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Sea Urchin Fertilization
 
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This 3D animation describe the sea urchin fertilization at cell biology level.
Views: 100955 Lei Jin
Baby sea urchin's first cell division
 
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This video was taken by fellows at the Marine Biological Laboratory Science Journalism Fellowship. The fellows fertilized sea urchin eggs, and made beautiful videos and photos of cells dividing and growing in the earliest stages of life. See the rest at http://boingboing.net/2012/07/02/the-beginning-of-life.html
Views: 3583 Maggie Koerth-Baker
Sperm Cell Toxicity Tests Using the Sea Urchin EPA VIDEO
 
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“Sperm Cell Toxicity Tests Using the Sea Urchin, Arbacia punctulata” (EPA, 2009). The methods illustrated in the video and described in this supplemental guide support the methods published in the U.S. Environmental Protection Agency’s (EPA’s) Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Marine and Estuarine Organisms, Third Edition (EPA, 2002a), referred to as the Saltwater Chronic Methods Manual. The video and this guide provide details on preparing for and conducting the test based on the expertise of personnel at the following EPA Office of Research and Development (ORD) laboratories: National Health and Environmental Effects Research Laboratory (NHEERL) – Atlantic Ecology Division in Narragansett, Rhode Island NHEERL – Gulf Ecology Division in Gulf Breeze, Florida National Exposure Research Lab (NERL) – Ecological Exposure Research Division (EERD) in Cincinnati, Ohio This guide and its accompanying video are part of a series of training videos produced by EPA’s Office of Wastewater Management. This Saltwater Series includes the following videos and guides: “Mysid (Americamysis bahia) Survival, Growth, and Fecundity Toxicity Tests” “Culturing Americamysis bahia” “Sperm Cell Toxicity Tests Using the Sea Urchin, Arbacia punctulata” “Red Algal (Champia parvula) Sexual Reproduction Toxicity Tests” “Sheepshead Minnow (Cyprinodon variegatus) and Inland Silverside (Menidia beryllina) Larval Survival and Growth Toxicity Tests” The Freshwater Series, released in 2006, includes the following videos and guides: “Ceriodaphnia Survival and Reproduction Toxicity Tests” “Culturing of Fathead Minnows (Pimephales promelas)” “Fathead Minnow (Pimephales promelas) Larval Survival and Growth Toxicity Tests” All of these videos are available through the National Service Center for Environmental Publications (NSCEP) at 800 490-9198 or [email protected]
Views: 812 Gustavo Pesce
How to get sperm and eggs from a sea urchin
 
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Explanation on how to get eggs and sperm from the sea urchins.
Views: 16869 The Lucky Urchin
Sea Urchin Cell Division Lab
 
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A lab conducted by students on the division of sea urchin cells immediately after fertilization. All of the sources used are cited at the end of the video.
Views: 1305 Ally McDonough
Sea urchin gastrulation
 
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Podcast for students of Zoology 470, UW-Madison, on sea urchin gastrulation. Some images courtesy of Gilbert, Developmental Biology, 10e (Sinauer).
Views: 5808 Jeff Hardin
08 06SeaUrchinTimeLapse SV
 
