An official website of the United States government
The .gov means it’s official. Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.
The site is secure. The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.
National Institute of Environmental Health Sciences
Use this QR code to view the newest version of this document
Central Nervous System: A guide to the development of the mouse central nervous system from embryonic days 7.5-18.5, including representative histology images. (Last reviewed February 2026)
Heart: A guide to the development of the mouse heart from embryonic days 11.5-18.5, including representative histology images. (Last reviewed February 2026)
Hepatobiliary System: A guide to the development of the mouse hepatobiliary system from embryonic days 9.5-18.5, including representative histology images. (Last reviewed February 2026)
Hepatobiliary Hemolymphatic Vascular System: A guide to the development of the mouse hepatobiliary hemolymphatic vascular system from embryonic days 11.5-18.5 and early postnatal timepoints, including representative histology images. (Last reviewed February 2026)
Placenta: A guide to the development of the mouse placenta from embryonic days 4.5–18.5, including representative histology and immunohistochemistry images. (Last Reviewed February 2026)
Respiratory System: A guide to the development of the mouse respiratory system from embryonic day 9.0 to postnatal day 30, including representative histology images. (Last Reviewed February 2026)
Urinary System: A guide to the development of the mouse urinary system from embryonic days 10.5-18.5, including representative histology images. (Last reviewed February 2026)