Examiners:+
+
Hanspeter)Stucker,)Michael)Schwaller,)Tom)Lütscher,)Erica)Colangelo)
)
Full+Name:+_______________________________________+
+Class:++_____________+
Matura+Examination+2013++
+
E+N+G+L+I+S+H++
+
“Do what you can, with what you have,
where you are.”
Theodore Roosevelt
Advance+Information:++
a. The)written)Matura)examination)in)English)consists)of)four+main+sections:))
Section)I:)Listening+(Total)credits:)13))
1. “Reproduction+and+Cloning”++
2. “Cloning+and+Genetic+Modification”++
Section)II:+Use+of+English+(Total)credits:)64)))
1.
2.
3.
4.
Synonyms++
Antonyms+
Word+formation+
Open+Cloze+
Section)III:+Reading+Comprehension+(Total)credits:)24)+
1. Short+answer+questions++
Section)IV:+Writing,+350K400)words)(The)mark)achieved)in)this)part)will)make)up)50%)of)the)final)mark)))
b. Time+management:)The)total)time)is)240)minutes.)We)recommend)spending)120)minutes)on)Sections)I)K)III,)
and)120)minutes)on)Section)IV.))
c. Write)legibly)and)unambiguously.)
d. Use+of+dictionary:)You)will)be)allowed)to)use)a)monolingual)dictionary)after)having)handed)in)Section)IKIII.))
e. The)examination)is)based)on)Natasha)Walter’s)article)“Can)Science)Save)Us)from)Ourselves?”)as)published)
in)The$Independent)in)2002.))
We)wish)you)the)best)of)luck!++
)
Full+Name:+_______________________________________+
+Class:++_____________+
Section)I:+Listening.+(Total)credits:)13)))
Task:)You)will)hear)an)interview)in)two)parts)with)a)woman)called)Kat)Arney,)an)expert)on)reproduction)and)
cloning.)For)each)part,)circle)the)answer)(A,)B)or)C))that)fits)best)according)to)what)you)hear.))
Before)the)listening)starts,)you)will)have)1.5)minutes)to)consider)the)answers)of)both)parts.)You)will)then)hear)
each)part)of)the)interview)twice,)with)a)oneKminute)pause)between)part)1)and)part)2.))
Your)answer)sheet)for)this)part)of)the)examination)will)be)collected)5)minutes)after)the)listening)is)completed.))
Part+One:+“Reproduction)and)Cloning”++
1. Genes...$$
A. are)what)we)share)with)our)parents,)which)makes)us)look)similar)to)them.))
B. is)another)expression)used)for)our)DNA.))
C. are)a)set)of)particular)proteins.))
2. Kat$Arney$explains$that...$$
A. there)are)3,600)genes)in)the)four)pairs)of)chromosomes)of)fruit)flies.))
B. fruit)flies)carry)around)13,600)genes.))
C. there)are)six)pairs)of)chromosomes)to)carry)the)genes)of)fruit)flies.))
3. Which$statement$about$genes$is$incorrect?$$
A. Each)gene)gives)instructions)for)one)particular)protein.)
B. Genes)are)packed)up)in)the)nucleus)of)cells)in)the)form)of)chromosomes.)
C. Humans)have)about)13,000)genes.)
4. What$exactly$happens$at$the$moment$of$fertilization?$
A. Mixing)of)two)diploid)sets)of)chromosomes.)
B. Reproduction)of)gametes)(specialized)sex)cells))containing)half)the)chromosomes.)
C. The)fusion)of)chromosomes.))
5. You$talk$of$clones$when$…$
A. animals)or)plants)are)genetically)modified)so)that)the)offspring)looks)exactly)like)their)parent.))
B. there)is)a)sexual)reproduction.)
C. there)is)no)mixing)of)the)genes.)
6. In$the$plant$world$the$phenomenon$of$clones$is$quite$common.$For$example,$...$$
A. daffodils)reproduce)by)making)little)side)branches.)
B. potatoes)grow)underground)storage)organs.)
C. sea)anemones)produce)runners)which)creep)along)the)ground.))
)