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Sea Urchin Embryonic Development (time lapse) Video This series of video clips shows selected important events in sea urchin embryonic development. 1) The unfertilized egg is about 100 micrometers (µm) in diameter, similar to that of humans, and is surrounded by an extracellular layer called the vitelline layer. Upon fertilization by the first sperm, the vitelline layer becomes raised off the surface of the egg and hardens, forming the protective structure known as the fertilization envelope. All cleavages up to the blastula stage occur within this envelope. 2) During first cleavage, the nuclear envelope breaks down, and the duplicated chromosomes separate into two complete sets, followed by cytokinesis. In the two new cells, or blastomeres, you can clearly see the two new nuclei. 3) Second cleavage, progressing from 2 to 4 cells, is seen here. Cleavages will proceed synchronously, approximately every 30 minutes, passing through the morula stage (16-64 cells) when the cells are loosely attached to each other, up to the blastula stage (more than 128 cells). 4) The blastula stage is seen at the end of this clip. This stage is made up of a hollow ball of 1000 or so cells, arranged in a single-layered epithelium. The cells are tightly packed together, maintaining a space in the center called the blastocoel cavity. 5) At the beginning of gastrulation, a number of cells in the flattened "vegetal pole," shown here at the bottom of the embryo, move as individual cells into the blastocoel cavity. In this cavity the cells migrate around, fuse with each other in a ring, and begin secreting elements of the calcium carbonate skeleton of the embryo. Because these cells are the first to move as individual cells in the embryo, they are called the primary mesenchyme cells (PMCs). The remaining cells in the vegetal pole fill in the gaps, restoring a complete epithelial sheet. 6) While the PMCs are migrating around, archenteron formation, or formation of the embryonic digestive tract, begins. The first stage involves the pushing in of the vegetal pole to form a short, wide, blind-ended tube. 7) This tube then narrows and elongates by a process that includes extensive cell rearrangement. Following this elongation, a subset of cells (secondary mesenchyme cells) at the tip of the archenteron will extend processes that contact a specific site on the inside of the ectodermal wall and tow the archenteron toward that spot. The wall of the ectoderm will bend inward and fuse with the tip of the archenteron to form the mouth. The digestive tract will differentiate into an esophagus, a stomach, and an intestine, and the embryo will begin to feed. Four to 8 or 12 arms will extend, supported by internal skeletal elements. This feeding larva will float around in the plankton, eating algal cells, for 5 or 6 weeks, then will metamorphose into the adult form of the sea urchin. Credit: Rachel Fink, editor, "A Dozen Eggs," Society for Developmental Biology
Views: 21349 Chandra Brown
When the egg meets sperm
 
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PLEASE, subscribe! I have other exciting videos! A exciting story from sea urchin life. I added the sperm at 27 sec, and at 59 sec the envelope already started to form! Isn't that fantastic? This is the "real close-up" porn - under the microscope! Fertilization of the sea urchins happen externally and the lifecycle is fast and predictable. Оплодотворение яйцеклетки морского ежа. Сперматозоиды добавлены на 27-й секунде. 受精 私は27秒で精子を追加しました
Views: 3844918 The Lucky Urchin
Developmental biology part 4 : sea urchin fertilization
 
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For more information, log on to- http://shomusbiology.weebly.com/ Download the study materials here- http://shomusbiology.weebly.com/bio-materials.html Fertilisation (also known as conception, fecundation and syngamy) is the fusion of gametes to initiate the development of a new individual organism.[1] In animals, the process involves the fusion of an ovum with a sperm, which eventually leads to the development of an embryo. Depending on the animal species, the process can occur within the body of the female in internal fertilisation, or outside (external fertilisation). The cycle of fertilisation and development of new individuals is called reproduction. Sperm find the eggs via chemotaxis, a type of ligand/receptor interaction. Resact is a 14 amino acid peptide purified from the jelly coat of A. punctulata that attracts the migration of sperm. After finding the egg, the sperm penetrates the jelly coat through a process called sperm activation. In another ligand/receptor interaction, an oligosaccharide component of the egg binds and activates a receptor on the sperm and causes the acrosomal reaction. The acrosomal vesicles of the sperm fuse with the plasma membrane and are released. In this process, molecules bound to the acrosomal vesicle membrane, such as bindin, are exposed on the surface of the sperm. These contents digest the jelly coat and eventually the vitelline membrane. In addition to the release of acrosomal vesicles, there is explosive polymerisation of actin to form a thin spike at the head of the sperm called the acrosomal process. The sperm binds to the egg through another ligand reaction between receptors on the vitelline membrane. The sperm surface protein bindin, binds to a receptor on the vitelline membrane identified as EBR1. Fusion of the plasma membranes of the sperm and egg are likely mediated by bindin. At the site of contact, fusion causes the formation of a fertilisation cone. Source of the article published in description is Wikipedia. I am sharing their material. Copyright by original content developers of Wikipedia. Link- http://en.wikipedia.org/wiki/Main_Page
Views: 57992 Shomu's Biology
Sea Urchin Fertilization
 
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Views: 29039 bluedoorlabs
Sea Urchin Invagination
 
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Views: 1206 UVUProfessor
The Miracle of Fertilization
 
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A detailed explanation of the process of fertilization (sea urchin eggs and sea urchin sperm). This is the "real close-up" porn!
Views: 50686 The Lucky Urchin
Sea urchin axis specification
 
