Sex Differences Flashcards
What are sex differences in behavior due to?
gonadal hormones
What was the result of the removal of gonads in juvenile roosters?
reduction in male-associated behaviors such as aggression
could be reversed by implanting testes into body cavity
How do females and males differ in chromosomal content?
-females have 2 copies of all genes on X chromosme
What is the significance in the difference of chromosomal context?
-some genes on X chromosome may be more highly expressed in females
T/F Y chromosomes have some genes not found on X chromosome?
True
Which sex bird has song nucleus?
present only in males (sing to court)
What is the result of a 1/2 male 1/2 female bird?
- both sides exposed to gonadal hormone
- male side has bigger song nucleus
what is SRY?
-sex region on Y determines development of gonads
Transgenic animal chromosomal make up
XX+SRY male gonads
XY-SRY female gonads
What plays a role outside gonads in sex determination?
sex chromosomes
What is the evidence of sex chromosomes playing a role outside gonads in sex determination?
- all animal except XX are aggressive (male-like behavior)
- male gonads or male chromosomes produce phenotype
What hormone is involved in pair bonding?
-vasopressin
What is vasopressin?
- peptide hormone
- controls reabsorption of molecules in tubules of kidneys (concentrates urine)
What releases vasopressin?
posterior pituitary gland (also can be synthesized and released directly into brain)
When is vasopressin released?
-during sexual activity/affiliative activity
