Name: plant features that limit water loss
Uploaded: 2026-08-26T08:20:34.350Z
Duration: 2 min 35 s
Channel: JoVE

K12 Standards

Virginia  Standards of Learning

HIgh School

Life Science

LS.7

LS.7.b

Adaptations that Reduce Water Loss

L&#x27;acqua &#xE8; fondamentale per le piante
per effettuare la fotosintesi, il metabolismo

e conservare la struttura cellulare.

Inoltre, l&#x27;eccessiva perdita d&#x27;acqua
crea problemi alle piante.

Quali adattamenti ha assunto
la pianta per sopportare

e contrastare la perdita idrica?

In genere le piante hanno
una cuticola cerosa

che copre la superficie
fogliare, prevenendo

l&#x27;evaporazione dell&#x27;acqua.

La particolare composizione
della cuticola influisce sulle

minuscole aperture della superficie,
denominate stomi,

facilitando lo scambio dei gas e la traspirazione.

Per minimizzare la perdita d&#x27;acqua, le piante
regolano la densit&#xE0; e la posizione

degli stomi, e sviluppano
foglie in risposta

alla disponibilit&#xE0; di acqua e luce.

Nella maggior parte degli
alberi decidui,

gli stomi sono situati sulla
parte inferiore delle foglie.

Inoltre, la densit&#xE0; degli stomi

&#xE8; pi&#xF9; alta sulle foglie
vicine al centro dell&#x27;albero

e pi&#xF9; bassa sulle foglie
nelle zone periferiche.

La conservazione dell&#x27;acqua
&#xE8; essenziale

soprattutto per le piante
in zone desertiche.

L&#x27;arbusto desertico Encelia farinosa
cattura l&#x27;acqua intorno alle foglie

grazie a minuscole ciglia.

Queste ciglia, dette tricomi,
deviano la luce solare

e riducono l&#x27;effetto essicante del vento.

Altre piante desertiche,
come l&#x27;Opuntia,

immagazzina acqua nello stelo carnoso

per proteggersi dalla siccit&#xE0;.

Inoltre, i cactus hanno foglie modificate,
denominate spine,

che riducono l&#x27;evaporazione
e diradano il calore.

Le piante di ambienti aridi
sono in grado di

ridurre l&#x27;evaporazione semplicemente
assorbendo l&#x27;anidride carbonica

durante la notte.

Durante il giorno gli stomi restano chiusi.

Questo processo &#xE8; chiamato
metabolismo acido delle Crassulacee

o CAM.

Anche una specifica architettura fogliare
pu&#xF2; ridurre la perdita di acqua.

Le foglie piccole o fini
riducono l&#x27;evaporazione.

Le erbe hanno elaborato
strutture fogliari in grado

di piegarsi o arrotolarsi,
riducendo la superficie

e quindi l&#x27;evaporazione.

Buckley, Thomas N., Grace P. John, Christine Scoffoni, e Lawren Sack. "I siti di evaporazione all'interno delle foglie." Fisiologia Vegetale 173, n. 3 (2017): 1763-1782. [<a href="https://www.ncbi.nlm.nih.gov/pubmed/28153921" target="_blank">Source</a>]

Borland, et al. "Agroforestazione resiliente al clima: risposte fisiologiche ai cambiamenti climatici e ingegneria del metabolismo acido delle crassulacee (CAM) come strategia di mitigazione." Plant, Cell & Environment 38, n. 9 (2015): 1833-1849. [<a href="https://www.ncbi.nlm.nih.gov/pubmed/25366937" target="_blank">Fonte</a>]

Yang X et al. Una tabella di marcia per la ricerca sul metabolismo acido delle crassulacee (CAM) per migliorare la produzione sostenibile di cibo e bioenergia in un mondo più caldo e secco. Nuovo Phytol. Agosto 2015; 207(3):491-504. [<a href="https://www.ncbi.nlm.nih.gov/pubmed/26153373" target="_blank">Sorgente</a>]

Jalakas, Pirko, Ebe Merilo, Hannes Kollist e Mikael Brosché. "La regolazione della densità stomatica mediata da ABA è indipendente da OST1." Plant Direct 2, n. 9 (1 settembre 2018). [<a href="https://doi.org/10.1002/pld3.82" target="_blank">Sorgente</a>]

