Place 2–3 root tips on a watch glass. This is a region of a (semithin) longitudinal section of onion root taken from the meristematic zone; this is the undifferentiated region of plant tissue from which new cells are formed. The two variables for the activity are Phase and Treatment. nl, accessed on 25 March 2022, ) contain 86,073 gene sequence in high confidence (HC) annotation set. Catarrh and a Stuffy Nose. & Schltdl. Symptoms improve from fresh air and a cool room but worsen from cold or damp weather, and warm rooms. Allium cepa bulbs were subjected to four treatments with indigo carmine (0. 5 Gb which is 3. The peel was then placed in a watch glass, which contain water in it. Applied and economic botany for students in technical and agricultural schools, pharmaceutical and medical colleges Onion root tip mitosis refers to a type of cell division where the parent cell produces two identical daughter cells resulting in two diploid daughter cells. (A) Photographs of cells of Allium cepa captured with light microscope (Olympus CX 21) using the 100X objective lens with oil immersion, showing untreated cells in normal division stages and Dec 9, 2012 · Using drop pipette , drop iodine liquid on the cover glass . From this experiment the viewer will be able to see the chromosomes in one stage of meiosis and, during the prophase, metaphase and anaphase stages. Roots of Allium cepa have been treated with a series of concentration 100, 150, 200, 250 and 500µg/ml for Dec 17, 2019 · The extracts of harvested plants were used to grow the root of A. lasiocarpa leaves and stem bark. Keep track of the object (union) layers using microscope. The observations that the bodies in question are frequently located at the surface of the nucleolus and moreover show cytochemical and ultrastructural similarities with this organelle suggest Mitosis in Onion Root Tip (Allium Cepa) Materials. Therefore, it is a region of high cell division. Research regarding cytotoxicity and genotoxicity testing using this type of assay has not yet been carried out for this river. To visualize the onion’s epidermal cells, firm and medium-sized onions are typically chosen. Segments of root tips, 0. The present paper describes the NOR structure of Allium cepa, not only in various cell types but also in the course of mitosis of root tip meristems and discusses possible interpretation of the NOR structure in relation to nucleolar activity. Osmosis is a type of passive transport involving movement of water molecules across a partially permeable membrane. Onion (Allium cepa L. Allium cepa with KMnO4 and Phosphate. The existence of recognizable patterns suggests that an ordered process of chromosome distribution is taking place. e. This research is important to accomplish scientific Jul 2, 2014 · Allium cepa var. 5 SOMATIC MITOSIS IN THE ROOT TIP OF ALLIUM CEPA--A REVIEW AND A REORIENTATION LEON VANDERLYN 1 Biological Abstracts, University of Pennsylvania INTRODUCTION Despite the obvious truism that a proper understanding of somatic mitosis is basic to the whole field of biology, and particularly to Jul 1, 2009 · Higher plants are recognized as excellent genetic models to detect environmental mutagens and are frequently used in monitoring studies. Each row in the dataset is an individual cell observed with a microscope. 1% Tween-20 three times or until the supernatant is clear (centrifuge at 1,500 × g for 3 min). While we produce over 2300 different Botany slides, we also make Jun 22, 2021 · Data on the mitotic index of Allium cepa seedlings exposed to alpha radiation from the source of 241 Am are shown in Table 1. Onion (Allium cepa) is the most routinely used ingredient in Indian cooking and is also one of the commonly cultivated and consumed vegetables globally. 1 mM H 2 O 2 is used to initiate the reaction. Jul 26, 2021 · Cadmium (Cd), one of the most toxic heavy metals, seriously impairs plant and animal physiology and is a potent mutagen. To encourage wider evaluation of onion for physiological Onion (Allium cepa Linn. Onion epidermal cells in all scales are elongated along the onion bulb axis. Onion root tips; 1N HCl; Acetocarmine stain; Glycerine; Watch glass; Slides; cover slip; Procedure. 5 mM. 2010; Qin et al. Exactly 0. Dec 12, 2017 · To prepare walls from onion parenchyma, peel off the abaxial and adaxial side of epidermal layers, and grind the parenchyma to fine powder in liquid nitrogen. 