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

Avant que les plantes ne colonisent la terre depuis la mer,les continents &#xE9;taient st&#xE9;riles. 
Aujourd&#x27;hui, des millions d&#x27;esp&#xE8;ces de microbes, de plantes et d&#x27;animauxvivent sur la terre, et c&#x27;&#xE9;tait l&#x27;&#xE9;volution des plantes terrestresqui a rendu tout cela possible. 
Pour comprendre cette transformation stup&#xE9;fiante,il faut d&#x27;abord comprendrece que sont exactement les plantes, et comment elles ont &#xE9;volu&#xE9; pour r&#xE9;pondreles d&#xE9;fis de la vie sur terre. 
Il existe certaines caract&#xE9;ristiquesque toutes les plantes partagent, des plus grands arbres&#xE0; la plus petite mousse. 
Tout d&#x27;abord, toutes les plantes sont des eucaryotes multicellulaires. 
Deuxi&#xE8;mement, les plantes produisent le pigment photosynth&#xE9;tiquechlorophylle dans les organes appel&#xE9;es chloroplastes,leur permettant de produire leur propre nourriture en utilisant de l&#x27;&#xE9;nergiedu soleil. 
Troisi&#xE8;mement, toutes les plantes ont des cellules qui sont entour&#xE9;espar des murs en cellulose. 
Enfin, toutes les plantes ont un cycle de viecaract&#xE9;ris&#xE9; par l&#x27;alternance des g&#xE9;n&#xE9;rations,d&#xE9;finie comme la transition entre l&#x27;haplo&#xEF;de et le diplo&#xEF;deou stades multicellulaires au cours du cycle de vie. 
Ici, les g&#xE9;n&#xE9;rations se r&#xE9;f&#xE8;rent &#xE0; deux diff&#xE9;rents stades multicellulairesles phases du cycle de vie. 
L&#x27;une de ces phases est le gam&#xE9;tophyte naplo&#xEF;de. 
Le gam&#xE9;tophyte produit des gam&#xE8;tes par mitose,qui fusionnent pendant la f&#xE9;condation pour former une cellule diplo&#xEF;de, quipuis subit une mitose pour se d&#xE9;velopper en sporophyte. 
Le sporophyte, &#xE0; son tour, produit des spores haplo&#xEF;despar la m&#xE9;iose, compl&#xE9;tant le cycle en donnant naissanceaux nouveaux gam&#xE9;tophytes. 
Bien que toutes les plantes partagent ces caract&#xE9;ristiques,il y a de grandes diff&#xE9;rences entre les diff&#xE9;rentes plantesdans la fa&#xE7;on dont certaines de ces caract&#xE9;ristiques sont exprim&#xE9;es. 
Les plantes terrestres se r&#xE9;partissent en trois grands groupes, les plantes non vasculairesles plantes, les plantes vasculaires sans graines et les plantes &#xE0; graines. 
Chacun de ces groupes contient plusieurs milliers d&#x27;esp&#xE8;ces. 
Au fil de l&#x27;&#xE9;volution, les trois groupesa &#xE9;volu&#xE9; de diff&#xE9;rents traits qui les caract&#xE9;risent -des tissus vasculaires, &#xE0; l&#x27;&#xE9;volution des fruits. 
Ensemble, ces adaptations ont permis aux plantesde dominer la plupart des biomes terrestres.

Ziv, C., et al. (2018). « Rôles multifonctionnels de la cuticule végétale lors des interactions plante-pathogène. » Front Plant Sci 9 : 1088. [<a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6068277/">Source</a>]

Gupta, R. et R. Deswal (2014). « Les protéines antigel permettent aux plantes de survivre dans des conditions de congélation. » J Biosci 39(5) : 931-944. [<a href="http://www.plantphysiol.org/content/138/1/330">Source</a>]

