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

Development of the Sexual Organs in the Embryo and Fetus01:15

Development of the Sexual Organs in the Embryo and Fetus

5.5K
Development of the reproductive organs in an embryo starts from a bipotential state. This means the early embryo can develop either male or female reproductive organs. The formation of these organs begins with the growth of gonadal ridges that arise from the intermediate mesoderm during the fifth week of development.
Near the gonadal ridges, two duct systems are present: the mesonephric ducts (Wolffian ducts) and paramesonephric ducts (Müllerian ducts). These ducts form the basis for the...
5.5K
Penis01:29

Penis

49.5K
The penis serves a dual role in sexual reproduction and urination. It consists of three main regions: the glans penis, the body, and the root, each with distinct functions and unique anatomical features.
Anatomy of the Penis
The glans penis, or the head, is the terminal part of the penis and houses the external urethral orifice, the exit point for urine and semen. Covered by the prepuce, or foreskin, the glans is noted for its sensitivity and plays a key role in sexual pleasure. The body of the...
49.5K
Development of Blood Vessels01:07

Development of Blood Vessels

2.0K
The development of the vascular system in a fetus is a complex and intricate process that begins as early as 15 to 16 days post-conception. This process starts outside the embryo, specifically in the mesoderm of the yolk sac, chorion, and connecting stalk. Approximately two days later, the formation of blood vessels occurs within the embryo itself.
The initial formation of this system is facilitated by the small amount of yolk present in the ovum and yolk sac. Blood vessels originate from...
2.0K
Spermatogenesis01:41

Spermatogenesis

90.6K
Spermatogenesis is the process by which haploid sperm cells are produced in the male testes. It starts with stem cells located close to the outer rim of seminiferous tubules. These spermatogonial stem cells divide asymmetrically to give rise to additional stem cells (meaning that these structures “self-renew”), as well as sperm progenitors, called spermatocytes. Importantly, this method of asymmetric mitotic division maintains a population of spermatogonial stem cells in the male...
90.6K
Accessory Ducts of the Male Reproductive System01:25

Accessory Ducts of the Male Reproductive System

4.6K
The male reproductive system is a complex network of organs and tissues that work together to produce and transport sperm. The epididymis, vasa deferens, ejaculatory ducts, and urethra are the accessory ducts involved in sperm maturation and transportation. These ducts play a critical role in the production and transportation of sperm from the testes to the urethra, where it is then released during ejaculation.
The epididymis is a small, comma-shaped organ located at the back of each testicle....
4.6K
Changes in the Appendicular Skeleton with Age01:09

Changes in the Appendicular Skeleton with Age

3.2K
The upper and lower limb initially develops as a small bulge called a limb bud, which appears on the lateral side of the early embryo. The upper limb bud appears near the end of the fourth week of development, with the lower limb bud appearing shortly after.
Initially, the limb buds consist of a core of mesenchyme covered by a layer of ectoderm. The ectoderm at the end of the limb bud thickens to form a narrow crest called the apical ectodermal ridge. This ridge stimulates the underlying...
3.2K

You might also read

Related Articles

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

Sort by
Same author

Disruption of carotenoid metabolism in cavefish via loss of beta-carotene oxygenase 2a.

Current biology : CB·2026
Same author

Adaptive Disruption of Carotenoid Metabolism in Cavefish via Loss of Beta-carotene oxygenase 2a (Bco2a).

bioRxiv : the preprint server for biology·2025
Same author

Endoderm differentiates into a transient epidermis in the mouse perineum.

Developmental dynamics : an official publication of the American Association of Anatomists·2025
Same author

Endoderm differentiates into a transient epidermis in the mouse perineum.

bioRxiv : the preprint server for biology·2025
Same author

COVID-19 and the Latinx Community: "Promotoras Represent a Community in Pain".

Journal of Latina/o psychology·2023
Same author

Examining Interpersonal Traumas Across Low Income Latinx Mother-Youth Dyads: Associations Between Maternal Child Abuse Exposure and Racial Discrimination with Mother and Youth Psychopathology.

Child psychiatry and human development·2022
Same journal

Differences in early development between parental species and asexual hybrids forms of European spined loaches (genus Cobitis).

Sexual development : genetics, molecular biology, evolution, endocrinology, embryology, and pathology of sex determination and differentiation·2026
Same journal

Cytogenomic Investigation of Individuals with Ovotesticular Difference of Sex Development.

Sexual development : genetics, molecular biology, evolution, endocrinology, embryology, and pathology of sex determination and differentiation·2026
Same journal

A Case of Disorder of Sex Development in Red Deer (<italic>Cervus elaphus</italic>).