2. The experiment was performed under Jan 9, 2024 · Indigo carmine has a variety of uses in foods, textiles, medicine, pharmaceuticals, and cosmetics. longifolia Download scientific diagram | -Root tip of Allium cepa (longitudinal sections) observed in light microscope. cepa system provides important information to evaluate the clastogenic Nov 6, 2022 · Cellules de l oignons au microscope Jun 1, 2017 · Allium cepa is useful for acute allergy symptoms, especially hay fever with profuse watering of the eyes, and catarrh that irritates and inflames the upper lip and nostrils. 66,882 of these genes are located in 23,661 unplaced scaffolds with a total length of 8. A total chromosome length of 577. 100 g of dried onion sample was dissolved in 1 mL of PBS buffer. cepa. Allium-Mitose03-DM100x BL28. a Cut off 1-2 cm of the root tips. The chromosomes under study are taken from the meristem cells Mar 31, 2016 · in English, Chinese. The. ) is a suitable indicator plant for the determination of potential genotoxic agents in the samples taken from the environment. This test. ) epidermis studied by atomic force microscopy (AFM) and vibrational sum frequency generation (SFG) spectroscopy. Get a microscope slide. 41 MB. Neelkanth M Pujari. Obtain a leaf from a stalk of Elodea and cut the leaf in half. , 2004) [15]. It contains high concentration of folic acid, vitamin B6, magnesium, calcium Jul 1, 2023 · Regarding the suitability of the Allium cepa -based test system, it proved its usefulness as a preliminary tool for evaluating the toxic and genotoxic activities of new molecules prior to their release into the environment. 3. Further, free radical scavenging activity from normal, endoreduplicated and depolyploidized root tips cells was observed to understand the role of phytohormones. Sharing of common germplasm and controlled propagation practices has underpinned research on model plants, such as Arabidopsis and tomato, but not in onion. was used as a bioindicator to observe the effect of water samples from the upstream of the Citarum River on cell and chromosome division. There are studies reporting the toxic potential of indigo carmine on human health and the environment. 01)~\) of the mitotic index was observed for the dose of 80 mGy when compared to the mitotic index of the unirradiated control group, and of the Summary. CA: chromosome agglutination; CF: chromosome fragmentation; BC: binuclear cell Dec 8, 2022 · A healthy Rhoeo leaf from a potted plant is taken. 23 million tons (MT), with China (23. , 2017). Methods Onion epidermal cells were submitted either to an osmotic shock or to a progressive osmotic shift from an osmotic pressure of 2 to 24 MPa to induce Mar 1, 2017 · The importance of Allium cepa test contributes knowledge in preventing toxicity in the environment. (onion) is a good bioindicator for monitoring toxic pollutants in our surroundings. Materials and methods2. Allium cepa-cell nucleus. VI. It showed chromosome damage, which was most pronounced at 100 Jul 15, 2022 · Allium cepa roots were exposed to bisphenol S concentrations of LC50, LC50/2, and LC50/2*3, positive control (MMS, 10 μg/ml), and negative control (distilled water) for 48 h in dark at room temperature. In this study, we investigated the cytogenotoxic effects of indigo carmine using apical root cells of Allium cepa. And in the same time put tissue on the cover glass. Moreover, the A. With the help of forceps the peel was placed on a clean glass slide. 05 lakh hectares and a yield of 224. The aim of the study was to evaluate the Alllium cepa for its pharmacognostical properties and for its hair growth promoting activity Sep 14, 2021 · Review Setting up Your Microscope. A 10% discount applies if you order more than 10 of this item and 15% discount applies if you order more than 25 of this item. pruriens, (II) A. (2008) studied two species of the genus Psychotria, Psychotria leiocarpa Cham. Three different concentrations of sodium sulphate (i. CIL:39065* Cite. Feb 13, 2019 · Trolox, which is used as the antioxidant standard, was prepared in PBS with a concentration of 2. Take a small piece of onion and using tweezers, peel off the membrane from the underside (the rough side). 12 MT), the USA (3. in order to determine the influences of genotoxic substances in, for instance, benzene, naphalen, phenanthren and benzopyren. , 2007). 35 MT) being the top five countries contributing to this total production Preparation. 