introduction à la diversité végétale

De l&#x2019;eau &#xE0; la terre ferme
Le r&#xE8;gne Plantae est apparu pour la premi&#xE8;re fois il y a environ 470 millions d&#x2019;ann&#xE9;es, lorsque les algues vertes charophytes sont pass&#xE9;es du milieu aquatique au milieu terrestre. La terre ferme constituait alors un environnement relativement peu colonis&#xE9;, dot&#xE9; de ressources abondantes. Les environnements terrestres offraient &#xE9;galement davantage de lumi&#xE8;re et de dioxyde de carbone, n&#xE9;cessaires &#xE0; la croissance et &#xE0; la survie des plantes.
Cependant, les diff&#xE9;rences marqu&#xE9;es entre la terre et la mer ont constitu&#xE9; un d&#xE9;fi consid&#xE9;rable pour les premi&#xE8;res esp&#xE8;ces colonisatrices, favorisant l&#x2019;apparition de nombreuses adaptations nouvelles &#xE0; l&#x2019;origine de la grande diversit&#xE9; des formes v&#xE9;g&#xE9;tales observ&#xE9;es aujourd&#x2019;hui.
L&#x2019;une des premi&#xE8;res adaptations a &#xE9;t&#xE9; le d&#xE9;veloppement d&#x2019;un rev&#xEA;tement cireux externe, appel&#xE9; cuticule. Les cuticules servent &#xE0; prot&#xE9;ger les plantes contre la dessiccation en retenant l&#x2019;humidit&#xE9; &#xE0; l&#x2019;int&#xE9;rieur. Cependant, cette adaptation emp&#xEA;chait les &#xE9;changes gazeux directs &#xE0; travers la surface des plantes. Par cons&#xE9;quent, des pores se sont d&#xE9;velopp&#xE9;s &#xE0; la surface des plantes, permettant l&#x2019;absorption du dioxyde de carbone et la lib&#xE9;ration d&#x2019;oxyg&#xE8;ne.
Des structures suppl&#xE9;mentaires &#xE9;taient n&#xE9;cessaires pour faciliter le transport de l&#x2019;eau et des nutriments depuis le sol jusqu&#x2019;aux parties sup&#xE9;rieures de la plante. Par cons&#xE9;quent, un tissu vasculaire s&#x2019;est d&#xE9;velopp&#xE9;, qui non seulement sert &#xE0; transporter l&#x2019;eau et les nutriments vers toutes les parties de la plante, mais assure &#xE9;galement un soutien structurel &#xE0; mesure que les tiges deviennent plus hautes et plus robustes.
Pour permettre la reproduction sur la terre ferme, les plantes terrestres ont d&#xE9;velopp&#xE9; des gam&#xE9;tanges &#x2014; des structures reproductrices qui prot&#xE8;gent les gam&#xE8;tes et les embryons contre les conditions difficiles du milieu ext&#xE9;rieur &#xE0; la plante. Chez les m&#xE2;les, cette structure est appel&#xE9;e l&#x2019;anth&#xE9;ridie, tandis que chez les femelles, elle est appel&#xE9;e l&#x2019;arch&#xE9;gone.
Diff&#xE9;rentes strat&#xE9;gies ont &#xE9;volu&#xE9; afin de faciliter le transport des spermatozo&#xEF;des depuis les anth&#xE9;ridies jusqu&#x2019;aux oosph&#xE8;res situ&#xE9;es dans les arch&#xE9;gones. Parmi celles-ci figurent le d&#xE9;placement des spermatozo&#xEF;des &#xE0; la nage d&#x2019;une structure &#xE0; l&#x2019;autre, ou le transport du pollen par le vent ou par des pollinisateurs tels que les abeilles et les oiseaux. Le mode pr&#xE9;cis utilis&#xE9; est propre &#xE0; chaque classification des plantes. Apr&#xE8;s la f&#xE9;condation, les oosph&#xE8;res sont conserv&#xE9;es dans les arch&#xE9;gones afin de prot&#xE9;ger et de nourrir l&#x2019;embryon en d&#xE9;veloppement, ou sporophyte.
Une autre adaptation reproductive majeure a &#xE9;t&#xE9; l&#x2019;apparition des graines. Bien que toutes les plantes terrestres ne produisent pas de graines, celles-ci pr&#xE9;sentent de nombreux avantages. Sans ces structures, les plantes ont besoin de milieux humides pour transporter les gam&#xE8;tes d&#x2019;un endroit &#xE0; un autre. Souvent, chez les plantes sans graines, les spores sont approximativement de la m&#xEA;me taille (homospores) et se d&#xE9;placent ind&#xE9;pendamment. Cependant, les plantes &#xE0; graines produisent g&#xE9;n&#xE9;ralement de petites spores m&#xE2;les adapt&#xE9;es &#xE0; une grande mobilit&#xE9;, appel&#xE9;es grains de pollen, qui se d&#xE9;placent jusqu&#x2019;aux gam&#xE9;tophytes femelles afin d&#x2019;acheminer les spermatozo&#xEF;des jusqu&#x2019;&#xE0; l&#x2019;oosph&#xE8;re par l&#x2019;interm&#xE9;diaire d&#x2019;un tube pollinique. Une fois la f&#xE9;condation r&#xE9;alis&#xE9;e, une graine se forme, contenant l&#x2019;embryon v&#xE9;g&#xE9;tal et une r&#xE9;serve de nutriments.
Ces adaptations ont donn&#xE9; naissance &#xE0; des esp&#xE8;ces v&#xE9;g&#xE9;tales bien adapt&#xE9;es &#xE0; la vie dans les environnements terrestres.
Principales lign&#xE9;es de plantes
Bien qu&#x2019;il existe aujourd&#x2019;hui d&#x2019;innombrables vari&#xE9;t&#xE9;s de plantes, elles peuvent toutes &#xEA;tre r&#xE9;parties en trois groupes : les plantes non vasculaires, les plantes vasculaires sans graines et les plantes vasculaires &#xE0; graines. Les plantes non vasculaires sont les plus ancestrales et les moins complexes ; elles comprennent les mousses, les h&#xE9;patiques et les anthoc&#xE9;rotes. Ces plantes sont d&#xE9;pourvues de tissu vasculaire (xyl&#xE8;me et phlo&#xE8;me) ; l&#x2019;eau et les nutriments se d&#xE9;placent principalement dans la plante par diffusion, osmose et capillarit&#xE9;. Viennent ensuite les plantes vasculaires sans graines, qui comprennent les foug&#xE8;res et les pr&#xEA;les et qui ont &#xE9;t&#xE9; le premier groupe &#xE0; d&#xE9;velopper un syst&#xE8;me de transport vasculaire. Le dernier groupe, celui des plantes vasculaires &#xE0; graines, comprend toutes les autres esp&#xE8;ces. Ce groupe est le plus diversifi&#xE9; et occupe la plus vaste gamme d&#x2019;habitats ; il se divise en deux grands sous-groupes, les angiospermes et les gymnospermes. Les angiospermes comprennent toutes les plantes &#xE0; fleurs et &#xE0; fruits, dont le pollen est transport&#xE9; par le vent ou par des pollinisateurs. Les gymnospermes sont des plantes sans fleurs, parmi lesquelles figurent les conif&#xE8;res, les cycadales et les ginkgos. Ces esp&#xE8;ces produisent des graines nues, non prot&#xE9;g&#xE9;es par un fruit, et leur pollen est transport&#xE9; par le vent.

