Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Synthesis and Functions of Calcitonin00:51

Synthesis and Functions of Calcitonin

Calcitonin, a vital polypeptide hormone, regulates calcium levels within body fluids. It is released by the parafollicular cells, also known as C cells, situated in the follicular epithelium of the thyroid gland. Calcitonin responds to fluctuations in blood calcium levels and the influence of gastrointestinal hormones like gastrin and cholecystokinin.
The exact mechanisms by which calcitonin operates in calcium homeostasis remain elusive, but its significance is evident in several vital...
Archaeal Cell Wall01:29

Archaeal Cell Wall

Archaeal cell walls are structurally and compositionally distinct from their bacterial counterparts, lacking the characteristic peptidoglycan layer found in most bacteria. Instead, archaeal cell walls exhibit remarkable diversity, utilizing materials such as pseudomurein, polysaccharides, and proteins to construct their protective outer layers. This structural flexibility is closely tied to archaea's ecological adaptability.S-Layers: The Common Archaeal Cell WallThe S-layer is the most...
Ionic Crystal Structures02:42

Ionic Crystal Structures

Ionic crystals consist of two or more different kinds of ions that usually have different sizes. The packing of these ions into a crystal structure is more complex than the packing of metal atoms that are the same size.
Most monatomic ions behave as charged spheres, and their attraction for ions of opposite charge is the same in every direction. Consequently, stable structures for ionic compounds result (1) when ions of one charge are surrounded by as many ions as possible of the opposite...
The Bone Matrix01:18

The Bone Matrix

Bone contains a relatively small number of cells entrenched in a matrix of collagen fibers that provide an adherent surface for inorganic salt crystals. Both components of the matrix, organic and inorganic, contribute to the unusual properties of bone. Without collagen, bones would be brittle and shatter easily. Without mineral crystals, bones would flex and provide little support. This can be observed by an experiment: when the minerals of a bone are dissolved by soaking the bone in acid or...
Hydration of Cement01:24

Hydration of Cement

Hydration of cement is a chemical reaction between cement particles and water. This process occurs primarily through two mechanisms: through-solution and topochemical. In the through-solution process, anhydrous compounds dissolve into their constituents, hydrates form in the solution, and then precipitate from the supersaturated solution. The topochemical process involves solid-state reactions at the cement particle surface. The through-solution process dominates the topochemical process at the...
Diversity of Protists III01:27

Diversity of Protists III

Rhizaria are a diverse group of unicellular protists characterized by their threadlike cytoplasmic extensions known as pseudopodia. These structures aid in both locomotion and feeding, giving Rhizaria an amoeboid appearance. Their amoeboid morphology once led to taxonomic confusion, but molecular phylogenetics has clarified their evolutionary placement and emphasized their shared use of pseudopodia despite divergent lineages.This clade comprises diverse lineages such as Chlorarachniophyta,...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Comparison of rhapidosomes and asbestos microfibrils.

Science (New York, N.Y.)·1978
See all related articles

Related Experiment Video

Updated: Jul 12, 2026

Microbiologically Induced Calcite Precipitation Mediated by Sporosarcina pasteurii
09:04

Microbiologically Induced Calcite Precipitation Mediated by Sporosarcina pasteurii

Published on: April 16, 2016

Synthetic calcareous pseudomorphs formed from siliceous microstructures.

R I Harker

    Science (New York, N.Y.)
    |July 16, 1971
    PubMed
    Summary

    Diatoms were hydrothermally treated with lime and carbon dioxide, resulting in calcite pseudomorphs. The original silica structure was replaced, preserving intricate micro-details of the diatom fossils.

    Area of Science:

    • Biomineralization
    • Paleontology
    • Materials Science

    Background:

    • Diatoms possess intricate silica frustules.
    • Biomineralization processes offer insights into fossilization.
    • Hydrothermal treatments can alter mineral structures.

    Purpose of the Study:

    • To investigate the hydrothermal pseudomorphism of diatoms.
    • To explore the preservation of micro-architectural details during mineral replacement.
    • To synthesize calcite pseudomorphs from diatom templates.

    Main Methods:

    • Hydrothermal treatment of Coscinodiscus diatoms.
    • Use of lime (calcium hydroxide) and carbon dioxide.
    • Microscopic analysis (SEM, TEM) to observe structural preservation.

    More Related Videos

    Characterization of Calcification Events Using Live Optical and Electron Microscopy Techniques in a Marine Tubeworm
    15:39

    Characterization of Calcification Events Using Live Optical and Electron Microscopy Techniques in a Marine Tubeworm

    Published on: February 28, 2017

    Calcium Carbonate Formation in the Presence of Biopolymeric Additives
    09:31

    Calcium Carbonate Formation in the Presence of Biopolymeric Additives

    Published on: May 14, 2019

    Related Experiment Videos

    Last Updated: Jul 12, 2026

    Microbiologically Induced Calcite Precipitation Mediated by Sporosarcina pasteurii
    09:04

    Microbiologically Induced Calcite Precipitation Mediated by Sporosarcina pasteurii

    Published on: April 16, 2016

    Characterization of Calcification Events Using Live Optical and Electron Microscopy Techniques in a Marine Tubeworm
    15:39

    Characterization of Calcification Events Using Live Optical and Electron Microscopy Techniques in a Marine Tubeworm

    Published on: February 28, 2017

    Calcium Carbonate Formation in the Presence of Biopolymeric Additives
    09:31

    Calcium Carbonate Formation in the Presence of Biopolymeric Additives

    Published on: May 14, 2019

    Main Results:

    • Successful pseudomorphism of diatoms into calcite.
    • Complete replacement of diatom silica by calcite.
    • Preservation of intricate alveolar reticulations down to submicroscopic levels.

    Conclusions:

    • Hydrothermal carbonation is an effective method for diatom pseudomorphism.
    • This process preserves fine structural details, valuable for paleontology.
    • Calcite pseudomorphs serve as potential templates for novel materials.