1. These structures are Feulgen-negative but stain metachromatically with azure B, as the nucleolu … Nov 8, 2000 · Root tip meristem of Allium cepa was used as the material in and observed under a Hitachi-600B transmission electron microscope. Sep 1, 2019 · This study uses the modified Allium cepa assay and an in vitro antioxidant assay to evaluate the toxicity and antioxidant potentials of the aqueous extracts of G. 4. Place the membrane flat on the surface of the slide. In genus Allium, seven species are in cultivation out of 750 species that are known (Yousaf et al. The cellulose microfibril orientation in the abaxial epidermis of onion scales was studied by atomic force microscopy (AFM) and sum frequency generation (SFG) vibrational spectroscopy. Feb 5, 2011 · Although the Allium cepa test has been widely used to identify potentially cytotoxic and genotoxic pollutants in aquatic environments, variable non-standardized choices have been made regarding the number of plant bulbs and roots analyzed. Its association with human cultures is so deeply rooted that pinning research, Allium cepa L. The bulbs should be transferred to petri dish with 30 ml of Alprazolam solution appropriate concentration for the treatments. Phase corresponds to whether the onion cells were observed to be in “Interphase” or “Mitosis” and The onion (Allium cepa L. The total global production of onion is 93. The following 57 files are in this category, out of 57 total. Negative control (A-B) and group exposed to 1000 mg/L TiO 2 NP (C-D). Essay, Pages 3 (630 words) Views. Hence, its observed tissue destruction under microscopic examination, in The Allium test (Levan 1938, 1949) is based on the chromosome study of the meristem cells of the apical root cells of A. The squashed onion root tips were thereafter imaged using a LEICA DM-750 light microscope at 400× and 1000× magnification. Allium cepa root chromosomal aberration assay is widely used to determine May 23, 2023 · First add a few drops of water or solution on the microscope slide to avoid dryness and wilting. The slide containing the stained root tip cells is placed on the stage of the compound microscope, changes taking place are noted and sketched. Mar 3, 2019 · Allium cepa Test. stock photo, images and stock photography. The following 30 files are in this category, out of 30 total. Wash the cell wall pellet with 20 mM HEPES buffer (pH 7. This characteristic provides an introduction to the general anatomy of plant cells and their arrangement. Jan 25, 2017 · Root tip cells of A. Naturally segregated nucleoli have been observed during the prophase in meiocytes of Allium cepa anthers. AFM images showed that cellulose The scope of this paper is to assess the cyto-and genotoxic effects of sulphate on Allium cepa mitosis for root meristem. The observation under the microscope of a cell of an onion skin soaked for 15 minutes The onion (Allium cepa L. 50 g or 0. were treated with different concentrations (0. In this study, the genotoxic effects of H2O2 (Hydrogen Peroxide) and CH2O (Formalin) were determined using Allium cepa root Shalini Tripathi. 0,1%; 1% and 5%) have been used, in which the onion bulbs were immersed for different periods of time such as 6, 24 and 72 hours. 18 Tonnes per hectare (NHRDF 2016- that it brings a thin material which can be observed under the microscope. Cd had cytostatic effect in higher concentration (100 µM). Using a pin, lower the thin glass cover Jan 9, 2018 · Microscope observation of animal and plant cells. Cellulose microfibril orientation in onion (Allium cepa L. 5 µm was observed in the best c-metaphase spread with the longest chromosome being Mar 24, 2014 · The onion plant ( Allium cepa L. The structure of one onion cell had a general rectangular shape with a developed cell wall‚ which gives the rectangular shape to the cell and a cell membrane just beneath it. b Meanwhile, heat 10-25 cm 3 of 1 M hydrochloric acid to 60 °C in a water bath. micronucleus frequency and chromosome aberrations of Allium cepa L Plant species such as Allium cepa L. ) has been used as a food and medicinal crop since ancient times, and it is grown worldwide in 170 countries (FAO, 2018; Petropoulos et al. 0) and 0. The genus Allium, from the Latin for garlic, includes several pungent bulbous plants, commonly called onion. Microscopic observation at 10× magnification of Allium cepa meristematic cells treated with (A) water, (B) methotrexate (standard) and (C) plant extract: (I) M. Each cell with wall, membrane, cytoplasm, nucleus and large vacuole. Plug in the microscope & turn on light source. 1995 Jul 21, 2023 · Advertisements. and Psychotria myriantha Mull. 1. As a matter of fact, observing onion cells through a microscope lens is a staple part of most introductory classes in cell biology - so don’t be surprised if your laboratory reeks of onions during the first week of the semester. 2 genome assembly (www. All of these genes show similarity to the TrEMBL database of protein sequences. During this study the test was carried out by using Allium cepa as an experimental plant and meristematic tissue have been used for analyzing growth in the experimental condition. jpg 2,560 × 1,920; 1. 