Name: how phloem moves sugars in plants
Uploaded: 2026-08-26T08:21:05.159Z
Duration: 2 min 10 s
Channel: JoVE

K12 Standards

Florida Department of Education

High School

Life Science

SC.912.L.14

SC.912.L.14.7

Phloem and Sugar Transport

A fotoss&#xED;ntese gera a&#xE7;&#xFA;car em folhas de plantas. No entanto, o a&#xE7;&#xFA;car &#xE9; frequentemente necess&#xE1;rio em partes distantes da planta. A transloca&#xE7;&#xE3;o &#xE9; o processo que distribui os produtos da fotoss&#xED;ntese para outros tecidos de planta.As folhas s&#xE3;o tipicamente chamadas fontes de a&#xE7;&#xFA;car, que s&#xE3;o locais que produzem m ais a&#xE7;&#xFA;car do que consomem. Em contraste, as ra&#xED;zes, os caules e os frutos s&#xE3;o normalmente consumidores de a&#xE7;&#xFA;car, chamados sumidouros de a&#xE7;&#xFA;car. O transporte de a&#xE7;&#xFA;car entre a fonte e o sumidouro ocorre no tecido vegetal chamado floema.Em angiospermas, o floema &#xE9; composto por c&#xE9;lulas especializadas chamados de elementos de Tubo Crivado, arranjados de ponta a ponta para criar longos tubos. As c&#xE9;lulas de Companhia est&#xE3;o localizadas ao lado cada elemento de Tubo Crivado. O a&#xE7;&#xFA;car pode chegar ao floema por v&#xE1;rias rotas.Pode viajar atrav&#xE9;s do espa&#xE7;o celular e das paredes extracelulares atrav&#xE9;s de poros que ligam diretamente ao citoplasma de c&#xE9;lulas vizinhas. Uma solu&#xE7;&#xE3;o aquosa, chamada de seiva de floema, composta de a&#xE7;&#xFA;car, amino&#xE1;cidos, hormonas e minerais, flui atrav&#xE9;s dos elementos do Tubo Crivado. De acordo com a hip&#xF3;tese do fluxo de press&#xE3;o, A &#xE1;gua segue o a&#xE7;&#xFA;car pelo floema por osmose, aumentando a press&#xE3;o&#xA0;dentro do floema e assim impulsionando o movimento da seiva do floema.A seiva do floema ent&#xE3;o flui para o tecido de drenagem mais pr&#xF3;ximo, que tem uma baixa concentra&#xE7;&#xE3;o de a&#xE7;&#xFA;car. O a&#xE7;&#xFA;car se difunde ou &#xE9; ativamente transportado para fora do floema. Como o a&#xE7;&#xFA;car &#xE9; descarregado, a &#xE1;gua segue por osmose e alivia press&#xE3;o dentro do floema.Utilizando&#xA0;a transloca&#xE7;&#xE3;o atrav&#xE9;s do floema, as plantas podem distribuir recursos para os tecidos em que eles s&#xE3;o necess&#xE1;rios em um determinado momento ou esta&#xE7;&#xE3;o.

Heo JO, Roszak P, Furuta KM, Helariutta Y. Desenvolvimento do floema: conhecimento atual e perspectivas futuras. Am J Bot. Setembro de 2014; 101(9):1393-402. [<a href="https://www.ncbi.nlm.nih.gov/pubmed/25253700" target="_blank">Fonte</a>]

Liesche J, Patrick J. Uma atualização sobre o transporte de floema: um fluxo a granel simples sob regulamentação complexa. F1000Res. 6 de dezembro de 2017;6:2096. [<a href="https://www.ncbi.nlm.nih.gov/pubmed/29259777" target="_blank">Fonte</a>]

