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

Prima che le piante colonizzassero
la terra dal mare,

i continenti erano aridi.

Oggi milioni di specie di microbi,
piante e animali

popolano la terra, ed &#xE8; stata
l&#x27;evoluzione delle piante terrestri

a rendere possibile tutto ci&#xF2;.

Per comprendere questa incredibile trasformazione,

&#xE8; necessario in primo luogo capire

cosa esattamente sono le piante,
e come sono evolute per affrontare

la sfida della vita sulla terra.

Ci sono alcune caratteristiche

che condividono tutte le piante,
dagli alberi pi&#xF9; alti

al pi&#xF9; piccolo muschio.

Innanzitutto, tutte le piante
sono eucarioti multicellulari.

In secondo luogo, le piante creano
il pigmento fotosintetico,

la clorofilla, negli organelli
chiamati cloroplasti,

permettendo loro di produrre
il proprio cibo usando l&#x27;energia

del sole.

In terzo luogo, tutte le piante
hanno cellule circondate

da pareti di cellulosa.

Infine, tutte le piante
hanno un ciclo di vita

caratterizzato dall&#x27;alternanza di generazioni,

definita come la transizione
tra stadi multicellulari

aploidi e diploidi durante il ciclo vitale.

Per generazioni si intendono
due diverse fasi multicellulari

nel ciclo vitale.

Una fase &#xE8; il gametofito aploide.

Il gametofito produce
gameti mediante mitosi,

che si fondono durante la fecondazione
a formare una cellula diploide,

che subisce poi la mitosi
per trasformarsi in uno sporofito.

Lo sporofito, a sua volta, produce spore aploidi

tramite meiosi, e completa
il ciclo dando origine

a nuovi gametofiti.

Bench&#xE9; tutte le piante condividano
queste caratteristiche,

ci sono forti differenze
tra i diversi lignaggi vegetali

nel modo in cui si esprimono
alcune di queste caratteristiche.

Le piante terrestri si dividono in
tre gruppi principali: le non vascolari,

le piante vascolari senza semi
e le piante da seme.

Ciascuno di questi gruppi contiene
molte migliaia di specie.

Con il progredire del tempo
evolutivo, i tre gruppi

hanno sviluppato tratti
diversi caratterizzanti -

dal tessuto vascolare
all&#x27;evoluzione dei frutti.

Nel loro insieme, questi adattamenti hanno
consentito alle piante

di dominare la maggior
parte dei biomi terrestri.

Ziv, C., et al. (2018). "Ruoli multifunzionali della cuticola della pianta durante le interazioni pianta-patogeno". Front Plant Sci 9: 1088. [<a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6068277/">Sorgente</a>]

Gupta, R. e R. Deswal (2014). "Le proteine antigelo consentono alle piante di sopravvivere in condizioni di congelamento." J Biosci 39(5): 931-944. [<a href="http://www.plantphysiol.org/content/138/1/330">Sorgente</a>]