5%, 1%, 5%, and 10%) of ballast water, and after 48 h the root tips were processed for cytological studies by the aceto-orcein squash pro-cedure. fistulosum and function in the cytoplasm of A. Commercial variety of common onion ( Allium cepa) was used for the determination of different toxicity end points of meristematic cells. Dec 28, 2020 · One of the easiest, simplest, and also fun ways to learn about microscopy is to look at onion cells under a microscope. Blot the HCl with blotting paper and then add 2–3 drops of acetocarmine stain and warm it. The preliminary phytochemical composition of the aqueous extracts was also determined. cepa L. agrogarum L. cepa and A. Add a drop of Iodine solution to the onion skin. The one-layer-cell epidermis of onion scales is commonly used as a model experimental material in botany and molecular biology. Jan 18, 2022 · Onion (Allium cepa) is a high dietary fiber-rich perennial herb that is placed under the family Amaryllidaceae. Oct 5, 2020 · In this activity, we’ll use lab data to test the hypothesis that lectin promotes mitosis in onion roots. Mar 1, 2024 · Subsequently, Allium cepa bulbs were placed in 50 mL Falcon tubes so that only the base of the bulb was immersed in the liquid. 5 1. Description. The root tips were fixed, stained and examined under compound microscope (almost 300–400 dividing cells) to check the extent of chromosomal variations during various stages of mitosis. 252. In 1689 the microscope was found by a scientist named antoni van Dutch nationality. cepa grown in absence and presence of ZnO-NPs were analyzed for chromosomal aberrations under CLS microscope after staining with acridine orange (10 μg/ml). Oct 24, 2017 · Media in category "Microscopic images of Allium cepa". Place a half leaf in each solution. jpg 403 × 444; 37 KB. ) is a challenging subject for experimental studies because of its slow growth, genetic heterogeneity, and sensitivity to environmental and biotic stresses. Download scientific diagram | Anomalies observed in Allium cepa L. The scales of an onion bulb are a modified type of leaf. Equal sized healthy onion bulbs were chosen and the outer scales of bulbs were removed by gently scraping to make the apices of root primodia exposed. Observe the Allium cepa cell with magnification power of microscope. feroniarum hypopus was isolated and purified. The "mooring" strands of the cuticle under the light microscope, are also clearly evident. Allium Species: cepa Family: Amaryllidaceae Life Cycle: Bulb Country Or Region Of Origin: Central Asia Edibility: The bulb and tops are edible raw or cooked. Place 2 drops of dI water on the left and 2 drops 20% salt on the right. The shallot is a botanical variety of the onion which was classified as a separate species until 2010. Focus as desired to obtain a distinct and clear image; Observations and Conclusion. fistulosum was observed in our materials and has been previously reported [ 26 ]. ) is one of the oldest and most widely used vegetable known to Allium is the second largest genus of monocotyledons in the family Amaryllidaceae. " It is a major vegetable crop cultivated in India, with a total area of 14. Lubini et al. Oil immersion objectives, ×40 (numerical aperture 1·00) and ×63 (numerical aperture 1·40) were used for most observations. The onion is the second largest vegetable crop in global production by value, surpassed only by the tomato. Its close relatives include garlic, scallion, leek, and Sep 4, 2016 · The work describes linkage of these two processes with each other under abiotic stress. Add 2 drops of 1N HCl and gently warm it. Although, onion is native to south western part of the Asia, it Mar 31, 2013 · are used to evaluate genotoxicity and micronucleus anal ysis used to verif y mutagenicity of differe nt chemicals. Picture of Onion epidermis with large cells under light microscope. Deepika Gupta. 91 MT), India (19. The chromosomes under study are taken from the meristem cells Sep 26, 2017 · Allium cepa in this study show cell with a complement of sixteen chromosomes. Based on the observations that have been made onthe root squash preparations of onion (Allium cepa L. 0032 Allium cepa L. The final statement is that the cells seen using the microscope is very large but not clear. Allium-Mitose01-DM063x. Feb 1, 2022 · 1. Cytogenetic Effects of Radiation from Projector on Meristematic Cells of Allium Cepa…. ) is a bulbous, biennial herb known as the "Queen of the Kitchen. Oct 14, 2009 · The aim of this work is to study cytoplasmic vesicle formation in onion epidermal cells (Allium cepa) as a function