floema e transporte de açúcar

Assim como muitos organismos vivos, as plantas possuem tecidos especializados em fun&#xE7;&#xF5;es vegetais espec&#xED;ficas. Por exemplo, os sistemas caulinares s&#xE3;o bem adaptados ao crescimento r&#xE1;pido, enquanto as ra&#xED;zes s&#xE3;o estruturadas para adquirir recursos com efici&#xEA;ncia. No entanto, a produ&#xE7;&#xE3;o de a&#xE7;&#xFA;car est&#xE1; restrita principalmente aos tecidos fotossint&#xE9;ticos localizados nas folhas das plantas angiospermas. O a&#xE7;&#xFA;car e outros recursos s&#xE3;o transportados das c&#xE9;lulas fotossint&#xE9;ticas para outros tecidos especializados por um processo chamado transloca&#xE7;&#xE3;o.
Em uma planta, os tecidos que produzem mais a&#xE7;&#xFA;car do que consomem s&#xE3;o fontes de a&#xE7;&#xFA;car &#x2014; as folhas s&#xE3;o o principal exemplo disso. Ra&#xED;zes, sistemas caulinares, flores e frutos s&#xE3;o geralmente considerados drenos de a&#xE7;&#xFA;car, pois necessitam de mais a&#xE7;&#xFA;car do que conseguem produzir. A transloca&#xE7;&#xE3;o distribui a&#xE7;&#xFA;car, horm&#xF4;nios, amino&#xE1;cidos e algumas mol&#xE9;culas sinalizadoras das fontes de a&#xE7;&#xFA;car para os drenos de a&#xE7;&#xFA;car por meio de uma estrutura semelhante a um tubo nas plantas vasculares, chamada floema. O fluxo pode ser bidirecional no floema, que &#xE9; composto por c&#xE9;lulas unidas de ponta a ponta por placas crivadas, formando os elementos de tubo crivado. Essas c&#xE9;lulas apresentam paredes celulares espessadas, que lhes conferem suporte mec&#xE2;nico, e s&#xE3;o acompanhadas por c&#xE9;lulas-companheiras vizinhas, que favorecem a manuten&#xE7;&#xE3;o do floema e o carregamento de solu&#xE7;&#xF5;es no floema a partir dos tecidos circundantes.
O carregamento do floema pode ocorrer pela via apopl&#xE1;stica ou pela rota simpl&#xE1;stica e pode ser passivo ou ativo. Essas vias at&#xE9; o floema podem atuar simultaneamente ou em sequ&#xEA;ncia, e h&#xE1; algumas evid&#xEA;ncias de que as plantas podem alternar entre modos de carregamento dependendo das demandas de &#xE1;gua e energia da planta. Em muitos casos, o simportador de sacarose/H+ acopla o carregamento de sacarose no floema ao transporte de um &#xED;on de hidrog&#xEA;nio.
De acordo com a hip&#xF3;tese do fluxo de press&#xE3;o, o gradiente de concentra&#xE7;&#xE3;o de a&#xE7;&#xFA;car promove o fluxo de &#xE1;gua para o floema, resultando na gera&#xE7;&#xE3;o de press&#xE3;o. Como resultado, a seiva do floema se desloca em dire&#xE7;&#xE3;o &#xE0;s &#xE1;reas de menor press&#xE3;o, no dreno de a&#xE7;&#xFA;car mais pr&#xF3;ximo. No dreno de a&#xE7;&#xFA;car, a sacarose &#xE9; transportada para a &#xE1;rea de menor concentra&#xE7;&#xE3;o de a&#xE7;&#xFA;car, impulsionando seu movimento para fora do floema. A &#xE1;gua acompanha a sacarose, aliviando a press&#xE3;o no floema.

Floema e transporte de açúcar

Like many living organisms, plants have tissues that specialize in specific plant functions. For example, shoots are well adapted to rapid growth, while ...

https://cloudfront.jove.com/files/ftp_upload/11101/11101_article_thumb_11101.jpg

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

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 pathway is a tube-like part of the vascular system called phloem. Flow in the phloem can move in both directions, depending on where the plant needs resources.

Phloem is built from sieve-tube elements that are joined end to end by plasmodesmata. These cells have thickened cell walls, which help support the tissue. Companion cells sit next to them and help keep the phloem healthy. They also help load solutions into the phloem from nearby tissues.

Phloem loading can happen through the apoplastic route or the symplastic route. It may be passive or active. These pathways can work at the same time or one after the other. Some evidence suggests that plants can switch loading modes based on water needs and energy demands. In many cases, a sucrose/H+ symporter helps move sucrose into the phloem together with a hydrogen ion.

The pressure-flow hypothesis explains how sap moves through phloem. As sugar builds up, water moves into the phloem by osmosis and creates pressure. The sap then flows toward the nearest sugar sink, where pressure is lower. At the sink, sucrose moves out into the area with lower sugar concentration. Water follows the sucrose, and pressure in the phloem is reduced.

