Transcript 3.1a Mutations

Starter:
What do you know about DNA?
Think 
Mutations
Learning Intentions:
To know what a mutation is.
To know that a mutation can cause an
advantage, a disadvantage or be neutral.
Success Criteria:
Complete a summary showing examples of
mutations.
Starter:
What do you know about DNA?
Think  Pair
What do you know about DNA?  Share
What is a genetic mutation?
The X-men are described as mutants, why?
Mutations
• A mutation is an unplanned, random
change to the genetic code.
• These changes can give the organism an
advantage, a disadvantage or be neutral.
• Twig on Glow: Mutations definition
Mutations
We will look at some examples of mutations:
•
•
•
•
Peppered moths
Sickle cell anaemia
Bacteria mutations and antibiotic resistance
Albino mutations
Do you know anything about
any of these examples
already?
Peppered Moths
• Peppered Moths
can be found in two
colours- black and
white forms.
• In unpolluted areas, where lichen grows
on trees. The white form are
camouflaged. More of the black form
are eaten by predators.
• In polluted areas
trees become
blackened by soot
and pollution. Lichen
don’t grow. The
black form are
camouflaged. More
white form are
eaten by predators.
Sickle Cell Anaemia
• Sickle Cell Anaemia is an inherited
disease of the blood, which is the result
of a mutation.
Sickle Cell Anaemia
• People with this disease have sickle
shaped red blood cells which reduces
the amount of oxygen they can carry.
Sickle Cell Anaemia
• In most populations it is rare to
have Sickle Cell Anaemia but in
some parts of Africa 40% of the
population are sufferers.
• This is because those with sickle
cell have some resistance to
malaria. This is because their
“sickled” red blood cells carry
fewer of the Plasmodium organisms
that cause Malaria. So it is
advantageous for some people to
have the mutation.
Sickle cell anaemia can be an
advantage and a disadvantage to
sufferers.
Sickle Cell Anaemia
Sickle cell anaemia can be an advantage
and a disadvantage to sufferers.
This is because it can provide
protection against malaria but can also
leave sufferers with lower blood oxygen
levels.
Albino Mutations
Meet Pinky, a bottlenose dolphin calf.
Pinky was discovered in an inland lake in Louisiana, and has become
such an attraction that conservationists have warned tourists to
leave it alone.
Pinky's colour comes from the fact that he is an albino, well
demonstrated by his reddish eyes.
According to marine biologist Dagmar Fertl, this is
only the fourteenth spotting anywhere in the world
(the first coming in 1962).
Biologists think that, in addition to the rarity of their
birth, the scarcity of albino bottlenose dolphins might
be due to their having poor eyesight, increased
sensitivity to sunlight, and a coloration that provides
poor camouflaging, factors which could significantly
decrease their chances of reaching maturity, mating
and passing on the albino gene.
The Amazon River Dolphin,
• This is the largest of the
freshwater dolphins, and like
all freshwater dolphins it is
endangered because of
hunting, human pressures, and
degradation of habitat.
• Its most amazing
characteristic is its colour,
which ranges from a grey
soft, rosy pink to a vivid,
almost shocking pink.
Bacteria resistance to disease
1. Can you remember what a bacteria cell
looks like?
2. In pairs try to draw it on a show me board.
3. Can you label it?
How antibiotics work.
• Antibiotics work in a
variety of ways to
destroy the bacteria.
• E.g penicillin inhibits
the synthesis of the
cell wall.
• Streptomycin inhibits
protein production.
Antibiotic Research Challenge
Homework task due in one week
Your task is to produce an A3 poster presentation on
antibiotic resistance:
You must include…
 Who discovered the first antibiotic, when and how was this
discovery made.
 How antibiotics work.
 The names of three antibiotics and the diseases they treat.
Include the signs and symptoms of these diseases.
 What is meant by the term “antibiotic resistance”. Name at
least two diseases caused by bacteria resistant to
antibiotics. Include the signs and symptoms of these
diseases.
You could include…
 A description of the problems caused by having too many
bacteria resistant to antibiotics. A description of how world
organisations are planning to tackle this problem.
Bacteria Resistant to Antibiotics
You must complete…
Resistant bacteria activity and worksheet.