of the kinetics of osmotic pressure variation in the external medium. Methods: The samples were collected in a mushroom cultivation base, and the H. During interphase the cell grows, makes a copy of its DNA and prepares to divide into two cells. The genotoxic level of the agent under study is reflected by structural changes of the chromosomes and their changed numbers. ) have undergone mitosis The importance of Allium cepa test contributes knowledge in preventing toxicity in the environment. Cells represent the make up of our being as well as many other organisms whether they are unicellular or multicultural. Image 74358489. Cells can also be complex or quite simplistic in design and contents, depending on the purpose of its function Media in category "Microscopic images of mitoses in Allium cepa root meristem". jpg 2,288 × 1,907; 816 KB. Clear epidermal cells of an onion, Allium cepa, in a single layer. cepa following its standard method. 2013). Root hairs are tubular extensions from the root surface that expand by tip growth. 42 MT), Egypt (3. J Cell Biol 1965; 26 :1–17. This could be confirmed by observation of living cells using phase contrast and other illumination techniques. A part of the peel was removed with the help of forceps from the lower surface of the leaf. Triarch Incorporated offers superior prepared microscope slides. Effect of a cadmium salt on chromosome integrity was studied for increasing concentrations and for different exposure time in root tips of onion A. The mitotic Sep 10, 2021 · Water will flow out of the Elodea cells by osmosis, shrinking the cell membrane away from the stiff cell wall (plasmolysis). 05),\) a significant increase (\(p < 0. wur. 0 mm long, were excised for both TEM and SEM preparations. L'observation est réalisée à un grossissement x400 après coloration à l'orcéine Mar 4, 2019 · Based on this observation, we conclude that this part of the A. Bulbs of Allium cepa were obtained from commercial sources. Spontaneous chromosome doubling in interspecific hybrids between A. cepa as a test system to detect mutagens dates 20-252 Allium Cepa Prepared Microscope Slide Allium cepa (onion, liliaceae); fruit, cs. cepa, which is a biologically useful plant for experimental observation (Qin et al. Based on the principle of work, the microscope can be divided into two parts, namely optical and electron microscopy. May 31, 2019 · Abstract. A. Introduction. Topics: Plants. When observing the epidermal cell of an onion bulb under a microscope, it appears simple and transparent. meristematic cells under light microscope (x400). 739 ALEGE, GO; OJO, BH; EFENJI GI; KACHI JB; TAWOSE, FO; GLEN, E; OLADIMEJI, EO Chromosome Observation: The prepared slides were then observed under the light microscope at 4X, 10X, 40X, and 100X objectives. 03 MT) and Iran (2. The majority of the innumerable pits present in the younger cell are below the range of visibility under the light microscope. For the control group, Allium cepa bulbs were immersed in ultrapure water. Rotate the objectives so that the lowest power objective (smallest in size) clicks into place. Allium cepa is also known as the “garden onion” or “bulb” onion, related to wild species found in Central Asia. Dec 28, 2013 · Adequate root growth should be obtained in 3-4 days. Observe and study mitosis by placing the slide under the compound microscope. We use group of 6 bulbs of Allium cepa for each treatment. This test widely used in determining genotoxic and cytotoxic substances found in the water system. For each concentration of indigo carmine and the control group, three bulbs of Allium cepa were used. . Among the plant species, Alium cepa has been used to evaluate DNA damages, such as chromosome aberrations and disturbances in the mitotic cycle. oniongenome. Bulbs with roots of Allium cepa L. (2n = 16) is one variation of A. However, the plant also has poisonous characteristics as noted in the "Poisonous to Humans" section of this record. Pick up microscope by carrying arm, position it so it is accessible to your seat, with open side of the stage facing you. Objective: To observe the external morphology of Histiostoma feroniarum hypopus under a light microscope. This highly focused type of cell expansion, combined with position of root hairs on the surface of the root, makes them ideal cells for microscopic observation. Nov 22, 2021 · Onions ( Allium cepa) have featured in many scientists’ first attempts at using a microscope, as well as in a variety of dishes and medicinal uses around the world. test. . Please use this to reference an image. The slide samples were prepared and observed under an optical microscope. Based