How Phloem Moves Sugars in Plants

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

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

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

the soil ecosystem

Soil Layers and How Soil Forms

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

key elements for plant nutrition

Plant Nutrients: Macro and Micro Needs

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

the roles of bacteria and fungi in plant nutrition

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

How Soil Microbes Help Plants Get Nutrients

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

epiphytes, parasites, and carnivores

Plant Nutritional Adaptations in Nature

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

the apoplast and symplast

Plant Water Transport Pathways

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

key terms and concepts

Learn how phloem carries sugar, hormones, and amino acids from leaves to sink tissues using sieve tubes, companion cells, and pressure-flow transport.

How Phloem Moves Sugars in Plants | 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.

new-york-state-science-learning-standards

New York State Science Learning Standards

Structure and Function

HS-LS1-2.

Georgia Standards of Excellence

9-12

Botany

SBO1.

Transport

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, ...

Characteristics of Life

Biology is a natural science that studies life and living organisms, including their structure, function, development, interactions, evolution, ...

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

Animal and Plant Cell Structure

Animal and plant cells not only differ in their structure, function, and mode of nutrition but also in how they reproduce, specialize, and organize into ...

Eukaryotic Evolution

The endosymbiont theory is the most widely accepted theory of eukaryotic evolution; however, its progression is still somewhat debated. According to the ...

Cell Diversity

The concept of a cell started with microscopic observations of dead cork tissue by Robert Hooke in 1665. Hooke coined the term &#34;cell&#34; based on the ...

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

Cell sizes vary widely among and within organisms. Bacterial cells range between 1-10 micrometers (&#x3BC;m)and are considerably smaller than most ...

Eukaryotic Compartmentalization

One of the distinguishing features of eukaryotic cells is that they contain membrane-bound organelles, such as the nucleus and mitochondria, that carry ...

Prokaryotic Cells

Prokaryotes are small unicellular organisms that include the domains&#x2014;Archaea and Bacteria. Bacteria include many common organisms, such as ...

Cytoplasm

The cytoplasm consists of organelles and a framework of protein scaffolds called the cytoskeleton suspended in an aqueous solution, the cytosol. The ...

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

Endoplasmic ReticulumThe endoplasmic reticulum (ER) is an extensive network of membranous sacs and tubules in eukaryotic cells, continuous with the outer ...

Ribosomes

Ribosomes translate genetic information encoded by messenger RNA (mRNA) into proteins. Both prokaryotic and eukaryotic cells have ribosomes. Cells that ...

Golgi Apparatus

As they leave the Endoplasmic Reticulum (ER), properly folded and assembled proteins are selectively packaged into vesicles. These vesicles are ...

Microtubules

There are three types of cytoskeletal structures in eukaryotic cells&#x2014;microfilaments, intermediate filaments, and microtubules. With a diameter of ...

Peroxisomes

Peroxisomes and mitochondria are two important oxygen-utilizing organelles in eukaryotic cells. Mitochondria carry out cellular respiration&#x2014;the ...

Gap Junctions

Multicellular organisms employ a variety of ways for cells to communicate with each other. Gap junctions are specialized proteins that form pores between ...

The Extracellular Matrix

In order to maintain tissue organization, many animal cells are surrounded by structural molecules that make up the extracellular matrix (ECM). Together, ...

Tissues

Cells with similar structure and function are grouped into tissues. A group of tissues with a specialized function is called an organ. There are four main ...

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

The organs in a multicellular organism&#x2019;s body are made up of tissues formed by cells. To work together cohesively, cells must communicate. One way ...

What are Membranes?

A key characteristic of life is the ability to separate the external environment from the internal space. To do this, cells have evolved semi-permeable ...

Membrane Fluidity

Cell membranes are composed of phospholipids, proteins, and carbohydrates loosely attached to one another through chemical interactions. Molecules are ...

Fluid Mosaic Model

The fluid mosaic model was first proposed as a visual representation of research observations. The model comprises the composition and dynamics of ...

What is an Electrochemical Gradient?

Adenosine triphosphate, or ATP, is considered the primary energy source in cells. However, energy can also be stored in the electrochemical gradient of an ...

Diffusion

Diffusion is the passive movement of substances down their concentration gradients&#x2014;requiring no expenditure of cellular energy. Substances, such as ...

Osmosis

Approximately 60% to 95% of the weight of living organisms is attributed to water. Therefore, maintaining appropriate water balance within cells is of ...

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 ...

Overview of Electron Microscopy

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

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

Phase Contrast and Differential Interference Contrast Microscopy

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

Confocal Fluorescence Microscopy

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

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

SC.912.L.14.4

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

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

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

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

How Phloem Moves Sugars in Plants

Description

Transcript

Tags

More videos by Standards