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Podcast on sea urchin axis specification for students of Zoology 470, UW-Madison
Views: 1116 Jeff Hardin
Developing Sea Urchins
 
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Blastula, Early and Mid gastrula of S. purpuratus (sea urchin)
Views: 2822 MsDCaba
Sea urchin fertilization calcium wave
 
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Here, five unfertilized sea urchin eggs have been microinjected with a calcium indicator (and a tiny oil droplet to mark injected eggs). Sperm binding to the egg initiates a signaling cascade that results in the release of calcium from intracellular stores. Calcium release begins at the point of sperm contact and propagates through the cell as a wave. One of the consequences of calcium release is exocytosis of cortical granules and elevation of the fertilization envelope. Eventually, calcium is reabsorbed back into intracellular stores.
Views: 26833 Mariana Leguia
Sea Urchin Embryo, Individual Cell
 
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Sea urchin embryo at blastula stage comport a peripheral epithelium of individually ciliated cells. Each cell possesses one cilium, difficult to visualize because of interference of neighbour cilia. At high magnification, the low depth of field of the 100X objective allows indivisualization of cilium and detailed record of its beating. The last part of the clip shows individual cell that can be detached experimentally.
Views: 67 jacosson
Sea Urchin Life
 
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This video describes the life of a sea urchin. Using some original experimental data and images borrowed from a variety of sources, we hoped to discuss the anatomy, life cycle (including reproduction), and typical behavior of sea urchins. A list of sources references and images utilized are listed below: Cameron, R. A., Samanta, M., Yuan, A., He, D., & Davidson, E. (2008, November 14). Abstract. National Center for Biotechnology Information. Retrieved March 15, 2013, from http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2686435/ Fertilization - Introduction. (n.d.). Fertilization in Sea Urchins. Retrieved March 15, 2013, from http://worms.zoology.wisc.edu/urchins/SUfert_intro.html Fertilization: Avoiding Polyspermy. (n.d.). Developmental Biology Interactive. Retrieved March 15, 2013, from http://www.devbio.biology.gatech.edu/?page_id=519 Introduction to the Deuterostomia. (n.d.). Introduction to the Deuterostomia. Retrieved March 15, 2013, from http://www.ucmp.berkeley.edu/phyla/deuterostomia.html Runft, L. L., Jaffe, L. A., & Mehlmann, L. M. (n.d.). Egg Activation at Fertilization: Where it all Begins. Uchc.edu. Retrieved March 16, 2013, from http://cell.uchc.edu/pdf/mehlmann/sdarticlerunft.pdf Sea Urchin Fertilization. (2009, April 20). YouTube. Retrieved March 15, 2013, from http://www.youtube.com/watch?v=jp-RgIRgcYE Sea urchin fertilization. (2009, October 30). YouTube. Retrieved March 18, 2013, from http://www.youtube.com/watch?v=T6BtSMerBmw Sea Urchin Genome Project. (n.d.). Sea Urchin Genome Project. Retrieved March 15, 2013, from http://sugp.caltech.edu/SUGP/ Sea Urchins Divide! (2008, September 05). YouTube. Retrieved March 17, 2013, from http://www.youtube.com/watch?v=H0zL4O45eOU Sea Urchins. (n.d.). Sea Urchins. Retrieved March 14, 2013, from http://academics.smcvt.edu/dfacey/aquaticbiology/coastal pages/sea urchins.html SUE - ANATOMY & PHYSIOLOGY. (n.d.). SUE - ANATOMY & PHYSIOLOGY. Retrieved March 14, 2013, from http://www.stanford.edu/group/Urchin/anaphys.html  . (n.d.). SUE. Retrieved March 16, 2013, from http://www.stanford.edu/group/Urchin/gametes.htm
Views: 4615 Sharadram Sundaresan
Sea urchin development
 
