Lesson 2
The Biological Explanation for Gender
Lesson 2 – Biological Approach to
Gender
BATs
• Outline the role of chromosomes, gonads and
hormone production in typical gender development
(D)
• Provide evidence to suggest hormones play an
important role in gender development (C+)
http://www.youtube.com/watch?v=JoiVEyCosEE billy elliott
The biological theory of gender
development
The theory is that males and females are simply born different.
Their gender is basically decided at the same time as their
sex – when they are conceived.
The differences between male and female behaviour are
instinctive, and have developed through evolution. Males
are born to provide, fight and protect, whereas females are
born to care for and nurture others.
Human chromosomes
© Boardworks Ltd 2004
X and Y chromosomes
There are two types of sex chromosome with names that
are very easy to remember!
X chromosome
Y chromosome
Females have two X chromosomes,
one from each parent.
Males have one X chromosome
and one Y chromosome.
Which parent does a baby boy
inherit its Y chromosome from?
XX
XY
© Boardworks Ltd 2004
X and Y chromosomes
Does this set of chromosomes come from a male or female?
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
21
19
20
22
23
XY
What kind of sex chromosomes are there in this person’s sex
cells?
© Boardworks Ltd 2004
Chromosomes and sex cells
What happens to the sex chromosomes when sex cells are
formed?
female
body cell
(XX)
meiosis
X
X
X
X
All ova have one X chromosome.
male
body cell
(XY)
meiosis
X
X
Y
Y
Sperm have an X or Y chromosome.
Why is there an equal chance of a baby being a boy or a girl?
© Boardworks Ltd 2004
Gender Game
• In your book draw 6 circles with an X
inside. This represents the egg cell from
the mum
X
Gender Game
Y
Y
X
X
Y
X
Development of the
foetus
• Up to 6 weeks after conception (fertilisation) male and female
foetuses look the same. Gonads (sex organs) no different.
• At 6 weeks Y chromosome ‘switches on’ a hormone called
TESTOSTERONE which makes the gonads develop into
TESTES
• Without this hormone (no Y chromosome) a female’s gonads will
turn into OVARIES
The effects of hormones - males
• Testes produce high levels of TESTOSTERONE – affects brain
after birth.
1. Makes boys more aggressive.
2. Have better maths and spatial skills
The effects of hormones - females
• Ovaries produce high levels of OESTROGEN
1. Makes girls more sensitive
2. Lack of Testosterone gives girls superior verbal skills.
The effects of hormones – evidence
for this theory
• Some female athletes inject themselves with steroids
to improve performance.
• These steroids raise Testosterone levels
Do the
activity
1.4 on p4
• The athletes often report that they felt more
aggressive.
• Men undergoing sex-change operations take drugs
to raise oestrogen levels.
Male or Female?
Male
Female
XY
XX
Testosterone
Oestrogen
Ovaries
Testes
Summary
•The Biological Approach
believes that an individual’s
GENDER is determined at the
same time as their SEX is
determined.
Have you achieved both BATs? How could you
answer the 2nd BAT?
Homework
• Outline how chromosomes, gonads and
hormone production affect gender
development (6 marks) (D)
• (This is basically a summary of what you
have covered today- at least 1 x A5 page )
• Stretch and Challenge - Explain why it it is incorrect
to say that someone has undergone a ‘sex change’.
(B+)
key word
bingo!
Lesson 3
LO - Understand The
Evolutionary Explanation for
Gender
BATs
• Describe basic evolutionary sex differences in
human behaviour. (D)
• Explain the criticisms of the biological theory of
gender development (B)
Another Biological explanation –
Instincts and Evolution
• Human behaviour is INSTINCTIVE to help us
survive and reproduce
• Gender roles are instinctive –
• Psychological differences that help them reproduce
because different hormone levels for males and
females evolved.
• Women more coy – choosier than male, limited
eggs (400)
• Males limitless sperm – less choosy, ‘play the field’
http://www.youtube.com/watch?v=IsSOcwY79ig neanderthal
http://www.youtube.com/watch?v=8_pCzP5AB_Y hunting with
bamboo
http://www.youtube.com/watch?v=1jJgZO-I1kU walking with cavemen
http://www.youtube.com/watch?v=OhAoFeRODQc walking with
cavemen, big brains
Can evolution explain differences in
behaviour?
• Why have females evolved to be more sensitive and caring?
• Why are men more aggressive and competitive?
• Why do men have better visual –spatial skills, but females
communicate better?
Activity 1.5
p5
Evaluating biological theory
How valid are the following points?
 Boys and girls are born the same and we bring them
up differently.
 Males should be more similar and females should be
more similar if it’s to do with biology.
 This theory doesn’t explain different gender roles
across different cultures.
Homework – in next Tues
• Outline 2 criticisms of the Biological theory of
gender development. (4 marks)
• Remember to make 2 points for each criticism to get
2 marks for each …..
•
E.g The biological approach ignores the idea that gender roles might be learnt
(1mark)
• Now give an example or expand on this idea ….
•
E.g boys are rewarded for being tough/girls for being ‘ladylike’ and punished/
humiliated/rejected if they behave like the opposite sex ( 1 mark)