The Role of Chromosomes and Hormones

Question 1

what are chromosomes made from?

Answer 1

DNA

Question 2

what are genes?

Answer 2

short sections of DNA that determine the characteristics of a living thing

Question 3

how many chromosomes and how many pair of chromosomes are there in the human body?

Answer 3

• 46 chromosomes
• 23 pairs

Question 4

what pair determines biological sex?

Answer 4

the 23rd pair determines biological sex

Question 5

what do egg cells have?

Answer 5

egg cells are produced by a human ovary have an X chromosome

Question 6

what chromosome do sperm cells carry?

Answer 6

• an X or Y chromosome

Question 7

when is the baby’s sex determined?

Answer 7

sperm that fertilises the egg cell

Question 8

when is the baby female?

Answer 8

if the fertilising sperm carries an X chromosome

Question 9

when is the baby male?

Answer 9

if the fertilising sperm carries a Y chromosome

Question 10

what does a Y chromosome carry?

Answer 10

• a gene called the sex-determining region Y
• SRY

Question 11

what does the SRY gene cause?

Answer 11

• causes the testes to develop in an XY embryo
• these produce androgens, male sex hormones

Question 12

what do chromosomes determine?

Answer 12

a person’s sex

Question 13

how does gender development come about?

Answer 13

• through the influence of hormones

Question 14

prenatally in the womb where do hormones act?

Answer 14

hormones act upon brain development and cause development of the reproductive organs

Question 15

what happens at puberty during adolescence?

Answer 15

a burst of hormonal activity triggers the development of secondary sexual characteristics such as pubic hair

Question 16

what are the similarities and differences in hormones in males and females?

Answer 16

males and females produce the same hormones in different concetrations

Question 17

what is testosterone and what does it control?

Answer 17

• male hormone, present in women in small quantities
• controls the development of male sex organs during foetal development

Question 18

what happens if a genetic male produces no testosterone during foetal development?

Answer 18

no male sex organs appear

Question 19

according to the evolutionary explanation high levels of testosterone…

Answer 19

are linked to aggression as it is adaptive
- aggression towards rivals allows males to compete for the opportunity to mate with a fertile female
- women tend children means that men are more likely to take the hunter role and success would be enhanced by aggressiveness

Question 20

what are the physical changes with testosterone?

Answer 20

male sex organs(testes)

Question 21

what are the psychological changes with testosterone?

Answer 21

aggression, competitiveness and spatial skills

Question 22

what is oestrogen?

Answer 22

female hormone

Question 23

what are the physical changes of oestrogen?

Answer 23

• female sexual characteristics and menstruation

Question 24

what are the psychological changes of oestrogen?

Answer 24

• heightened emotions
• irritability
• premenstrual syndrome (PMS)

Question 25

when has PMS been used to successfully defend cases?

Answer 25

• shoplifting
• and even murder

Question 26

what is oxytocin?

Answer 26

• women produce more oxytocin than men, specifically during labour and childbirth

Question 27

what are the physical changes with oxytocin?

Answer 27

• stimulates lactation
• reduces stress hormone (cortisol)

Question 28

what are the psychological changes with oxytocin?

Answer 28

• known as the love hormone
• facilitates bonding