Human reproduction follows all the same patterns as for any other mammal.
Humans reproduce sexually so that there is a mix of genetic material within the offspring. Both male and female contribute to the genotype of the offspring.
The phenotype will be determined by all those factors involved in expression of the genes: dominance, recessive, co-dominance etc.
Environmental influences also have an influence on how genes are expressed according to the individual, their physical and emotional environment and, experience.
Human males have testes whilst human females have ovaries. These organs produce and store the respective gametes for the sexes: sperm and eggs (ova).
Testosterone is required for sperm production and oestrogen is required for egg production. There are several types of oestrogen.
- Testosterone is also responsible for Secondary Sexual Characteristics in males
- Oestrogen is also responsible for Secondary Sexual Characteristics in females
There are a number of reproductive hormones common to both sexes
- FSH, Follicle Stimulating Hormone (FSH & LH = Gondaotrophins)
- LH, Leutenising Hormone
- PRL, Prolactin or, Leuteotrophin
There are reproductive hormones generally specific to the sexes:
- Males have testosterone
- Females have oestrogens, progesterones, placental hormones, oxytocin
It is not uncommon though for males to have small levels of oestrogen and females to have small levels of testosterone.
Glands involved in Human Reproduction
- The testes and ovaries
- The placenta is an endocrine gland too
- The Anterior Pituitary gland
- The Hypothalamus
Secretion and / or production of reproductive hormones depend on that portion of the brain complex called the pituitary gland. The pituitary gland in turn depends on the hypothalamus also located within the brain complex.
The diagram of the human brain shown below describes the location of these two specialist areas of the brain.
Image
The Human Brain and Location of the Pituitary Gland and Hypothalamus.
The pituitary gland needs to be described separately as although it is quite small compared to the rest of the brain, it is divided into 2 distinct parts or, lobes.