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This developmental biology lecture explains about the sea urchin development including the sea urchin fertilization, prevention of polyspermy and the blastula and gastrulation of sea urchin embryo to produce the adult sea urchin animal. For more information, log on to- http://www.shomusbiology.com/ Get Shomu's Biology DVD set here- http://www.shomusbiology.com/dvd-store/ Download the study materials here- http://shomusbiology.com/bio-materials.html Remember Shomu’s Biology is created to spread the knowledge of life science and biology by sharing all this free biology lectures video and animation presented by Suman Bhattacharjee in YouTube. All these tutorials are brought to you for free. Please subscribe to our channel so that we can grow together. You can check for any of the following services from Shomu’s Biology- Buy Shomu’s Biology lecture DVD set- www.shomusbiology.com/dvd-store Shomu’s Biology assignment services – www.shomusbiology.com/assignment -help Join Online coaching for CSIR NET exam – www.shomusbiology.com/net-coaching We are social. Find us on different sites here- Our Website – www.shomusbiology.com Facebook page- https://www.facebook.com/ShomusBiology/ Twitter - https://twitter.com/shomusbiology SlideShare- www.slideshare.net/shomusbiology Google plus- https://plus.google.com/113648584982732129198 LinkedIn - https://www.linkedin.com/in/suman-bhattacharjee-2a051661 Youtube- https://www.youtube.com/user/TheFunsuman Thank you for watching
Views: 15894 Shomu's Biology
Sea urchin embryo
 
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This video was taken by fellows at the Marine Biological Laboratory Science Journalism Fellowship. The fellows fertilized sea urchin eggs, and made beautiful videos and photos of cells dividing and growing in the earliest stages of life. See the rest at http://boingboing.net/2012/07/02/the-beginning-of-life.html
Views: 1671 Maggie Koerth-Baker
Spines of a sea urchin (magnified)
 
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This video was taken by fellows at the Marine Biological Laboratory Science Journalism Fellowship. The fellows fertilized sea urchin eggs, and made beautiful videos and photos of cells dividing and growing in the earliest stages of life. See the rest at http://boingboing.net/2012/07/02/the-beginning-of-life.html
Views: 2709 Maggie Koerth-Baker
First cleavage of fertilized sea urchin egg cells by MBL Science Journalism Fellows
 
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First cleavage of fertilized sea urchin egg cells. Credit: MBL Logan Science Journalism Fellows.
Views: 1100 MBL Woods Hole
Lecture 5 Sea Urchins
 
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Views: 656 UVUProfessor
Perturbation of gut bacteria induces a coordinated cellular immune response in the purple sea urchin
 
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Perturbation of gut bacteria induces a coordinated cellular immune response in the purple sea urchin larva. Eric CH Ho et al (2016), Immunology and Cell Biology http://dx.doi.org/10.1038/icb.2016.51 The purple sea urchin (Strongylocentrotus purpuratus) genome sequence contains a complex repertoire of genes encoding innate immune recognition proteins and homologs of important vertebrate immune regulatory factors. To characterize how this immune system is deployed within an experimentally tractable, intact animal, we investigate the immune capability of the larval stage. Sea urchin embryos and larvae are morphologically simple and transparent, providing an organism-wide model to view immune response at cellular resolution. Here we present evidence for immune function in five mesenchymal cell types based on morphology, behavior and gene expression. Two cell types are phagocytic; the others interact at sites of microbial detection or injury. We characterize immune-associated gene markers for three cell types, including a perforin-like molecule, a scavenger receptor, a complement-like thioester-containing protein and the echinoderm-specific immune response factor 185/333. We elicit larval immune responses by (1) bacterial injection into the blastocoel and (2) seawater exposure to the marine bacterium Vibrio diazotrophicus to perturb immune state in the gut. Exposure at the epithelium induces a strong response in which pigment cells (one type of immune cell) migrate from the ectoderm to interact with the gut epithelium. Bacteria that accumulate in the gut later invade the blastocoel, where they are cleared by phagocytic and granular immune cells. The complexity of this coordinated, dynamic inflammatory program within the simple larval morphology provides a system in which to characterize processes that direct both aspects of the echinoderm-specific immune response as well as those that are shared with other deuterostomes, including vertebrates.
Views: 112 ScienceVio
Sea Urchins Pull Themselves Inside Out to be Reborn | Deep Look
 
