Related Experiment Video

Updated: Sep 20, 2026

Anogenital Distance and Perineal Measurements of the Pelvic Organ Prolapse (POP) Quantification System
03:49

Anogenital Distance and Perineal Measurements of the Pelvic Organ Prolapse (POP) Quantification System

Published on: September 20, 2018

Environmental factors and the proportion of males at birth in Italy

Irene Figà-Talamanca1, Pietro Carbone, Laura Lauria

  • 1Department of Animal and Human Biology, University of Rome "La Sapienza", Rome, Italy. irene.figatalamanca@uniroma1.it

Archives of Environmental Health
|August 6, 2003
PubMed

More Related Videos

Mass Production of Genetically Modified Aedes aegypti for Field Releases in Brazil17:41

Mass Production of Genetically Modified Aedes aegypti for Field Releases in Brazil

Published on: January 4, 2014

Determining the Egg Fertilization Rate of Bemisia tabaci Using a Cytogenetic Technique05:24

Determining the Egg Fertilization Rate of Bemisia tabaci Using a Cytogenetic Technique

Published on: April 1, 2019

Related Concept Videos

Background and Environment Affect Phenotype02:27

Background and Environment Affect Phenotype

Although the genetic makeup of an organism plays a major role in determining the phenotype, there are also several environmental factors, such as temperature, oxygen availability, presence of mutagens, that can alter an organism’s phenotype.
An example of how genetic background affects phenotype can be seen in horses. The Extension gene in horses is responsible for their coat color. A wild-type gene (EE) produces black pigment in the coat, while a mutant gene (ee) produces red pigment. A...
Natural Selection and Mating Preferences01:06

Natural Selection and Mating Preferences

The principle of natural selection posits that organisms better adapted to their environment are more likely to survive and reproduce. This principle is closely intertwined with mating preferences, a key aspect of sexual selection, which evolutionary psychologists believe is driven by instincts to propagate one's genes. Such instincts significantly influence mating behaviors and preferences between genders.
Females, due to their biological roles in conception, pregnancy, and nursing, inherently...
Infertility in Males01:23

Infertility in Males

Male infertility affects millions of couples worldwide, arising from various factors that impact different stages of the reproductive process. An endocrine imbalance resulting from conditions like hypogonadism, Klinefelter syndrome, or pituitary disorders can disrupt hormone levels and reduce sperm production. Testicular defects, such as tumors, cryptorchidism, atrophic testes, abnormal sperm morphology, and low sperm count or motility, may arise due to genetic factors, structural...
The Ratio of X Chromosome to Autosomes02:45

The Ratio of X Chromosome to Autosomes

In most organisms, sex is determined by the ratio of X and Y chromosomes. However, in some organisms, such as Drosophila and C.elegans, sex is determined by the ratio of the number of X chromosomes to the number of sets of autosomes. The Y chromosome in Drosophila is active but does not determine sex. It contains genes responsible for the production of sperms in adult flies.  
Normal male Drosophila has a ratio of one X chromosome to two sets of autosomes. In contrast, normal female Drosophila...
Socioemotional Experience and Gender Development01:30

Socioemotional Experience and Gender Development

Social-emotional experiences and cultural influences play significant roles in shaping gender development. During middle childhood, from ages 6 to 11, peer groups become dominant in reinforcing gender norms. Children in this age group often align with same-gender peer groups, which actively encourage behaviors that conform to traditional gender roles. For instance, boys may be discouraged from engaging in activities perceived as feminine, reinforcing culturally dictated norms about masculinity...
The Y Chromosome Determines Maleness02:19

The Y Chromosome Determines Maleness

The Y chromosome is a sex chromosome found in several vertebrates and mammals, including humans. In addition to 22 pairs of autosomes, the human males have one X chromosome and one Y chromosome. In these organisms, the presence or absence of the Y chromosome determines the development of male traits.
Evolution
Around 300 million years ago, the two sex chromosomes diverged from two identical autosomal chromosomes. Over time, the Y chromosome has lost most of its genes, shrinking in size. Today,...