Sex And The Brain Flashcards
Define sex
Biological state of being male or female, and is determined by chromosomes, hormones and body anatomy.
Define gender
Set of behaviours and attributes a culture associated with men and women.
Define gender identity
Our perception of our own gender
How many genes are in the X and Y chromosome?
X - 800 genes
Y - 50 genes
What does the sex-determining region of the Y chromosome (SRY) code for?
Protein called testis-determining factor (TDF)
Where is the SRY gene located?
Short arm of Y chromosome
Define turner syndrome
Partial or complete absence of one X chromosome in a female (XO genotype)
What are the characteristics of turner syndrome?
Short stature
Receding jaw
Webbed neck
Visuospatial and memory difficulties
Define Klinefelter syndrome
Extra X chromosome
How do the gonads determine sex?
During first 6 weeks of pregnancy, no changes but contains the Wolffian duct and Müllerian duct
Male - Wolffian duct develops into male internal reproductive system due to release of testosterone. Mullerian-inhibiting factor also produced to inhibit female organs.
Female - Müllerian duct develops and Wolffian degenerates
Name male hormones
Androgens
Name female hormones
Estrogens
What is estradiol synthesised from?
Testosterone using aromatase
What is the primarily responsibility of the testes?
Release of androgens
What is the principal female hormone?
Estradiol and progesterone - secreted by ovaries
Name the two hormones secreted by the pituitary gland for normal sexual development?
Luteinizing hormone (LH)
Follicle-stimulating hormone (FSH)
Describe role of gonadotropin-releasing hormone (GnRH)
Causes release of LH and FSH
What does gonadotrophins stimulate in males?
LH stimulates the testes to produce testosterone
FSH matures sperm cells
What does gonadotrophins stimulate in females?
LH and FSH cause the secretion of estrogen from the ovaries - menstrual cycle
State the sexual response cycle
Arousal
Plateau
Orgasm
Resolution
What is the pathway from genitals to brain
Axons from mechanoreceptors in the pen is and clitoris collect in the dorsal roots of the sacral spinal cord. They then send branches into the dorsal horns of the cord and into the dorsal columns through which they project toward the brain
Engorgement and erection are primarily controlled by what?
Axons in the parasympathetic division of the ANS