You should complete…
Watch the following clip, make notes and discuss:
BBC Learning Zone Class Clip: The future of antibiotics
You could complete…
Read and discuss the following news articles:
BBC News story: antibiotic resistance
Daily Mail news article about 'superbugs'
Extension task:
Attack of the hyperbugs:
Literacy
Read the Daily Mail news article from the last task and answer the
following questions:
1.
2.
3.
4.
5.
6.
7.
How many patient deaths are caused by drug resistant bacteria?
Who is warning that we must take action against these super bugs?
In your own words describe how bacteria become resistant to
drugs.
Why are those already in hospital at high risk?
Pick one resistant bacteria, describe where its found and how it
spreads.
How are organisations planning to reduce deaths due to resistant
antibiotics? What countries and organisations should be involved?
Do you think the Daily Mail is a good source? Where did they get
their information from- is this a valid source?
http://www.dailymail.co.uk/health/article-2012905/Attack-hyperbugs-Wevesuperbugs-strains-resilient-drugs-kill-them.html
Mutations Summary
Species
Mutation
Human
Sickle cell
anaemia
Amazon
River
Dolphin
Skin colourAlbino
Bacteria
Resistant to
antibiotics
Peppered
Moths
Black moth in
unpolluted area
Advantage or
Disadvantage or
Neutral
Explanation
Mutations
Learning Intentions:
To know what a mutation is.
To know that a mutation can cause an
advantage, a disadvantage or be neutral.
Success Criteria:
Complete a summary showing examples of
mutations.
Starter:
Can you explain one example
of a mutation to your partner?
Extra: Can you explain if your
example is neutral, advantageous or
disadvantageous?
Mutations
Learning Intentions:
To know that mutations are spontaneous and
are the only source of new alleles.
To know environmental factors which can
increase the rate of mutations.
Success Criteria:
Complete a report on mutations and
mutagenic agents.
What causes genetic
mutations?
Mutagenic agents
• Mutations are spontaneous and are the
only way new alleles can be created.
• Environmental factors such as radiation
and chemicals, can increase the rate of
mutation.
IDL: Physics
Radiation
Radiation
• Radiation can increase the rates on
mutation.
• X-rays and gamma rays are known to be
harmful and increase the risk of
mutation.
Marie Curie
• First women to win
Nobel Prize. Only
person to win Nobel
Prizes for more than
one science (Physics
and Chemistry).
• She died in 1934 from aplastic
anemia believed to have been
contracted from her long-term
exposure to radiation.[
• She had carried test tubes
containing radioactive isotopes in
her pocket and stored them in
her desk drawer, remarking on
the “faint light” that the
substances gave off in the dark.
• Although her many decades of
exposure to radiation caused
chronic illnesses (including near
blindness due to cataracts) and
ultimately her death, she never
really acknowledged the health
risks of radiation exposure.
Radiation risks
Clip about deaths of researchers at Manchester
University from back ground radiation:
• http://www.bbc.co.uk/learningzone/clips/wasradiation-responsible-for-nuclear-scientistsdeaths/5970.html
Radiation from solar flares:
• http://www.bbc.co.uk/learningzone/clips/theeffects-of-space-travel-on-humans/9836.html
Chemical Exposure
• Exposure to certain chemicals can
increase the risk of mutations.
• Some chemicals change or damage the
DNA of a cell, which can increase the
frequency of mutations.
• Many mutations cause cancer and these
chemicals are called carcinogens.
Common carcinogens.
Inhaled asbestos.
• Tobacco smoke.
Mutations Report
You must include:
A description of what a mutation is.
A description of two types of mutagenic agent (giving specific
names of chemicals or radiation).
A description of how people or animals can become exposed to
these dangers.
You should include:
An example of a mutation cause by a mutagenic agent.
Explain if the mutation is neutral, advantageous or
disadvantageous to the organism.
You could include:
A description of how governments limit the risks of people
being exposed to mutagenic agents.
A full list of references.
You can create a leaflet, report or power point presentation.
Mutations
Learning Intentions:
To know that mutations are spontaneous and
are the only source of new alleles.
To know environmental factors which can
increase the rate of mutations.
Success Criteria:
Complete a report on mutations and
mutagenic agents.
Interactive website
http://www.abpischools.org.uk/page/modu
les/genome/dna5.cfm?age=Age Range 1416&subject=Biology