on statistical analysis using one-way ANOVA followed by the Tukey test (\(p < 0. Dec 1, 2018 · Bulb onion (Allium cepa L. Employing the A. The onion plant (Allium cepa L. cepa is characterized as low cost, convenient storage and handling, short test time, numerous of roots and large cells with excellent chromosome conditions (Liu et al. 0 mm Segments of root tips, 0. Maintenance of the microscope is very important, because the microscope is very useful for observation and research in human life. cepa genome can be replaced by A. Photo. All concentrations induced a number of chromosomal aberrations in the root tip cells. Because of its peculiar taste, unique flavor, highly valued aroma, and various health benefits, it is sometimes referred to as the “Queen of the kitchen” (Griffiths et al The plant test system of Allium cepa is as an ideal bioindicator for the first screening of genotoxicity, helping with studies that prevent damages to human health (Bagatini et al. Mar 9, 2021 · PDF | On Mar 9, 2021, Rinsa S R published Investigation of nuclear structural variations under chronic stress conditions in Allium cepa using LSFM | Find, read and cite all the research you need Oct 14, 2009 · A confocal laser scanning system, the Leica TCS 4D microscope (Leica, Wetzlar, Germany), equipped with an argon and krypton laser and epifluorescence attachments (excitation 488 nm, emission PB-FITC) was used. Endoreduplicated root tip cells of Allium cepa were depolyploidized by exogenous phytohormones. MATERIALS AND METHODS. Under the light microscope the nucleolus is seen to consist of two clearly differentiated regions: a central core, which is strongly argyrophilic (ochre or dark brown) and slightly basophilic, surrounded by a basophilic peripheral The observation showed a large number of onion cells. 27 lakh tonnes with the productivity of 17. , from Latin cepa meaning "onion"), also known as the bulb onion or common onion, is a vegetable that is the most widely cultivated species of the genus Allium. Bulbs from the onion family have been a source of food for millennia. Interphase, preprophase, and prophase nuclei of meristematic cells of Allium cepa, Vicia faba, and Raphanus sativus are characterized by the presence of spherical bodies approximately 1 micro in diameter. Roots Sep 10, 2022 · Allium cepa v1. Download. In the course of an earlier electron microscope study (1) of nuclear structures in meristematic cells of Allium cepa and Vicia faba, spherical bodies, approximately 2 /z in diameter, were observed at interphase. c Wash the root tips in cold water for 4-5 minutes and dry on filter paper. The use of a light microscope places limits on the resolution of images seen. Arg. Put in a small volume of ethanoic acid on a watchglass (or other shallow dish) for 10 minutes. ) is widely planted worldwide as a valuable vegetable crop. Article CAS Google Scholar Moreover, in Allium cepa, these spherules often exhibit dense particles which are also found within the fibrillar zones of the nucleolus in this species. widely used in determining genotoxic and cytoto xic substances found in the water Mar 1, 2001 · A light and electron microscope study of small, spherical bodies in meristematic cells of Allium cepa, Vicia faba and Raphanus sativus. We propose numbers for bulbs and roots per bulb when comparing the frequencies of micronuclei, mitotic anomalies and mitotic index with this test. Traces of onion remains along with fig and date Observing Plasmolysis in Onion Cells (Allium cepa) Plasmolysis is the process in plant cells in which the cytoplasm is separated from the cell wall as a result of water loss through osmosis. Lastly the slide was observed under the microscope. These structures were lighter than either the chromosomes or the nucleolus under Dec 3, 2013 · Cellulose microfibril orientation in plant cell walls changes during cell expansion and development. jpg 859 × 942; 420 KB. Photomicrographs of Dec 30, 2016 · The onion (Allium cepa L. This chapter describes the method that is routinely used in our laboratory for live cell Download scientific diagram | Champs d'observation au niveau d'un méristème racinaire chez Allium cepa. Roots were cut and then fixed by Carnoy fixative solution which consists of ethanol and glacial acetic acid (3:1, v/v) at 4 °C for 24 h. The standard curve was prepared by diluting the Trolox solutions. Feb 22, 2021 · About Press Copyright Contact us Creators Advertise Developers Terms Privacy Policy & Safety How YouTube works Test new features NFL Sunday Ticket Press Copyright The material used in this study was the root tip meristems of Allium cepa. tq yb nw gy lw la gx hl hx je