Name: plant adaptations for life on land
Uploaded: 2026-08-26T08:19:12.622Z
Duration: 2 min 45 s
Channel: JoVE

K12 Standards

Florida Department of Education

High School

Life Science

SC.912.L.14

SC.912.L.14.7

Introduction to Plant Diversity

Antes das plantas colonizarem a terra a partir do mar, os continentes eram est&#xE9;reis. Agora milh&#xF5;es de esp&#xE9;cies de micr&#xF3;bios, plantas e animais vivem em terra, e&#xA0;foi a evolu&#xE7;&#xE3;o das plantas terrestres que tornou tudo isso poss&#xED;vel. Para entender essa transforma&#xE7;&#xE3;o surpreendente, &#xE9; primeiro necess&#xE1;rio compreender o que exatamente s&#xE3;o as plantas, e como elas evolu&#xED;ram para encontrar os desafios da vida na terra.Existem certas caracter&#xED;sticas que todas as plantas compartilham, das &#xE1;rvores mais altas at&#xE9; o menor musgo. Primeiro, todas as plantas s&#xE3;o eucariotas multicelulares. Em segundo lugar, as plantas produzem o pigmento fotossint&#xE9;tico clorofila em organelos denominados cloroplastos, permitindo-lhes produzir seus pr&#xF3;prios alimentos usando a energia do sol.Em terceiro lugar, todas as plantas t&#xEA;m c&#xE9;lulas que est&#xE3;o rodeadas por paredes feitas de celulose. Finalmente, todas as plantas possuem um ciclo de vida caracterizado pela altern&#xE2;ncia de gera&#xE7;&#xF5;es, definida como a transi&#xE7;&#xE3;o entre est&#xE1;gios multicelulares haploides e diploides ao longo do ciclo de vida. Aqui, gera&#xE7;&#xF5;es se referem a duas fases multicelulares diferentes no ciclo de vida.Uma fase &#xE9; o gamet&#xF3;fito haploide. O gamet&#xF3;fito produz g&#xE2;metas por&#xA0;mitose, que se fundem durante a fertiliza&#xE7;&#xE3;o para formar uma c&#xE9;lula diploide, que ent&#xE3;o sofre mitose para evoluir em um espor&#xF3;fito. O espor&#xF3;fito, por sua vez, produz esporos haploides por meiose, completando o ciclo dando origem para novos gamet&#xF3;fitos.Embora todas as plantas compartilhem estas caracter&#xED;sticas, h&#xE1; diferen&#xE7;as gritantes entre as diversas linhagens de plantas em como algumas destas caracter&#xED;sticas s&#xE3;o expressas. As plantas terrestres caem em tr&#xEA;s grupos principais, as plantas n&#xE3;o vasculares, as vasculares sem semente, e as plantas de semente. Cada um desses grupos cont&#xE9;m muitas milhares de esp&#xE9;cies.com a progress&#xE3;o do tempo evolucion&#xE1;rio, os tr&#xEA;s grupos evolu&#xED;ram com tra&#xE7;os diferentes que os caracterizam do tecido vascular, a evolu&#xE7;&#xE3;o dos frutos. Juntas, estas adapta&#xE7;&#xF5;es possibilitaram as plantas dominarem mais biomas terrestres.

Ziv, C., et al. (2018). "Papéis multifuncionais da cutícula da planta durante as interações planta-patógeno." Front Plant Sci 9: 1088. [<a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6068277/">Fonte</a>]

Gupta, R. e R. Deswal (2014). "As proteínas anticongelantes permitem que as plantas sobrevivam em condições de congelamento." J Biosci 39(5): 931-944. [<a href="http://www.plantphysiol.org/content/138/1/330">Fonte</a>]