Introduction à la diversité végétale

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

Enseignement

JoVE Core

Biology

Biologie

Plant Biology

Biologie végétale

Plant Structure, Growth and Function

Structure, croissance et nutrition des plantes

KEY TERMS AND CONCEPTS

TERMES ET CONCEPTS CLÉS

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

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SC.912.L.14.8

SC.912.L.14.10

SC.912.L.14.53.

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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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Tonicity in Animals

The tonicity of a solution determines if a cell gains or loses water in that solution. The tonicity depends on the permeability of the cell membrane for ...

Tonicity in Plants

Tonicity describes the capacity of a cell to lose or gain water. It depends on the quantity of solute that does not penetrate the membrane. Tonicity ...

Introduction to Membrane Proteins

The cell membrane, or plasma membrane, is an ever-changing landscape. It is described as a fluid mosaic where various macromolecules are embedded in the ...

Facilitated Transport

The chemical and physical properties of plasma membranes cause them to be selectively permeable. Since plasma membranes have both hydrophobic and ...

Primary Active Transport

In contrast to passive transport, active transport involves a substance being moved through membranes in a direction against its concentration or ...

Secondary Active Transport

One example of how cells use the energy contained in electrochemical gradients is demonstrated by glucose transport into cells. The ion vital to this ...

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

Cells pull particles inward and engulf them in spherical vesicles in an energy-requiring process called endocytosis. Phagocytosis (&#x201C;cellular ...

Exocytosis

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

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 ...

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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