Male Repro Physiology 2 Flashcards
What are the 2 main function of the testes?
Sperm Production
Testosterone
what is the function of testosterone?
Male secondary sexual characteristics
Controls spermatogenesis
What does the hypothalamus produce
GnRH
What does GnRH cause the release of?
Gonadotropins
What 2 gonadotrophins are produced and from where?
FSH and LH
From the anterior pituitary
What is FSH responsible for?
Sperm production Spermatogenesis
What s LH responsible for?
Controls Leydig cells producing testosterone
What happens when there is too much testosterone?
Negative signal to hypothalamus and anterior pituitary
What is the function of inhibin?
Negative signal to anterior pituitary
How long is the average cycle spermatogenesis?
64 days
When does spermatogenesis start and end?
Starts at puberty
It is life-long
What is sperm produced from?
Primordial germ cell
What are the 2 stages of sperm development?
Spermatocytogenesis
spermiogenesis
What is spermatocytogenesis?
Clonal expansion and maturation through mitotic and meiotic division
What is spermiogenesis?
Maturation of spermatids into functional sperm cells
How many divisions occur in spermatocytogenesis and what type of division?
One mitotic division
two meiotic divisions
What are the 2 type of factors that can affect spermatogenesis?
Environmental
Medical
What are the 2 type of environmental factors?
Maternal
Paternal
Are maternal factors reversible or irreversible?
Irreversible
Are paternal factors reversible or irreversible?
Reversible
What are paternal factors?
Smoking
Obesity
Chemical exposure
What are the 2 types of medical problems?
Pre-testicular
Testicular
What are pretesticular problems?
Problem with hormonal control
What are testicular problems?
Problem at the site of production
Examples of pretesticular problems
Functional-weight Intracranial tumour, cysts Prolactinoma Medications- Opiates, steroids Genetic-Kallmann’s syndrome (deficiency of GnRH
Examples of testicular problems
Surgery-orchidectomy STI Mumps Trauma or torsion Radio or chemo Genetic-Kleinfelter’s