introdução à diversidade vegetal

Da &#xE1;gua para a terra
O reino Plantae surgiu pela primeira vez h&#xE1; cerca de 470 milh&#xF5;es de anos, quando as algas verdes car&#xF3;fitas fizeram a transi&#xE7;&#xE3;o da &#xE1;gua para a terra. Esse ambiente terrestre era relativamente n&#xE3;o colonizado e dispunha de recursos abundantes. Os ambientes terrestres tamb&#xE9;m ofereciam mais luz e di&#xF3;xido de carbono, necess&#xE1;rios para que as plantas crescessem e sobrevivessem.
No entanto, as acentuadas diferen&#xE7;as entre a terra e o mar representaram um desafio formid&#xE1;vel para as primeiras esp&#xE9;cies colonizadoras, levando ao surgimento de muitas novas adapta&#xE7;&#xF5;es que resultaram na grande variedade de formas vegetais observada atualmente.
Uma das primeiras adapta&#xE7;&#xF5;es foi o desenvolvimento de um revestimento ceroso externo, denominado cut&#xED;cula. As cut&#xED;culas servem para proteger as plantas contra a desseca&#xE7;&#xE3;o, retendo a umidade em seu interior. No entanto, essa adapta&#xE7;&#xE3;o impedia a troca direta de gases pela superf&#xED;cie das plantas. Como resultado, desenvolveram-se poros nas superf&#xED;cies externas das plantas, que permitiam a absor&#xE7;&#xE3;o de di&#xF3;xido de carbono e a libera&#xE7;&#xE3;o de oxig&#xEA;nio.
Estruturas adicionais foram necess&#xE1;rias para facilitar o transporte de &#xE1;gua e nutrientes do solo para as partes superiores da planta. Como resultado, desenvolveu-se o tecido vascular, que n&#xE3;o apenas serve para transportar &#xE1;gua e nutrientes para todas as regi&#xF5;es da planta, mas tamb&#xE9;m fornece sustenta&#xE7;&#xE3;o estrutural &#xE0; medida que os caules crescem e se tornam mais altos e resistentes.
Para possibilitar a reprodu&#xE7;&#xE3;o em terra, as plantas terrestres desenvolveram gamet&#xE2;ngios&#x2014;estruturas reprodutivas que protegem os gametas e os embri&#xF5;es contra as condi&#xE7;&#xF5;es adversas do ambiente externo &#xE0; planta. Nos indiv&#xED;duos masculinos, essa estrutura &#xE9; denominada anter&#xED;dio, enquanto, nos indiv&#xED;duos femininos, &#xE9; denominada arqueg&#xF4;nio.
Diferentes estrat&#xE9;gias evolu&#xED;ram para facilitar o transporte dos espermatozoides dos anter&#xED;dios at&#xE9; as oosferas no interior dos arqueg&#xF4;nios. Entre elas est&#xE3;o o deslocamento dos espermatozoides por nata&#xE7;&#xE3;o de uma estrutura para outra, ou o transporte do p&#xF3;len pelo vento ou por polinizadores, como abelhas e aves. O modo espec&#xED;fico utilizado &#xE9; pr&#xF3;prio de cada classifica&#xE7;&#xE3;o de plantas. Ap&#xF3;s a fertiliza&#xE7;&#xE3;o, as oosferas s&#xE3;o retidas no interior dos arqueg&#xF4;nios para proteger e nutrir o embri&#xE3;o em desenvolvimento, ou espor&#xF3;fito.
Outra importante adapta&#xE7;&#xE3;o reprodutiva foi a forma&#xE7;&#xE3;o de sementes. Embora nem todas as plantas terrestres produzam sementes, elas s&#xE3;o vantajosas por muitas raz&#xF5;es. Sem essas estruturas, as plantas necessitam de ambientes &#xFA;midos para transportar os gametas de um local para outro. Frequentemente, nas plantas sem sementes, os esporos t&#xEA;m aproximadamente o mesmo tamanho (hom&#xF3;sporos) e se dispersam de forma independente. No entanto, as plantas com sementes geralmente apresentam pequenos esporos masculinos adaptados para apresentar alta mobilidade, denominados gr&#xE3;os de p&#xF3;len, que se deslocam at&#xE9; os gamet&#xF3;fitos femininos para levar os espermatozoides at&#xE9; a oosfera por meio de um tubo pol&#xED;nico. Ap&#xF3;s a fertiliza&#xE7;&#xE3;o, forma-se uma semente que cont&#xE9;m o embri&#xE3;o vegetal e uma reserva de nutrientes.
Essas adapta&#xE7;&#xF5;es deram origem a esp&#xE9;cies vegetais bem adaptadas &#xE0; vida em ambientes terrestres.
Principais linhagens de plantas
Embora atualmente existam in&#xFA;meras variedades de plantas, todas podem ser divididas em um de tr&#xEA;s grupos: n&#xE3;o vasculares, vasculares sem sementes e vasculares com sementes. As plantas n&#xE3;o vasculares s&#xE3;o as mais ancestrais e menos complexas, incluindo musgos, hep&#xE1;ticas e ant&#xF3;ceros. Essas plantas n&#xE3;o possuem tecido vascular (xilema e floema); a &#xE1;gua e os nutrientes se deslocam pela planta principalmente por difus&#xE3;o, osmose e a&#xE7;&#xE3;o capilar. Em seguida, as plantas vasculares sem sementes incluem samambaias e cavalinhas e foram o primeiro grupo a desenvolver um sistema de transporte vascular. O &#xFA;ltimo grupo, as plantas vasculares com sementes, inclui todas as esp&#xE9;cies restantes. Esse grupo &#xE9; o mais diverso e ocupa a maior variedade de habitats, sendo dividido em dois grandes subgrupos: angiospermas e gimnospermas. As angiospermas incluem todas as plantas com flores e frutos, cujo p&#xF3;len &#xE9; transportado pelo vento ou por polinizadores. As gimnospermas s&#xE3;o plantas sem flores, incluindo con&#xED;feras, cicad&#xF3;fitas e &#xE1;rvores de ginkgo. Essas esp&#xE9;cies produzem sementes nuas, que n&#xE3;o s&#xE3;o protegidas por frutos, e seu p&#xF3;len &#xE9; transportado pelo vento.

