Transcript 9A Inheritance and Selection

9A Inheritance and Selection
Variation
• What is variation?
• What are the two causes of variation?
• What are the two types of variation? Give an
example of each one.
Variation
• Within any group of
individuals there are
many differences. We
call these differences
VARIATION.
• These variations can
occur within a species
Inheritance
There are 2 types of
variations:
Continuous variation –
measured, wide range
e.g. height, weight.
Discontinuous variation –
clear-cut, groups e.g. eye
colour, blood group.
•
Continuous Variation
•You can measure the values
•There is a wide range of values
•The re are inbetween values
Index finger length
5
Frequency
4
3
2
1
0
6 6.1 6.2 6.3 6.4 6.5 6.6 6.7 6.8 6.9 7 7.1 7.2 7.3 7.4 7.5 7.6 7.7 7.8 7.9 8
Finger length (cm)
Discontinuous variation
• This shows clear cut
groups
• Usually you can pick
from a list of
categories
Ear lobes of 11C and 11I
20
15
10
5
0
Attached
Detached
Continuous or discontinuous?
• Height
•Continuous
• Fur colour
•Discontinuous
• Flower colour
•Discontinuous
• Weight
•Continuous
• Shoe size
•Discontinuous
Choose an example of each to
investigate in this class
• Put your results in a table
• Then draw a bar chart
Genetics vs. Environment
• Name 3 characteristics that are caused by
genetics
• Where is this genetic information found?
• Name 3 characteristics that are caused by the
environment
• http://youtu.be/ubq4eu_TDFc
The human
chromosomes
No/widow’s peak
Make your
own
chromosome
No/Mid digit hair
Detached/
Attached ear lobes
Non/Tongue roller
Eye colour
No/Dimples
Sex cells
• What is the male human sex cell?
• How is it adapted to its function?
• What is the female human sex cell?
• How is it adapted to its function?
Sperm
Ovum (plural ova)
• http://youtu.be/-Yg89GY61DE
Selective breeding
• What is selective breeding?
• Where is selective breeding used?
So, Doctor, what is
LHON?
It's a disease of the
mitochondria.
mitochondria. Those
are the things in cells that supply
energy. They're in the
cytoplasm, yes?
That's right! Now
what happens
when an egg
cell is fertilised?
The sperm
nucleus gets into the
egg. Then the egg
nucleus and sperm
nucleus join together
and make your first
complete cell.
Exactly!
But whose
mitochondria
do you get?
mitochondria
Your
come from your mum. You
nucleus
only get a
from your dad.
That's right!
The mitochondria get
copied when your cells divide –
nucleus
just like the
. So
every cell has some. But Maya's
are faulty. That's why she went
blind.
So her
children will go
too?
blind
Yes.
And I'm afraid there is
no
treatment.
But scientists are working on it. Let
me explain – it's all written down
here.
Right, Darcy. I'll let you get
back to your patients. You'll have to tell
Maya and Jake that there is no
solution to their problem.
There might be a treatment in future, but
will it be
too late?
Plan what to say to
Maya and Jake.
Prepare diagrams to
help you explain:
n How 2-parent fertilisation usually happens
n The scientists' idea for 3-parent fertilisation
n Why and how 3-parent fertilisation might help
them in future…if they can wait.
Alien Population: Creation Rules
• 5 main characteristics make up a Geneticon
–
–
–
–
–
Body Shape
Eyes
Nose
Feet or something similar to allow movement
Antennae
• Whether they are Male or female is determined by the
antennae
• Within each of these there are 6 possibilities
6 different genes determining a characteristic
– These are conveniently numbered 1 – 6 for ease of
creation by the role of a die
Geneticon Creation
• Start with Body type
– Roll the die, see which body gene you have. Draw your
Geneticon’s body.
• How will your Geneticon Move?
– Roll the die, see which movement gene you have.
• How fine a looking specimen do you have?
– Roll the die a couple of more times to add eyes and a
nose.
• The final touch is an antenna.
– Remember that this also tells you whether you have a
boy or a girl.
• If you wish you can name your Geneticon.
.
Characteristics Key - Body
1- Round
4 - Square
2 - Triangular
5 - Heart
3 - Blob
6 - Spiked
Characteristics Key - Movement
1- Wings
4 - Flippers
2 - Spring
5 - Feet
3 - Wheels
6 - Ski
Characteristics Key - Eyes
1- Round single
4 - Two on stalks
2 - Round double
5 - Round single with
lashes
3 - Round triple
6 - Round double with
lashes
Characteristics Key - Nose
1- Red blob
4 - Orange blob
2 - Blue blob
5 - Yellow blob
3 - Green blob
6 – Purple blob
Characteristics Key - Antennae
1- Red triangle (girl)
4 - Green triangle (boy)
2 - Red coil (girl)
5 - Green coil (boy)
3 - Red cross (girl)
6 - Green cross (boy)
Picture
Gallery
Alien Population:
Founder Generation
• You have now created your starting population,
your founder generation. They have all grown up
and are now ready to find their ideal partner to
settle down and have their own little Geneticons.
• The Alien dating agency is not that sophisticated.
Pool your Geneticon females and pool your
Geneticon males.
• Now select a random card from each pool. These
are your happy couple.
Making Geneticon Babies
• Take your Geneticon pair.
– What do you think their baby will look like?
– Who’s eyes will it have? Who’s body shape?
– This will be decided by the genes for those
characteristics. (body, eyes, antenna, movement, nose)
– Will it get its Mum’s or Dad’s gene?
• For every characteristic you will flip a coin
– Heads – It will inherit Mum’s gene
– Tails – It will inherit Dad’s gene
• The Geneticons have large families.
– Each couple have a minimum of 4 babies
Family
Mum
Babies
Dad
Baby Competition
The local Mayor of Genesville has decided to hold a
baby competition. He can’t decide whether to make it
the Cutest or Ugliest. So he’s holding both
• You may like to have regional heats within your groups
• Each group can enter one baby into each competition
– Make sure that your babies get entered for the right category!
You never know your cute one might win the Ugly baby
competition!
• Time to vote and announce a winner
• Congratulations or should it be commiserations?
Hybrids
• What is a hybrid?
• Why can’t hybrids reproduce?
Mule (Horse x Donkey)
Tigon (male tiger x female lion)
Liger (male lion x
female tiger)
Zonkey or Zeedonk (Zebra x donkey)
Zorse (Zebra x
horse)
A Zony (Zebra x Pony)
Cama (Camel x Llama)
Leopon (male leopard x female lion)
Yakow (Yak
x Cow)
Beefalo (cow x bison)
Geep (goat x sheep)
Selective breeding vocabulary
• What is a breed?
• What is a variety?
Tomato variation
What features could be the same or different in
different varieties of tomato?
Make a table to show these similarities and
differences.
Flowers
• Why do plants produce flowers?
• Which are the male parts of a flower?
• Which are the female parts?
• Where does fertilisation happen in a plant?
A flower
P
S
A
S
O
O
Cloning
• What is a clone?
• What is asexual reproduction?
• Name some examples of asexual
reproduction.
Sexual and asexual reproduction in
bacteria