscopes. Most light microscopes can ...

phase-contrast-and-differential-interference-contrast-microscopy

Phase Contrast and Differential Interference Contrast Microscopy

Phase-Contrast Microscopes
In-phase-contrast microscopes, interference between light directly passing through a cell and light refracted by cellular ...

Confocal Fluorescence Microscopy

Confocal microscopy is an advanced microscopic technique. The prime advantage of the confocal microscope over other microscopy techniques is its ability ...

Compare and contrast structure and function of various types of microscopes.

SC.912.L.14.4

A. Cells have characteristic structures and functions that make them distinctive.

B. Processes in a cell can be classified broadly as growth, maintenance, reproduction, and homeostasis.

C. Life can be organized in a functional and structural hierarchy ranging from cells to the biosphere.

D. Most multicellular organisms are composed of organ systems whose structures reflect their particular function.

Fern Life Cycles and Vascular Tissue

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