Sexual development : genetics, molecular biology, evolution, endocrinology, embryology, and pathology of sex determination and differentiation·2026
Same journal

<italic>WT1</italic> Deletion in 46,XY DSD: The Importance of Copy Number Variant Analysis.

Sexual development : genetics, molecular biology, evolution, endocrinology, embryology, and pathology of sex determination and differentiation·2026
Same journal

XX/XY Chimerism in Tortoiseshell Tomcats: A New Case and Review of the Literature.

Sexual development : genetics, molecular biology, evolution, endocrinology, embryology, and pathology of sex determination and differentiation·2026
Same journal

Functional Validation of a Novel <italic>PBX1</italic> Missense Variant in a 46,XY Girl.

Sexual development : genetics, molecular biology, evolution, endocrinology, embryology, and pathology of sex determination and differentiation·2026
See all related articles

Related Experiment Video

Updated: Apr 27, 2026

Induction and Evaluation of Inbreeding Crosses Using the Ant, Vollenhovia Emeryi
06:44

Induction and Evaluation of Inbreeding Crosses Using the Ant, Vollenhovia Emeryi

Published on: October 5, 2018

7.1K

Development of hemipenes in the ball python snake Python regius.

Francisca Leal1, Martin J Cohn

  • 1Department of Biology, University of Florida, Gainesville, Fla., USA.

Sexual Development : Genetics, Molecular Biology, Evolution, Endocrinology, Embryology, and Pathology of Sex Determination and Differentiation
|June 28, 2014
PubMed
Summary
This summary is machine-generated.

Snake hemipenes develop differently from other amniote genitalia, lacking key embryonic tissues and signaling pathways. Despite distinct origins, some shared developmental genes suggest conserved mechanisms in external genital evolution.

More Related Videos

Formation of Human Prostate Epithelium Using Tissue Recombination of Rodent Urogenital Sinus Mesenchyme and Human Stem Cells
08:44

Formation of Human Prostate Epithelium Using Tissue Recombination of Rodent Urogenital Sinus Mesenchyme and Human Stem Cells

Published on: June 22, 2013

13.4K
Phosphopeptide Analysis of Rodent Epididymal Spermatozoa
09:30

Phosphopeptide Analysis of Rodent Epididymal Spermatozoa

Published on: December 30, 2014

16.6K

Related Experiment Videos

Last Updated: Apr 27, 2026

Induction and Evaluation of Inbreeding Crosses Using the Ant, Vollenhovia Emeryi
06:44

Induction and Evaluation of Inbreeding Crosses Using the Ant, Vollenhovia Emeryi

Published on: October 5, 2018

7.1K
Formation of Human Prostate Epithelium Using Tissue Recombination of Rodent Urogenital Sinus Mesenchyme and Human Stem Cells
08:44

Formation of Human Prostate Epithelium Using Tissue Recombination of Rodent Urogenital Sinus Mesenchyme and Human Stem Cells

Published on: June 22, 2013

13.4K
Phosphopeptide Analysis of Rodent Epididymal Spermatozoa
09:30

Phosphopeptide Analysis of Rodent Epididymal Spermatozoa

Published on: December 30, 2014

16.6K

Area of Science:

  • Developmental Biology
  • Evolutionary Biology
  • Comparative Anatomy

Background:

  • Amniotes exhibit diverse external copulatory organ morphologies.
  • Squamate hemipenes (lizards and snakes) represent an extreme example of this diversification.
  • Hemipenes are paired organs originating from the cloaca's lateral margins.

Purpose of the Study:

  • To describe the embryonic development of hemipenes in the ball python (Python regius).
  • To compare the developmental origins and patterning mechanisms of snake hemipenes with non-squamate amniote genitalia.
  • To investigate potential homologous developmental pathways in amniote external genital evolution.

Main Methods:

  • Embryonic description of hemipene development in Python regius.
  • Comparative analysis of developmental gene expression patterns.
  • Histological and molecular characterization of cloacal and genital tubercle development.

Main Results:

  • Snake hemipenes develop from paired lateral swellings of the cloaca.
  • Unlike non-squamate amniotes, hemipenes lack an endodermal contribution and Sonic hedgehog (Shh) expression in the sulcus.
  • Despite differences, some gene expression patterns in hemipene buds resemble those in non-squamate genital tubercles.

Conclusions:

  • Snake hemipenes possess unique embryonic origins and patterning mechanisms compared to non-squamate amniote genitalia.
  • Hemipenes may not be direct homologs of the unpaired amniote penis.
  • Conserved developmental gene expression suggests homologous mechanisms underlie aspects of external genital development across amniotes, despite independent origins.