adattamenti che riducono la perdita dell'acqua

Anche se l&#x27;evaporazione dall&#x27;impianto lascia unit&#xE0; traspirazione, si traduce anche in perdita di acqua. Poich&#xE9; l&#x27;acqua &#xE8; fondamentale per le reazioni fotosintetiche e altri processi cellulari, le pressioni evolutive sulle piante in ambienti diversi hanno guidato l&#x27;acquisizione di adattamenti che riducono la perdita d&#x27;acqua.
Nelle piante terrestri, lo strato cellulare pi&#xF9; in alto di una foglia vegetale, chiamata epidermide, &#xE8; rivestito con una sostanza cerosa chiamata cuticola. Questo strato idrofobico &#xE8; composto dal polimero cutina e da altre cere di origine vegetale che sono sintetizzate da cellule epidermiche. Queste sostanze prevengono la perdita di acqua indesiderata e l&#x27;ingresso di soluti non necessari. La composizione e lo spessore specifici della cuticola variano a seconda delle specie vegetali e dell&#x27;ambiente. Altri adattamenti foglia possono anche ridurre al minimo l&#x27;evaporazione, principalmente riducendo la superficie. Ad esempio, alcune erbe hanno una struttura piegata che riduce la perdita d&#x27;acqua. In alternativa, altre specie di erba subiscono un rotolamento della lama per proteggere contro l&#x27;evaporazione. Alcune piante che abitano il deserto hanno foglie rivestite di peli microscopici che intrappolano il vapore acqueo, riducendo cos&#xEC; l&#x27;evaporazione.
L&#x27;acqua evapora principalmente attraverso piccoli fori in foglie vegetali chiamati stomi. Gli stomi di alcune piante si trovano esclusivamente sulla superficie inferiore della foglia, proteggendoli dall&#x27;eccessiva evaporazione associata al calore. Altre piante intrappolano il vapore acqueo vicino agli stomi che si trovano in fosse sulle loro foglie, riducendo la perdita di acqua evaporativa, poich&#xE9; le cellule di guardia che fiancheggiano l&#x27;apertura stomatale possono percepire l&#x27;umidit&#xE0; relativa. Alcune piante del deserto aprono i loro stomi solo di notte, quando &#xE8; meno probabile che si verifichi l&#x27;evaporazione. Questa strategia &#xE8; chiamata Crassulacean Acid Metabolism (CAM), e le piante che lo usano catturano e fissano l&#x27;anidride carbonica di notte, e corrono reazioni fotosintetiche dipendenti dalla luce durante il giorno. Alcuni scienziati hanno proposto impianti di bioingegneria per disaccoppiare la fissazione del carbonio dalla fotosintesi utilizzando la CAM come sforzo di mitigazione per l&#x27;evaporazione associata al riscaldamento delle temperature globali.

Adattamenti che riducono la perdita dell'acqua

Though evaporation from plant leaves drives transpiration, it also results in loss of water. Because water is critical for photosynthetic reactions and ...

https://cloudfront.jove.com/files/ftp_upload/11100/11100_article_thumb_11100.jpg

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 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 thickness and makeup vary with plant species and growing conditions.

Some plants also reduce water loss by changing leaf shape. Certain grasses have folded leaves, and others roll their leaf blades to limit evaporation. Desert plants may have microscopic hairs on their leaves that trap water vapor and slow water loss.

Most water leaves a plant through stomata, which are tiny openings in the leaf. In some plants, stomata are found only on the lower leaf surface, where they are less exposed to heat. Other plants place stomata in pits, where trapped water vapor raises humidity around the guard cells and lowers evaporation.

A few desert plants use Crassulacean Acid Metabolism, or CAM. These plants open their stomata at night, when evaporation is lower, and capture carbon dioxide then. During the day, they carry out the light-dependent reactions of photosynthesis. Scientists have also suggested using CAM in bioengineering to help plants cope with warming global temperatures.

Plant Features That Limit Water Loss

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

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 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 leaf cuticle, stomata, leaf shape, hairs, and CAM photosynthesis adaptations that help plants reduce water loss in dry environments.

Plant Features That Limit Water Loss | 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.

Florida Department of Education

High School

SC.912.L.14

SC.912.L.14.7

Georgia Standards of Excellence

9-12

Botany

SBO1.

Transport

What is an Ecosystem?

Overview

An ecosystem is the interaction between all abiotic and biotic factors in an environment and can be classified as terrestrial or aquatic. ...

What is Biodiversity?

Biodiversity describes the variety of living things at multiple organizational levels: genetic, species and ecosystem diversity. Species diversity ...

The Soil Ecosystem

Plants obtain inorganic minerals and water from the soil, which acts as a natural medium for land plants. The composition and quality of soil depend not ...

The student will investigate and understand that adaptations support an organism's survival in an ecosystem. Key ideas include biotic and abiotic factors define land, marine, and freshwater ecosystems; and

LS.7.a

Plant Hormones

Plant hormones&mdash;or phytohormones&mdash;are chemical molecules that modulate one or more physiological processes of a plant. In animals, hormones are ...

photoreceptors-and-plant-responses-to-light

Photoreceptors and Plant Responses to Light

Light plays a significant role in regulating the growth and development of plants. In addition to providing energy for photosynthesis, light provides ...

Biological Clocks and Seasonal Responses

The circadian&#8212;or biological&#8212;clock is an intrinsic, timekeeping, molecular mechanism that allows plants to coordinate physiological activities ...

Responses to Gravity and Touch

Gravitropism: Plant Responses to Gravity

Higher plants sense gravity using statocytes, cells found near the vascular tissue in shoots, and in the root ...

Responses to Drought and Flooding

Water plays a significant role in the life cycle of plants. However, insufficient or excess of water can be detrimental and pose a serious threat to ...

Responses to Heat and Cold Stress

Every organism has an optimum temperature range within which healthy growth and physiological functioning can occur. At the ends of this range, there will ...

Responses to Salt Stress

Salt stress&mdash;which can be triggered by high salt concentrations in a plant&rsquo;s environment&mdash;can significantly affect plant growth and crop ...

defenses-against-pathogens-and-herbivores

Defenses Against Pathogens and Herbivores

Plants present a rich source of nutrients for many organisms, making it a target for herbivores and infectious agents. Plants, though lacking a proper ...

Migration

Migration is long-range, seasonal movement from one region or habitat to another. This common strategy, carried out by many different organisms around the ...

Communication

Communication between two animals occurs when one animal transmits an information signal that causes a change in the animal that receives the information. ...

Mate Choice

Mate choice&#8212;the decision about whom to mate with&#8212;is a type of natural selection, since animals must reproduce to pass down their genes. Mate ...

Optimal Foraging

How animals obtain and eat their food is called foraging behavior. Foraging can include searching for plants and hunting for prey and depends on the ...

The student will investigate and understand that adaptations support an organism's survival in an ecosystem. Key ideas include physical and behavioral characteristics enable organisms to survive within a specific ecosystem.

Plant Features That Limit Water Loss

Description

Transcript

Tags

More videos by Standards