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Cell Size: The quantity of volume or surface area of Cells.

Cell Size

JoVE 10688

The size of cells varies widely among and within organisms. For instance, the smallest bacteria are 0.1 micrometers (μm) in diameter—about a thousand times smaller than many eukaryotic cells. Most other bacteria are larger than these tiny ones—between 1-10 μm—but they still tend to be smaller than most eukaryotic cells, which typically range from 10-100 μm.

Larger is not necessarily better when it comes to cells. For instance, cells need to take in nutrients and water through diffusion. The plasma membrane surrounding cells limits the rate at which these materials are exchanged. Smaller cells tend to have a higher surface area to volume ratio than larger cells. That is because changes in volume are not linear to changes in surface area. When a sphere increases in size, the volume grows proportional to the cube of its radius (r3), while its surface area grows proportional to only the square of its radius (r2). Therefore, smaller cells have relatively more surface area compared to their volume than larger cells of the same shape. A larger surface area means more area of the plasma membrane where materials can pass into and out of the cell. Substances also need to travel within cells. Hence the rate of diffusion may limit processes in large cells. Prokaryotes are often small and divide before they face limitat

 Core: Cell Structure and Function

Diffusion and Osmosis- Concept

JoVE 10622

Cell Membranes and Diffusion

In order to function, cells are required to move materials in and out of their cytoplasm via their cell membranes. These membranes are semipermeable, meaning that certain molecules are allowed to pass through, but not others. This movement of molecules is mediated by the phospholipid bilayer and its embedded proteins, some of which act as transport channels…

 Lab Bio

Negative Regulator Molecules

JoVE 10764

Positive regulators allow a cell to advance through cell cycle checkpoints. Negative regulators have an equally important role as they terminate a cell’s progression through the cell cycle—or pause it—until the cell meets specific criteria.

Three of the best-understood negative regulators are p53, p21, and retinoblastoma protein (Rb). The regulatory roles of each of these proteins were discovered after faulty copies were found in cells with uncontrolled replication (i.e., cancer). These proteins exert most of their regulatory effects at the G1 checkpoint early in the cell cycle. P53 strongly influences a cell’s commitment to divide. It responds to DNA damage by discontinuing the cell cycle and summoning enzymes to repair the damage. If the DNA damage is irreparable, p53 can prevent the cell from proceeding through the cell cycle by inducing apoptosis, or cell death. An increase in p53 triggers the production of p21. P21 prevents the cell from transitioning from the G1 to the S phase of the cell cycle by binding to CDK/cyclin complexes, inhibiting their positive regulatory actions. Rb negatively regulates the cell cycle by acting on different positive regulators, mainly in response to cell size. Active (dephosphorylated) Rb binds to transcription factors, preventing them from initiating gene tran

 Core: Cell Cycle and Division

Diffusion and Osmosis - Student Protocol

JoVE 10564

Diffusion in Agar
NOTE: In this exercise, you will be given agar containing an indicator chemical called phenolphthalein. When phenolphthalein is exposed to the normal alkaline conditions in the agar, it will look pink. But when it is exposed to neutral or acidic conditions, it changes from pink to clear. You will make different size and shaped agar…

 Lab Bio

An Introduction to Endocytosis and Exocytosis

JoVE 5646

Cells can take in substances from the extracellular environment by endocytosis and actively release molecules into it by exocytosis. Such processes involve lipid membrane-bound sacs called vesicles. Knowledge of the molecular architecture and mechanisms of both is key to understanding normal cell physiology, as well as the disease states that arise when they become…

 Cell Biology

Diffusion and Osmosis - Prep Student

JoVE 10563

Preparation of Solutions for the Agar Cube Experiment
IMPORTANT: Wear gloves, goggles, and appropriate personal protective equipment – chemicals can be hazardous at high concentrations.
For the diffusion indicator solution, weigh out 1 g of phenolphthalein and add it to a beaker containing 100 mL of 95% ethanol.
To make the basic…

 Lab Bio

FM Dyes in Vesicle Recycling

JoVE 5648

FM dyes are a class of fluorescent molecules that has found important use in studying the vesicle recycling process. By virtue of a chemical structure, these molecules can insert themselves into the outer leaflet of phospholipid bilayer membranes. After membrane insertion, they are internalized into the cell via endocytosed vesicles, and released when these vesicles…

 Cell Biology

Automated Quantification of Hematopoietic Cell – Stromal Cell Interactions in Histological Images of Undecalcified Bone

1Immunodynamics, German Rheumatism Research Center, a Leibniz Institute, 2Biophysical Analytics, German Rheumatism Research Center, a Leibniz Institute, 3Max-Delbrück Center for Molecular Medicine, 4Wimasis GmbH, 5Immunodynamics and Intravital Imaging, Charité - University of Medicine

JoVE 52544

 Developmental Biology

Identification of Intracellular Signaling Events Induced in Viable Cells by Interaction with Neighboring Cells Undergoing Apoptotic Cell Death

1Section of Nephrology, Department of Medicine, University of Illinois at Chicago, 2Section of Nephrology, Department of Medicine, Jesse Brown Veterans Affairs Medical Center, 3Department of Biology, Kutztown University of Pennsylvania, 4Division of Rheumatology, Department of Medicine, Research Institute of the McGill University Health Centre, 5Department of Microbiology & Immunology, University of Illinois at Chicago

JoVE 54980

 Biology

A Cell-based Assay to Investigate Non-muscle Myosin II Contractility via the Folded-gastrulation Signaling Pathway in Drosophila S2R+ Cells