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Conceived in the open sea, tiny spaceship-shaped sea urchin larvae search the vast ocean to find a home. After this incredible odyssey, they undergo one of the most remarkable transformations in nature. SUBSCRIBE to Deep Look! http://goo.gl/8NwXqt DEEP LOOK is a ultra-HD (4K) short video series created by KQED San Francisco and presented by PBS Digital Studios. See the unseen at the very edge of our visible world. Get a new perspective on our place in the universe. Explore big scientific mysteries by going incredibly small. * NEW VIDEOS EVERY OTHER TUESDAY! * Every summer, millions of people head to the coast to soak up the sun and play in the waves. But they aren’t alone. Just beyond the crashing surf, hundreds of millions of tiny sea urchin larvae are also floating around, preparing for one of the most dramatic transformations in the animal kingdom. Scientists along the Pacific coast are investigating how these microscopic ocean drifters, which look like tiny spaceships, find their way back home to the shoreline, where they attach themselves, grow into spiny creatures and live out a slow-moving life that often exceeds 100 years.“These sorts of studies are absolutely crucial if we want to not only maintain healthy fisheries but indeed a healthy ocean,” says Jason Hodin, a research scientist at the University of Washington’s Friday Harbor Laboratories. http://staff.washington.edu/hodin/ http://depts.washington.edu/fhl/ Sea urchins reproduce by sending clouds of eggs and sperm into the water. Millions of larvae are formed, but only a handful make it back to the shoreline to grow into adults. --- What are sea urchins? Sea urchins are spiny invertebrate animals. Adult sea urchins are globe-shaped and show five-point radial symmetry. They move using a system of tube feet. Sea urchins belong to the phylum Echinodermata along with their relatives the sea stars (starfish), sand dollars and sea slugs. --- What do sea urchins eat? Sea urchins eat algae and can reduce kelp forests to barrens if their numbers grow too high. A sea urchin’s mouth, referred to as Aristotle’s lantern, is on the underside and has five sharp teeth. The urchin uses the tube feet to move the food to its mouth. --- How do sea urchins reproduce? Male sea urchins release clouds of sperm and females release huge numbers of eggs directly into the ocean water. The gametes meet and the sperm fertilize the eggs. The fertilized eggs grow into free-swimming embryos which themselves develop into larvae called plutei. The plutei swim through the ocean as plankton until they drop to the seafloor and metamorphosize into the globe-shaped adult urchins. ---+ Read the entire article on KQED Science: https://ww2.kqed.org/science/2016/08/23/sea-urchins-pull-themselves-inside-out-to-be-reborn/ ---+ For more information: Marine Larvae Video Resource http://marinedevelopmentresource.stanford.edu/ ---+ More Great Deep Look episodes: From Drifter to Dynamo: The Story of Plankton | Deep Look https://www.youtube.com/watch?v=jUvJ5ANH86I Pygmy Seahorses: Masters of Camouflage | Deep Look https://www.youtube.com/watch?v=Q3CtGoqz3ww The Fantastic Fur of Sea Otters | Deep Look https://www.youtube.com/watch?v=Zxqg_um1TXI ---+ See some great videos and documentaries from PBS Digital Studios! It's Okay To Be Smart: Can Coral Reefs Survive Climate Change? https://www.youtube.com/watch?v=P7ydNafXxJI Gross Science: White Sand Beaches Are Made of Fish Poop https://www.youtube.com/watch?v=1SfxgY1dIM4 ---+ Follow KQED Science: KQED Science: http://www.kqed.org/science Tumblr: http://kqedscience.tumblr.com Twitter: https://www.twitter.com/kqedscience ---+ About KQED KQED, an NPR and PBS affiliate in San Francisco, CA, serves Northern California and beyond with a public-supported alternative to commercial TV, Radio and web media. Funding for Deep Look is provided in part by PBS Digital Studios and the John S. and James L. Knight Foundation. Deep Look is a project of KQED Science, which is also supported by HopeLab, the S. D. Bechtel, Jr. Foundation, the Dirk and Charlene Kabcenell Foundation, the Vadasz Family Foundation, the Gordon and Betty Moore Foundation, the Smart Family Foundation and the members of KQED. #deeplook #seaurchin #urchins
Views: 2981962 Deep Look
BU CGS NS 201 Sea Urchin Mitosis
 
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Video taken from NS 201 (Biology 1 - Human Genetics) at Boston University in the Fall of 2013
Views: 195 Andy Andres
sea urchin embryo fertilization and development
 
