The Role of Chromosomes and Hormones

Question 1

What impact to chromosomes have on sex?

Answer 1

-The 23rd pair of chromosomes determine biological sex, XX chromosomes will create a biological female while XY will create a biological male.

Question 2

What is a hormone?

Answer 2

-A chemical substance circulated in the blood that controls and regulates the activity of cells or organs

Question 3

What is testosterone?

Answer 3

-A hormone with naturally higher levels in biological males which has been found to impact secondary sex characteristics as well as various behavioural traits such as aggression.

Question 4

What is oestrogen?

Answer 4

-A hormone with naturally higher levels in biological females which has been found to impact secondary sex characteristics as well as various behavioural traits such as heightened emotionality and irritability during their menstrual cycle, this is often referred to as pre-menstrual syndrome (PMS).

Question 5

What is oxytocin?

Answer 5

• A hormone with naturally higher levels in biological females which increases in levels around childbirth.
• Its purpose is to reduce the stress hormone, cortisol, and to make an individual feel compassion.

Question 6

What evidence is there to support the behavioural effects of hormones?

Answer 6

• Nanne Van de Poll et al (1988) female rats became more aggressive when injected with testosterone.
• Berenbaum and Bailey (2003) females with CAH (congenital adrenal hyperplasia) were seen to exhibit more masculine traits that typical females due to their naturally higher levels of prenatal testosterone.
• Van Goozen et al (1995) found that trans women undergoing HRT (hormone replacement therapy) had decreasing levels of aggression while trans men undergoing HRT had increasing levels of aggression.

Question 7

What evidence is there to support the effect of chromosomes on gender identity?

Answer 7

-David Reimer (case study) was made to live as a female against his will, however his gender identity remained male, despite his experiences telling him that wasn’t the case

Question 8

What evidence is there to criticise the hormone theory?

Answer 8

• Tricker et al (double-blind, 1996) gave 43 males either a weekly injection of testosterone or a placebo injection, there was no difference in aggression between the 2 groups
• The idea of ‘PMS’ has had a questionable impact on society, in that it is often used as an excuse to downplay women’s emotions and invalidate them.