1Department of Biology, The University of North Carolina at Chapel Hill, 2Department of Biology, Reed College, 3Carolina Center for Genome Sciences, The University of North Carolina at Chapel Hill, 4Lineberger Comprehensive Cancer Center, The University of North Carolina at Chapel Hill

JoVE 58325

 Developmental Biology

Real-time Live-cell Flow Cytometry to Investigate Calcium Influx, Pore Formation, and Phagocytosis by P2X7 Receptors in Adult Neural Progenitor Cells

1Griffith Institute for Drug Discovery, Griffith University, 2Australian Institute for Bioengineering and Nanotechnology, University of Queensland, 3Discipline of Anatomy and Histology, School of Medical Science, University of Sydney, 4Bosch Institute, University of Sydney, 5Applied Neurosciences Program, Peter Duncan Neurosciences Research Unit, St. Vincent's Centre for Applied Medical Research, 6School of Medical Sciences, The University of New South Wales (UNSW) Medicine, Sydney, New South Wales, 7School of Environment and Science, Griffith University, Brisbane, Queensland, 8Florey Institute of Neuroscience and Mental Health, University of Melbourne

JoVE 59313

 Developmental Biology

Imaging Cell Interaction in Tracheal Mucosa During Influenza Virus Infection Using Two-photon Intravital Microscopy

1Faculty of Biomedical Sciences, Institute for Research in Biomedicine, Università della Svizzera italiana (USI), 2Graduate School of Cellular and Molecular Sciences, Faculty of Medicine, University of Bern, 3Institute of Computational Science, Università della Svizzera italiana (USI)

JoVE 58355

 Immunology and Infection

Isolation of Retinal Arterioles for Ex Vivo Cell Physiology Studies

1Centre for Experimental Medicine, Queen's University of Belfast, 2Centre for Biomedical Sciences (Education), Queen's University of Belfast, 3Department of Pharmaceutical Chemistry and Pharmacognosy, Naresuan University, 4School of Medicine, Dentistry and Biomedical Sciences, Queen's University of Belfast

JoVE 57944

 Biology

In Situ Detection and Single Cell Quantification of Metal Oxide Nanoparticles Using Nuclear Microprobe Analysis

1Centre d'Etudes Nucléaires Bordeaux Gradignan (CENBG), Université de Bordeaux, 2Centre d'Etudes Nucléaires Bordeaux Gradignan (CENBG), CNRS, 3Institut de Chimie de la Matière Condens é e de Bordeaux (ICMCB), CNRS, 4Institut de Chimie de la Matière Condens é e de Bordeaux (ICMCB), Université de Bordeaux

JoVE 55041

 Chemistry

Measuring Intracellular Ca2+ Changes in Human Sperm using Four Techniques: Conventional Fluorometry, Stopped Flow Fluorometry, Flow Cytometry and Single Cell Imaging

1Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología-Universidad Nacional Autónoma de México, 2Math and Sciences Department, Edison State College

JoVE 50344

 Biology

Isolation of Single Intracellular Bacterial Communities Generated from a Murine Model of Urinary Tract Infection for Downstream Single-cell Analysis

1Infectious Diseases Group, Genome Institute of Singapore, 2Department of Chemical and Biomolecular Engineering, National University of Singapore, 3Division of Infectious Diseases, Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore

JoVE 58829

 Immunology and Infection

Tumorsphere Derivation and Treatment from Primary Tumor Cells Isolated from Mouse Rhabdomyosarcomas

1Graduate School of Biomedical Sciences, Sanford Burnham Prebys Medical Discovery Institute, 2Development, Aging and Regeneration Program, Sanford Burnham Prebys Medical Discovery Institute, 3Department of Obstetrics, Gynecology, and Reproductive Sciences, Division of Female Pelvic Medicine and Reconstructive Surgery, University California San Diego

JoVE 59897

 Genetics

Isolation of Primary Murine Retinal Ganglion Cells (RGCs) by Flow Cytometry

1Department of Ophthalmology, Hamilton Eye Institute, University of Tennessee Health Science Center, 2Department of Microbiology, Immunology and Biochemistry, University of Tennessee Health Science Center, 3Department of Anatomy and Neurobiology, University of Tennessee Health Science Center, 4Department of Pharmaceutical Sciences, University of Tennessee Health Science Center

JoVE 55785

 Bioengineering

Multiplexed Immunofluorescence Analysis and Quantification of Intratumoral PD-1+ Tim-3+ CD8+ T Cells

1PARCC-INSERM U970, Université Paris Descartes, 2INSERM U970, Université Paris Descartes, 3Equipe Labellisée Ligue Contre le Cancer, 4Department of Immunology, Hopital Européen Georges Pompidou, 5Department of Medical Urology, Hopital Européen Georges Pompidou, 6Department of Pathology, Hopital Européen Georges Pompidou, 7Université Paris Diderot Paris 7, 8Department of medical oncology, Hopital Européen Georges Pompidou

JoVE 56606

 Cancer Research

A Stainless Protocol for High Quality RNA Isolation from Laser Capture Microdissected Purkinje Cells in the Human Post-Mortem Cerebellum

1Department of Pathology and Cell Biology, Columbia University, 2Division of Movement Disorders, Department of Neurology, Yale University, 3Department of Chronic Disease Epidemiology, Yale School of Public Health, Yale University, 4Center for Neuroepidemiology and Clinical Neurological Research, Yale School of Medicine, Yale University

JoVE 58953

 Neuroscience
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