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Embryos of the purple sea urchin, Strongylocentrotus purpuratus, are shown in an accelerated time-lapse of fertilization and the first 15 hours of development. The stationary cells are eggs that did not fertilize.
Views: 85 Lauren Shipp
Fertilization in Sea Urchin | Chemotaxis Signalling
 
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In this video we have discussed about the fertilization in Sea Urchin. The Fertilization in Sea Urchin is driven by some chemical factors known as SAPs ( śpérm Activating Polypeptides ). The SAPs function is to guide the śperm towards the egg so that it can fertilize it. The SAPs bind to the cell membrane receptors of śperm cell and mediates the signalling pathway which ultimately leads to the motility of the flagella as described in the video. The fertilisation process is divided into 5 different steps : 1.Sperm Attraction : which involves Chemotaxis 2.Acrosomal Reaction : which involves interaction of sperm and Egg Jelly 3.Fusion of Egg and Sperm cell membrane . 4.Blocks to Polyspermy , where multiple sperms are blocked entry into the egg 5.Activation of egg metabolism. Here we have discussed the Chemotaxis only.
Views: 233 Hussain Biology
How I became part sea urchin | Catherine Mohr
 
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As a young scientist, Catherine Mohr was on her dream scuba trip -- when she put her hand right down on a spiny sea urchin. While a school of sharks circled above. What happened next? More than you can possibly imagine. Settle in for this fabulous story with a dash of science. Check out more TED Talks: http://www.ted.com The TED Talks channel features the best talks and performances from the TED Conference, where the world's leading thinkers and doers give the talk of their lives in 18 minutes (or less). Look for talks on Technology, Entertainment and Design -- plus science, business, global issues, the arts and more. Follow TED on Twitter: http://www.twitter.com/TEDTalks Like TED on Facebook: https://www.facebook.com/TED Subscribe to our channel: https://www.youtube.com/TED
Views: 71653 TED
Fertilization in sea urchin | Developmental biology lecture
 
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Fertilization in sea urchin- This developmental biology lecture explains about the fertilization process in sea urchin. It also explains the polyspermy prevention in sea urchin development. For more information, log on to- http://www.shomusbiology.com/ Get Shomu's Biology DVD set here- http://www.shomusbiology.com/dvd-store/ Download the study materials here- http://shomusbiology.com/bio-materials.html Remember Shomu’s Biology is created to spread the knowledge of life science and biology by sharing all this free biology lectures video and animation presented by Suman Bhattacharjee in YouTube. All these tutorials are brought to you for free. Please subscribe to our channel so that we can grow together. You can check for any of the following services from Shomu’s Biology- Buy Shomu’s Biology lecture DVD set- www.shomusbiology.com/dvd-store Shomu’s Biology assignment services – www.shomusbiology.com/assignment -help Join Online coaching for CSIR NET exam – www.shomusbiology.com/net-coaching We are social. Find us on different sites here- Our Website – www.shomusbiology.com Facebook page- https://www.facebook.com/ShomusBiology/ Twitter - https://twitter.com/shomusbiology SlideShare- www.slideshare.net/shomusbiology Google plus- https://plus.google.com/113648584982732129198 LinkedIn - https://www.linkedin.com/in/suman-bhattacharjee-2a051661 Youtube- https://www.youtube.com/user/TheFunsuman Thank you for watching
Views: 17199 Shomu's Biology
Sea Urchin Fertilization
 
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Sea Urchin Fertilization
Views: 393 GoAstros5
PREVENTION OF POLYSPERMY IN SEA URCHINS |FAST AND SLOW BLOCK |CSIR NET|DEVELOPMENTAL BIOLOGY
 
