human

2. Presented by: Maimoona Ambreen
Tayyaba Jameel
Presented to: Mam Zaib un Nisa Asif
Department Life Sciences
Islamia university Bahawalpur

3.  Sex linkage in human
 Colour blindness
 Causes of colour blindness
 Types of colour blindness
 Examples of colour blindness
 Transformaation of colour blindness
 Test cross
 Symptoms
 Detection
 effects

4. Sex linkage is
the phenotypic expression of
an allele related to
the allosome (sex chromosome)
of the individual

5. • Twenty genes in human are
sex linked
• Red green colour blindness
and hemo philia
• Both these diseases are sex
linked recessive traits

7. Colour blindness is a
condition in which
individuals have difficulty
in distinguishing red from
green

8. E.B Wilson firstly discovered facts about hereditary
colour blindness
It is genetic disease and inherited from mother to
child
Genes for colour blindness present on X-chromosome
Colour blindness occurs in about 8% males and only
0.5% in females
Some people become colour blind due to other
diseases like diabetes and medication and multiple
sclerosis

9. Protanolay
Which reduce the sensitivity to red
colour
Deuteranomaly
Which reduce sensitivity to green colour
Tritanomaly
Which reduce sensitivity to blue colour

13. Deuteranopia- Green cone is blind
Deuteranomaly- Green cone is weak
Protanopia- Red cone is blind
Protanomaly- Red cone is weak
Tritanopia- Blue cone is blind
Tritanomaly- Blue cone is weak

14.  Why colour blindness is occure more in males instead of
females
 Father transfer his x chromosome to all daughters and
mother transfer her x-chromosome
 Son will be colour blind and daughter will be normal if
his mother is carrier and father is normal
 Colour blind daughter will be produce only when his
father is colour blind and mother is carrier or colour
blind
 Since such marriages are very rare

15. If mother is
normal and father
is colour blind.
Then son will be
normal and
daughter will be
carrier.

16. If motheris carrier and
father is colour blind
50 percent chances
daughters m
ay be colour blind or
carrier
50 percent chances
that son will be normal
or colour blind

17. If mother is colour
blind and father is
normal
All sons will be
colour blind and all
daughters will be
carriers

18. Symptoms of color blindness could range from mild
to severe. Examples would be difficult distinguishing
between colors, or inability to see shades of the same
color. Rapid eye movement could occur in rare causes, and
Sensitivity of bright light. They could also suffer from
having trouble seeing the brightness of color in the usual
way. Inability to tell the differences between shades of the
same or similar colors. Particularly red and green or blue
and yellow.

19. It can be detected by
using special charts
made up of coloured
dots
These dots are so
arranged that coloured
blind person can see a
defferent pattern

20. Effects of color blindness are difficult distinguishing color
such as blue and yellow or red and green. Problems can
arise in some simple activities such as choosing and
preparing food, gardening, sport, driving a car and
selecting clothing. Trouble can arise by not being able to
pick up a change in someone’s mood or a change in the
color of their face, or in some parents cases, notice their
child getting sunburn.
Food can look repulsive or unappealing due to the change
of the color a colorblind person can see.