The main biological differences between males and females are the fertility and the reproductive organs. Males are continuously fertile from puberty due to the continuous production of sperms whereas females are fertile for 12 hours each month until menopause. Also, male reproductive organs include penis, scrotum, and testicles while female reproductive organs include vagina, uterus, and ovaries.
Males are obviously different from females in terms of their anatomy and physiology due to biological and genetic reasons. Most of these differences are due to the chemical reactions of hormones.
Key Areas Covered
1. What are Special Biological Characteristics of Males
– Reproductive System, Hormones, Fertility
2. What are Special Biological Characteristics of Females
– Reproductive System, Hormones, Fertility
3. What are the Biological Similarities Between Males and Females
– Outline of Common Features
4. What are the Biological Differences Between Males and Females
– Comparison of Common Features
Key Terms: Estrogen, Females, Fertility, Males, Progesterone, Testosterone
What are the Special Biological Characteristics of Males
Males have male reproductive structures such as penis, scrotum, and testicles. They produce sperms, the male gametes, which are small and mostly motile. Also, they develop hair on the face at adolescence.
The main sex hormone in males is testosterone, which is responsible for the development of secondary sexual characteristics in males. It is also necessary for the production of sperms in a process known as spermatogenesis, a continuous process from puberty throughout the life.
Males have some amounts of estradiol produced by the conversion of testosterone into it.
What are Special Biological Characteristics of Females
Females only produce eggs, the female gametes, which are comparatively large and non-motile. They have a vagina, a uterus, and ovaries as reproductive structures. They develop a relatively rounded body and enlarged breasts. The two main sex hormones in females are estrogen and progesterone. They are responsible for the development of secondary sexual characteristics in females.
Fertility of females is limited to a certain period of time in their life. Around 500,000 eggs are available by menarche. With the menopause, they stop the release of eggs.
Biological Similarities Between Males and Females
- The fertility process of both males and females is chemically-driven by means of hormones released from the hypothalamus.
- Both males and females have estrogens.
Biological Differences Between Males and Females
Males: Have a penis, scrotum, and testicles
Females: Have a vagina, a uterus, and ovaries
Males: Continuously fertile from puberty due to the continuous production of sperms
Females: Fertile for 12 hours each month until menopause
Males: The main sex hormone is testosterone
Females: The main sex hormones are estrogen and progesterone
Males: Have fewer amounts of estrogen
Females: Have higher amounts of estrogen than males
Males: Have one X and one Y chromosome
Females: Have two X chromosomes
Inheritance of Mitochondrial DNA
Males: Mitochondrial DNA of paternal origin does not pass to the next generation
Females: Mitochondrial DNA from maternal origin passes to the next generation
Size of the Brain
Males: Male brain is bigger
Females: Female brain is smaller than male brain
Males: Forehead is sloped
Females: Forehead is vertical
Males: Have squarer eye sockets with blunt upper borders
Females: Have round eye sockets with sharp upper borders
Males: Face is thinner
Females: Face is broader
Males: Have large veins
Females: Have smaller veins
Males: Fat deposits around their organs
Females: Fat deposits around the abdomen as a ring
Males: Lose the ability to hear high-pitched sounds with age
Females: Lose the ability to hear low-pitched sounds with age
Males: The ability to distinguish between the shades of colors is less
Females: The ability to distinguish between color shades is high
Males: The blood flow is evenly concentrated
Females: The blood flow is concentrated around the pelvic region
Males: Obtain more energy from anaerobic respiration
Females: Obtain more energy from aerobic respiration
Males are continuously fertile after puberty while females are fertile only for several hours per month and they become infertile with menopause. Males have male reproductive organs that produce male gametes called sperms while females have female reproductive organs that produce female gametes called eggs. The main biological differences between males and females are the fertility and the reproductive organs.
1. “Sex Differences in Humans.” Wikipedia, Wikimedia Foundation, 18 Apr. 2018, .
1. “Male anatomy Erect” via
2. “Scheme female reproductive system-en” By CDC, Mysid – Vectorized in Inkscape by User:Mysid from a CDC image (Public Domain) via