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WELCOME TO TEACHING PATHSHALA!! TOPIC-PREVENTION OF POLYSPERMY IN SEA URCHINS |FAST AND SLOW BLOCK OF POLYSPERMY |CSIR NET|DEVELOPMENTAL BIOLOGY Fast block to polyspermy –The fast block to polyspermy is achieved by changing the electric potential of the egg plasma membrane. Egg cell membrane initially have negative charge. This Negative charge will attract the positively charged sperm. During the entry of a sperm, the influx of Na+ ion in egg from sea environment will take place by the opening of Na+ ion channel The slow block to polyspermy-The eggs of sea urchins (and many other animals) have a second mechanism to ensure that multiple sperm do not enter the egg cytoplasm, which is also called cortical granule reaction. The fertilization envelope starts to form at the site of sperm entry and continues its expansion around the egg. As it forms, bound sperm are released from the envelope. This process starts about 20 seconds after sperm attachment and is complete by the end of the first minute of fertilization. The fast block to polyspermy is transient, since the membrane potential of the sea urchin egg remains positive for only about a minute. This brief potential shift is not sufficient to prevent polyspermy, which can still occur if the sperm bound to the vitelline envelope are not somehow removed ABOUT THIS CHANNEL ---This channel will have the syllabus wise lectures Video for CSIR-NET-Lifescience/GATE-Lifescience/BARC/ICMR-JRF/ICAR. ****** VIDEOS FROM DEVELOPMENTAL BIOLOGY UNIT-CSIR NET FERTILIZATION IN SEA URCHIN-CSIR NET | DEV BIO https://youtu.be/kAzL7VGpKRY C. elegans vulva formation (part-1) https://youtu.be/ati-iJ9zWKM C. elegan vulva development (part-2) https://youtu.be/el2SUaJhS4o CONCEPT OF INDUCTION AND COMPETENCE-CSIR NET https://youtu.be/ya_tj5W9FQ4 MORPHOGEN AND MORPHOGENIC GRADIENT-CSIR NET https://youtu.be/YQx1BJ_haS8 EYE LENS INDUCTION-CSIR NET https://youtu.be/FgyTxSejfaQ **************************************** AGROBACTERIUM MEDIATED GENE TRANSFER-CSIR NET https://youtu.be/9pj_SRs2z58 CSIR NET QUESTION ON AGROBACTERIUM MEDIATED GENE TRANSFER-- https://youtu.be/Zhnpao--wvs LIKE SHARE SUBSCRIBE FOR MORE SUCH VIDEOS THANK YOU !!
Views: 7682 TEACHING PATHSHALA
Sea Urchin Embryo Cilia
 
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Each peripheral cell of a sea urchin embryo (blastula stage) possesses on cilium. At high magnification (100X objective), cilia are observed individually while beating by DIC microscopy with stroboscopic illumination. The last part of the clip shows the ciliary anchoring structure present in each cell.
Views: 116 jacosson
Sea Urchin Development.wmv
 
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Highlight: Blastula, Early-Mid Gastrula
Views: 580 MsDCaba
Green Sea Urchin Blastula
 
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Green Sea Urchin Blastula under the microscope
Views: 836 mrandmrsslice
FERTILIZATION IN SEA URCHINS | CSIR NET LIFESCIENCE | DEVELOPMENTAL BIOLOGY
 
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WELCOME TO TEACHING PATHSHALA!!! TOPIC-FERTILIZATION IN SEA URCHINS |CSIR NET LIFESCIENCE | DEVELOPMENTAL BIOLOGY Chemo attraction of sperm towards the egg due to the secretion of soluble chemoattractant molecules by egg.Exocytosis of sperm acrosomal vesicles to release its enzyme and dissolve egg jelly.Binding of sperm to extracellular matrix/vitelline membrane. Species-specific recognition will be there. The acrosomal protein mediating this recognition is called bindin.(Interaction of EBR1 and bindin will take place).Passage of sperm through this extracellular matrix.Fusion of egg and sperm cell membrane. ABOUT THIS CHANNEL ---This channel will have the syllabus wise lectures Video for CSIR-NET-Lifescience/GATE-Lifescience/BARC/ICMR-JRF/ICAR. ****** VIDEOS FROM DEVELOPMENTAL BIOLOGY UNIT-CSIR NET C. elegans vulva formation (part-1) https://youtu.be/ati-iJ9zWKM C. elegan vulva development (part-2) https://youtu.be/el2SUaJhS4o CONCEPT OF INDUCTION AND COMPETENCE-CSIR NET https://youtu.be/ya_tj5W9FQ4 MORPHOGEN AND MORPHOGENIC GRADIENT-CSIR NET https://youtu.be/YQx1BJ_haS8 EYE LENS INDUCTION-CSIR NET https://youtu.be/FgyTxSejfaQ **************************************** AGROBACTERIUM MEDIATED GENE TRANSFER-CSIR NET https://youtu.be/9pj_SRs2z58 CSIR NET QUESTION ON AGROBACTERIUM MEDIATED GENE TRANSFER-- https://youtu.be/Zhnpao--wvs LIKE SHARE SUBSCRIBE FOR MORE SUCH VIDEOS THANK YOU !!
Views: 8138 TEACHING PATHSHALA
Tim Hunt recounts his discovery about cell division - Beautiful Minds - Ep3 Preview - BBC Four
 
