About the Author. The first menarche indicates girls have begun to ovulate; i. The increased secretion of testosterone from the testes during puberty causes the male secondary sexual characteristics to be manifested.
On average, the testes will begin to enlarge at about 11 years of age, but this growth can occur anytime between 9 and 13 years.
Photo Credits. Hormones and Reproduction of Vertebrates, Volume 1. Some reptile species, including most turtles and all crocodilians, utilize temperature-dependent sex determination to control the sex ratios number of males to females of their offspring.
Estradiol and other hormones cause breasts to develop in females. Although at puberty he has signs of virilization, he has developed pronounced gynecomastia. Cengage Learning. Secondary sex characteristics are features that appear during puberty in humansand at sexual maturity in other animals.
Among females this consists mainly of the vagina, the uterus and the ovaries. This category only includes cookies that ensures basic functionalities and security features of the website. The Y chromosome from the father has a specialized gene responsible for the determination of testes during foetal development; otherwise, the gonads will develop into ovaries.
In the animal world, there are many examples to describe secondary sexual characteristics. Each individual response is reinforced, and is followed by another response till the complex behavior is accomplished. In this sense, the family operates as a factory that produces the necessary type of personality.
If you noticed, the incident is divided into fragments denoting individual responses. You also have the option to opt-out of these cookies.
These movement skills are divided into two types: gross motor skills and fine motor skills. Examples for male and female primary characteristics include penis, testicles, epididymis, prostate, scrotum, cervix, clitoris, fallopian tubes, uterus, vulva, vagina…etc.
Namespaces Article Talk. The increased secretion of testosterone from the testes during puberty causes the male secondary sexual characteristics to be manifested. Any anatomical part involved with the reproductive system of an organism is a sexual organ, aka primary sexual characteristic. From Wikipedia, the free encyclopedia.