Introdução à diversidade vegetal

From Water to Land

Kingdom Plantae first appeared about 410 million years ago as green algae transitioned from water to land. This land was a relatively ...

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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

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 across the plant surface. To solve that problem, pores formed on the outside of plants so carbon dioxide could enter and oxygen could leave.

Plants also needed a way to move water and nutrients upward from the soil. Vascular tissue evolved for this job. It transports water and nutrients throughout the plant and gives stems support as they grow taller and stronger. Reproduction on land brought another challenge, so terrestrial plants developed gametangia, which are structures that protect gametes and embryos from the dry environment outside the plant. In males, this structure is called antheridia, and in females, it is called archegonia.

Different plants use different ways to move sperm from antheridia to eggs in archegonia. In some cases, sperm swim from one structure to the next. In others, wind carries them, or pollinators such as bees and birds transport them. After fertilization, eggs stay inside the archegonia, where the developing embryo, or sporophyte, is protected and nourished.

Seeds were another major step in plant evolution on land. Not all terrestrial plants have seeds, but seeds help plants survive in dry environments. Seedless plants often need moist conditions because male and female spores are about the same size and both travel. Seeded plants usually produce small male spores called pollen grains. These are highly mobile and move to female gametophytes, where sperm is delivered directly to the egg. After fertilization, a seed forms and contains the embryo plus a nutrient supply.

These adaptations produced the many plant forms seen today. Plant species are grouped into three major lineages: non-vascular, vascular seedless, and vascular seeded. Non-vascular plants are the most ancestral and least complex. They include mosses, liverworts, and hornworts. Vascular seedless plants include ferns and horsetails, and they were the first plants to evolve a vascular transport system.

The most diverse group is the vascular seeded plants, which occupy the broadest range of habitats. This group is split into angiosperms and gymnosperms. Angiosperms are flowering and fruiting plants, and their pollen is carried by wind or by pollinators. Gymnosperms are non-flowering plants such as conifers, cycads, and ginkgo trees. They produce bare seeds that are not protected by fruit, and their pollen is carried by wind.

Plant Adaptations for Life on Land

introduction to plant diversity

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

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...

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

Explore how plants adapted to land with cuticles, vascular tissue, gametangia, seeds, and the three major plant lineages in grades 9–12 biology.

Plant Adaptations for Life on Land | 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.

new-york-state-science-learning-standards

New York State Science Learning Standards

Earth and Space Sciences

Earth’s Systems

HS-ESS2-7.

Georgia Standards of Excellence

9-12

Botany

SBO1.

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

Change in plant straucture through geological time

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SC.912.L.14.1

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Endoplasmic Reticulum

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Exocytosis is used to release material from cells. Like other bulk transport mechanisms, exocytosis requires energy.

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

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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 ...

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.

Plant Adaptations for Life on Land

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