introduzione alla diversità delle piante

Dall&#x27;acqua alla terraferma
Il regno Plantae comparve per la prima volta circa 470 milioni di anni fa, quando le alghe verdi carofite passarono dall&#x27;acqua alla terraferma. La terraferma costituiva un ambiente relativamente non colonizzato e ricco di risorse. Gli ambienti terrestri offrivano inoltre una maggiore quantit&#xE0; di luce e di anidride carbonica, necessarie alle piante per crescere e sopravvivere.
Tuttavia, le marcate differenze tra la terraferma e il mare rappresentarono una sfida considerevole per le prime specie colonizzatrici, favorendo l&#x27;evoluzione di numerosi nuovi adattamenti che hanno dato origine all&#x27;ampia variet&#xE0; di forme vegetali osservata oggi.
Uno dei primi adattamenti fu lo sviluppo di un rivestimento ceroso esterno, chiamato cuticola. Le cuticole servono a proteggere le piante dal disseccamento, trattenendo l&#x27;umidit&#xE0; al loro interno. Tuttavia, questo adattamento impediva lo scambio diretto di gas attraverso la superficie delle piante. Di conseguenza, sulle superfici esterne delle piante si svilupparono pori che consentivano l&#x27;assorbimento dell&#x27;anidride carbonica e il rilascio dell&#x27;ossigeno.
Erano necessarie ulteriori strutture per facilitare il trasporto di acqua e sostanze nutritive dal suolo alle parti superiori della pianta. Di conseguenza, si svilupp&#xF2; il tessuto vascolare, che non solo serve a trasportare acqua e sostanze nutritive in tutte le aree della pianta, ma fornisce anche sostegno strutturale man mano che i fusti crescono in altezza e robustezza.
Per consentire la riproduzione sulla terraferma, le piante terrestri svilupparono i gametangi&#x2014;strutture riproduttive che proteggono i gameti e gli embrioni dalle difficili condizioni dell&#x27;ambiente esterno alla pianta. Nei gametangi maschili, questa struttura &#xE8; chiamata anteridio, mentre in quelli femminili &#xE8; chiamata archegonio.
Si evolsero diverse strategie per facilitare il trasporto degli spermatozoidi dagli anteridi alle cellule uovo presenti negli archegoni. Queste comprendono il movimento degli spermatozoidi da una struttura all&#x27;altra oppure il trasporto del polline da parte del vento o di impollinatori come api e uccelli. La modalit&#xE0; specifica utilizzata &#xE8; propria di ciascuna classificazione delle piante. In seguito alla fecondazione, le cellule uovo vengono trattenute all&#x27;interno degli archegoni per proteggere e nutrire l&#x27;embrione in via di sviluppo, o sporofito.
Un altro importante adattamento riproduttivo fu la produzione di semi. Sebbene non tutte le piante terrestri producano semi, i semi sono vantaggiosi per molte ragioni. In assenza di queste strutture, le piante necessitano di ambienti umidi per trasportare i gameti da un luogo all&#x27;altro. Spesso, nelle piante senza semi, le spore hanno dimensioni approssimativamente uguali (omosporiche) e si spostano indipendentemente. Tuttavia, le piante con semi contengono generalmente piccole spore maschili adattate a essere altamente mobili, chiamate granuli pollinici, che raggiungono i gametofiti femminili per trasferire i gameti maschili alla cellula uovo attraverso un tubetto pollinico. Una volta avvenuta la fecondazione, si forma un seme che contiene l&#x27;embrione vegetale e una riserva di sostanze nutritive.
Questi adattamenti hanno dato origine a specie vegetali ben adattate alla vita negli ambienti terrestri.
Principali linee evolutive delle piante
Sebbene oggi esistano innumerevoli variet&#xE0; di piante, tutte possono essere suddivise in uno dei tre gruppi seguenti: non vascolari, vascolari senza semi e vascolari con semi. Le piante non vascolari rappresentano il gruppo pi&#xF9; ancestrale e meno complesso e comprendono muschi, epatiche e antocerote. Queste piante sono prive di tessuto vascolare (xilema e floema); l&#x27;acqua e le sostanze nutritive si spostano attraverso la pianta principalmente mediante diffusione, osmosi e capillarit&#xE0;. Le piante vascolari senza semi comprendono invece felci ed equiseti e furono il primo gruppo a evolvere un sistema di trasporto vascolare. L&#x27;ultimo gruppo, quello delle piante vascolari con semi, comprende tutte le altre specie. Questo gruppo &#xE8; il pi&#xF9; diversificato, occupa la pi&#xF9; ampia gamma di habitat ed &#xE8; suddiviso in due principali sottogruppi, le angiosperme e le gimnosperme. Le angiosperme comprendono tutte le piante che producono fiori e frutti, con polline trasportato dal vento o dagli impollinatori. Le gimnosperme sono piante prive di fiori, tra cui conifere, cicadi e alberi di ginkgo. Queste specie producono semi nudi, non protetti da frutti, e il polline viene trasportato dal vento.

Introduzione alla diversità delle piante

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

Didattica

JoVE Core

Biology

Biologia

Plant Biology

Biologia vegetale

Plant Structure, Growth and Function

Struttura, crescita e nutrizione delle piante

KEY TERMS AND CONCEPTS

TERMINI E CONCETTI CHIAVE

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

JoVE Core Biologia illustra i concetti chiave della biologia grazie a oltre 300 video-lezioni animate, concise e di facile comprensione. Inoltre, negli oltre 150 video di "scienziati in azione", i concetti scientifici vengono applicati e dimostrati da ricercatori attraverso esperimenti in laboratorio.

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

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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Animal and Plant Cell Structure

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Chemistry of the Cell

The cell is chemically composed of water, organic molecules and inorganic ions.
Water
The polarity of the water molecule and its resulting hydrogen ...

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

The nucleus is a membrane-bound organelle that acts as a control center in a eukaryotic cell. It contains chromosomal DNA, which controls gene expression ...

Endoplasmic Reticulum

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Ribosomes

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Golgi Apparatus

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Microtubules

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Gap Junctions

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The Extracellular Matrix

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Tissues

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Plant Cell Wall

The plant cell wall gives plant cells shape, support, and protection. As a cell matures, its cell wall specializes according to the cell type. For ...

Plasmodesmata

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Osmosis

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Tonicity in Animals

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Tonicity in Plants

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Facilitated Transport

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Secondary Active Transport

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Receptor-mediated Endocytosis

Overview

Receptor-mediated endocytosis is a process through which bulk amounts of specific molecules can be imported into a cell after binding to cell ...

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 ...

Phagocytosis

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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
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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

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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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