Welcome to The Visible Embryo

Home- - -History-- -Bibliography- -Pregnancy Timeline- --Prescription Drugs in Pregnancy- -- Pregnancy Calculator- --Female Reproductive System- News Alerts -Contact

Welcome to The Visible Embryo, a comprehensive educational resource on human development from conception to birth.

The Visible Embryo provides visual references for changes in fetal development throughout pregnancy and can be navigated via fetal development or maternal changes.

The National Institutes of Child Health and Human Development awarded Phase I and Phase II Small Business Innovative Research Grants to develop The Visible Embryo. Initally designed to evaluate the internet as a teaching tool for first year medical students, The Visible Embryo is linked to over 600 educational institutions and is viewed by more than ' million visitors each month.


WHO International Clinical Trials Registry Platform
The World Health Organization (WHO) has created a new Web site to help researchers, doctors and patients obtain reliable information on high-quality clinical trials. Now you can go to one website and search all registers to identify clinical trial research underway around the world!



Home

History

Bibliography

Pregnancy Timeline

Prescription Drug Effects on Pregnancy

Pregnancy Calculator

Female Reproductive System

Contact The Visible Embryo

News Alerts Archive

Disclaimer: The Visible Embryo web site is provided for your general information only. The information contained on this site should not be treated as a substitute for medical, legal or other professional advice. Neither is The Visible Embryo responsible or liable for the contents of any websites of third parties which are listed on this site.
Content protected under a Creative Commons License.

No dirivative works may be made or used for commercial purposes.

Return To Top Of Page
Pregnancy Timeline by SemestersFetal liver is producing blood cellsHead may position into pelvisBrain convolutions beginFull TermWhite fat begins to be madeWhite fat begins to be madeHead may position into pelvisImmune system beginningImmune system beginningPeriod of rapid brain growthBrain convolutions beginLungs begin to produce surfactantSensory brain waves begin to activateSensory brain waves begin to activateInner Ear Bones HardenBone marrow starts making blood cellsBone marrow starts making blood cellsBrown fat surrounds lymphatic systemFetal sexual organs visibleFinger and toe prints appearFinger and toe prints appearHeartbeat can be detectedHeartbeat can be detectedBasic Brain Structure in PlaceThe Appearance of SomitesFirst Detectable Brain WavesA Four Chambered HeartBeginning Cerebral HemispheresFemale Reproductive SystemEnd of Embryonic PeriodEnd of Embryonic PeriodFirst Thin Layer of Skin AppearsThird TrimesterSecond TrimesterFirst TrimesterFertilizationDevelopmental Timeline
Click weeks 0 - 40 and follow fetal growth
Google Search artcles published since 2007
 
September 30, 2011--------News Archive

Estrodial A Unisex Hormone Essential To Metabolism
Possible treatment options could result for diabetes, obesity and heart disease.

Remove Fibroids - Prevent Recurrent Miscarriages
Research has found the first, firm evidence that fibroids are associated with recurrent miscarriages.

Understanding How Brain White Matter Develops
Study findings indicate a key step in the generation of white matter and understanding developmental disabilities.

'Alarm Clock' Gene Wakes-Up Biological Clock
Finding promises insight into sleeplessness, aging and chronic illness, such as diabetes and cancer.

September 29, 2011--------News Archive

Control Gene for Developmental Timing Discovered
Research has identified a key regulator controlling the speed of development in fruit flies. Blocking this regulator sped up the animals' rate of maturity.

Low Zinc/Copper Might Cause Spontaneous Abortion
This hypothesis had never been proven before in humans, and now has been demonstrated by University of Granada research.

Scientists Identify New Brain Stem Cell Activity
Finding raises questions of how the human brain develops and evolves.

Millesecond Memory
'Teleportation' of rats sheds light on how the memory is organized.

September 28, 2011--------News Archive

What Do Infants Remember, What Do They Forget?
In fact, they understand that objects once seen, should not disappear.

Found: New Gene Region for Testicle Development
Research has found a new genetic region which may control testicle development in the foetus.

September 27, 2011--------News Archive

Severe/Moderate Preemie Lung Function Improves
The negative effects of premature birth, whether moderately premature or extremely so, may be reversed by their teenage years.

Mom's Exercise Protects Baby From Alzheimer's
New research suggests prenatal exercise improves brain plasticity, decreases toxic protein deposits, inflammation and oxidative stress, warding off Alzheimer's.

Predicting the Best Treatment for Breast Cancer
Researchers identify new genes that help determine breast cancer prognosis.

September 26, 2011--------News Archive

Key Step Reprograms Adult Cells to Mimic Stem Cells
UNC researchers identify an important difference in sperm cell reprogramming needed to initiate formation of the embryo.

First USA Embryonic Stem Cell Therapy for Paralysis
The trial is being run by Geron Corp. of Menlo Park, Calif., which developed and manufactures the cells being tested.

UK Begins Stem Cell Trial for Disorder of the Retina
Experimental new treatment could offer hope to young people suffering from a currently untreatable inherited eye condition.

Pregnancy Occupation Can Cause Asthma in Child
Mothers who are exposed to particular agents during pregnancy could give birth to children with a higher risk of asthma, according to new research.

WHO Child Growth Charts


Sperm and egg. Images: NIH


When sperm meets egg, the chemical instructions on sperm cells must be erased so that human life can start anew.

One way these instructions are erased is through demethylation, the removal of the chemical tags known as methyl groups that dot the underlying DNA of cells. Though scientists have known about this phenomenon for a decade, they have not understood how such “reprogramming” occurs.

Now, a study from the University of North Carolina at Chapel Hill, School of Medicine, has illuminated a key step of demethylation giving stem cell researchers critical information as they attempt to reprogram adult cells to become stem cells.

Previous research had identified how methyl tags on sperm DNA are converted to hydroxymethyl, before disappearing completely. The current research, published online in the Sept. 22, 2011, issue of Science (ScienceExpress), suggests that the disappearance of these chemical tags in not an active process catalyzed by an enzyme but is rather a passive process.

“The biological function of this molecular event is not known yet, we are still trying to figure it out,” said senior study author Yi Zhang, PhD, Kenan distinguished professor of biochemistry and biophysics at UNC and an investigator of the Howard Hughes Medical Institute.

“But we do believe it must be important for development, because it happens before the cells committed to any specific cell types.” Zhang is also a member of the UNC Lineberger Comprehensive Cancer Center.

Zhang’s postdoctoral fellow and co-author Azusa Inoue, PhD, developed a technique that enabled him to visualize chromosomes – the threadlike bodies that contain the cell’s DNA – at the earliest stage of life.

Through a high resolution staining technique, he was able to compare the levels of methyl tags and hydroxymethyl tags in sperm and egg chromosomes in the first developmental stages of life.

Their findings confirmed what they already knew – that sperm DNA goes through a chemical conversion from methyl to hydroxylmethyl while the egg DNA does not.

But it also found something new – that the hydroxymethyl tags disappeared over time, passively through dilution, as the DNA divided and the newly formed embryo doubled from first one-cell, then to two- and four-cells.

The clinical implications are still not clear, Zhang says, as researchers still don’t know why male DNA undergoes such a conversion when female DNA does not.

It may have something to do with difference between the chromatin protein structure that packages the DNA of the sperm and of the egg. Zhang and others in the field are actively pursuing this possibility.

The research was funded by the Howard Hughes Medical Institute and the National Institutes of Health.

Original article: http://news.unchealthcare.org/news/2011/september/unc-researchers-identify-important-step-in-sperm-reprogramming