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SUBSCRIBE to the OFFICIAL BBC YouTube channel: https://bit.ly/2IXqEIn LAUNCH BBC iPlayer to access Live TV and Box Sets: https://bbc.in/2J18jYJ http://www.bbc.co.uk/bbcfour More about this episode: http://www.bbc.co.uk/programmes/b00s2xv4 The final part of this series looking at three brilliant contemporary scientists features Sir Tim Hunt, awarded the Nobel Prize for his discovery of the mechanism of how cells divide - a discovery fundamental to the life and growth of every single creature on the planet, as well as a vital clue into the mystery of cancer. Hunt recalls moments in his life that provided inspiration for his career as a scientist, from his father's intent scholarship which shaped his early methods to his mother's battle with cancer and the influence of this on his current position at Cancer Research UK. In his own words, Hunt recounts the events that informed his discovery, from chance encounters to life-changing conversations and reveals his own opinions on the thought processes, both logical and emotional, that led to his extraordinary discovery. #bbc
Views: 9815 BBC
Homing in on Sea Urchin Eggs
 
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Homing in on Sea Urchin Eggs Video: Resetting of Ca2+ signals in single moving sperm. A sperm cell is loaded with the Ca2+ indicator Fluo-4 AM and caged cGMP. The cell is repeatedly stimulated by releasing cGMP from its caged derivative with six consecutive UV flashes. After each flash, the [Ca2+]i rapidly decreases and rises anew. The recording was performed using an epifluorescent microscope (IX71). Frames were acquired at 30 frames/s using a back-illuminated EM CCD camera (DU-897D). Photolysis of caged compounds was achieved using a mercury lamp (U-RFL-T). The irradiation time was controlled by a mechanical shutter (VS25). Laser stroboscopic illumination (488-nm wavelength and 2-ms pulse) was achieved using an acousto-optical tunable filter (AA Opto-Electronic Company). The fluorescence was filtered by a 500-nm long pass filter (500 ALP; Omega Optical, Inc.). Superposition of the scale bar and flash number to the original video was performed using MATLAB, and editing was finalized using VideoStudio Pro X4 (Corel Corporation). - Homing in on Sea Urchin Eggs http://news.sciencemag.org/sciencenow/2012/09/scienceshot-homing-in-on-sea-urc.html?ref=hp Reference Temporal sampling, resetting, and adaptation orchestrate gradient sensing in sperm Kashikar et al. 198 (6): 1075, September 17, 2012 JCB vol. 198 no. 6 1075-1091, doi: 10.1083/jcb.201204024 http://jcb.rupress.org/content/198/6/1075.abstract Abstract Sperm, navigating in a chemical gradient, are exposed to a periodic stream of chemoattractant molecules. The periodic stimulation entrains Ca2+ oscillations that control looping steering responses. It is not known how sperm sample chemoattractant molecules during periodic stimulation and adjust their sensitivity. We report that sea urchin sperm sampled molecules for 0.2--0.6 s before a Ca2+ response was produced. Additional molecules delivered during a Ca2+ response reset the cell by causing a pronounced Ca2+ drop that terminated the response; this reset was followed by a new Ca2+ rise. After stimulation, sperm adapted their sensitivity following the Weber--Fechner law. Taking into account the single-molecule sensitivity, we estimate that sperm can register a minimal gradient of 0.8 fM/µm and be attracted from as far away as 4.7 mm. Many microorganisms sense stimulus gradients along periodic paths to translate a spatial distribution of the stimulus into a temporal pattern of the cell response. Orchestration of temporal sampling, resetting, and adaptation might control gradient sensing in such organisms as well.
Views: 204 Stefano Di Criscio