Part+Two:+“Cloning)and)Genetic)Modification”++
7. According$to$Kat$Arney,$the$simplest$approach$to$clone$plants$is...$$
A. a)process)called)tissue)culture,)where)tiny)pieces)of)plants)grow)into)little)plantlets.))
B. cover)the)stem)in)plastic)to)encourage)new)roots)to)grow.))
C. stick)a)part)of)a)plant)into)a)pot.))
8. The$two$ways$of$animal$cloning$are...$$
A. embryo)transplants)and)fertilization)of)an)embryo.)
B. embryo)transplants)and)nuclear)transfer.)
C. fertilization)of)an)embryo)and)nuclear)transfer.)
9. In$nuclear$transfer$you...$$
A. inject)DNA)from)an)animal)you)want)to)clone)into)the)egg)of)a)foster)mother.))
B. transplant)separated)cells)from)an)embryo)back)into)a)host)mother.))
C. use)the)DNA)to)activate)the)nucleus)so)that)it)grows)into)a)baby.))
10. The$first$successful$clone...$$
A. was)achieved)by)a)team)of)scientists)around))Ian)Wilmut.))
B. was)achieved)through)the)fusion)of)a)sheep’s)cell)and)another’s)egg.))
C. was)the)sheep)Dolly,)which)died)in)1996.))
11. GM$is$also$known$as...$$
A. genetic)interfering.))
B. genetic)engineering.))
C. genetic)cloning.))
12. Kat$Arney$mentions$medicine$to$show$how...$$
A. genetically)modified)bacteria)can)be)used)to)produce)human)insulin)for)diabetic)people.))
B. genetically)modified)bacteria)is)gained)from)essential)human)proteins)to)cure)diabetes.))
C. nonKallergic)insulin)for)diabetic)people)can)be)produced)by)genetically)modified)pigs.))
13. Among$the$benefits$of$GM$are,$for$example,$...$$
A. plants)that)light)up)to)tell)you)when)they)need)watering.))
B. genetically)modified)crops)which)are)resistant)to)weed)killers.))
C. a)sheep’s)protein)that)has)been)invented)in)order)to)treat)people)with)cystic)fibrosis.))
)
)
Can Science Save Us from Ourselves?
From: Natasha Walter, ‘Science Can’t Save Us from Ourselves’, The Independent, 28 February, 2002.
A decision taken yesterday in the venerable1 atmosphere of the House of Lords2 would once have sounded
as if it had been plucked straight from an Aldous Huxley3 novel or a Stanley Kubrick4 film. The Lords in
their wisdom decided that scientists should be able to dabble in cells taken from cloned human embryos.
But given the current rash of tales about ‘designer’ babies and genetic manipulation, such a decision has
5
almost lost its potential to surprise us. Over the past few days we’ve been treated to the story that one baby
will be selected so that its genetic material can save its brother and to the tale that another baby has been
born after being selected to be free of the gene that predisposed her mother to Alzheimer’s disease.
So much has been talked about designer babies that the public’s perception of what is now possible in
genetic science has already way outrun reality. Many people probably believe that if they were given their
10
way, scientists could already clone dozens of dinky copies of themselves, grow embryos to term in plastic
wombs outside women’s bodies, manipulate the eye-colour or piano-playing ability of foetuses and,
altogether, provide the perfect à la carte baby service.
Couples who can’t conceive naturally are often shocked to realise that doctors cannot just wave a wand
and create a baby for them and that fertility treatments still have high failure rates. When you look at the
15
reality of the designer baby stories, what is in fact going on is a lot cruder than the science-fiction dreams.
But all the talk about designer babies means that the decision taken by the House of Lords select committee
to allow limited research using cloned human embryos hardly feels revolutionary.
This move promises to put Britain in the forefront of stem-cell research, and most people in this country
are likely to welcome it. After all, manipulating the very structure of life is exactly what we have come to
20
expect from scientists. People in the Western world are beginning to believe that life should be completely
controllable. They are beginning to believe that all babies should be perfect: that nobody should suffer from
diseases caused by genetic dysfunction; that research using the cells of embryos will be used to combat
disabilities and intractable diseases such as Parkinson’s and Alzheimer’s; that old age itself should one day
pretty soon – and hopefully in time for our retirement – be curable.
And why not? If our culture didn’t have this impatient attitude to nature, this arrogant belief that
25
physical and even mental illnesses can always be conquered, where would we be? Still thinking that 40 was
a ripe old age and still having a dozen children in the hope that one would survive until adulthood, no
doubt. […]
Certainly we in the West can dream of perfect control over our health – we can listen to the tales of
30
dazzling experiments resulting in cloned animals and the possibility of break-throughs that might, one day,
make paraplegics5 walk again and give brain connections back to Ronald Reagan. We can fantasise that we
might become a perfect race, each of us taken through a life of absolutely predictable health from a
managed birth to a far-off, pain-free trip to the grave.
)))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))
1
venerable: deserving respect because it is important
2 House
of Lords: one of the chambers of the Parliament of the United Kingdom; its members are not elected by the people
of the country but are appointed by the government. The Lords work with the House of Commons to make laws, check the
actions of the government and provide independent expertise relating to politics, science, technology, economics, etc.
3 Aldous
4 Stanley
Huxley (1894-1963): English writer, best known for his dystopian science-fiction novel Brave New World.
Kubrick (1928-1999): American film director, producer of the groundbreaking science-fiction film 2001: A Space
Odyssey.
5 paraplegics:
people suffering from paraplegia; they have no control or feeling in their legs and lower body. )
)
If you buy into that dream, the Lord’s decision yesterday to allow research using cells from cloned
35
embryos is just part and parcel of a great story of progress. […] As Robert Lanza, the vice-president of
medical and scientific development at ACT6, said after his company cloned the first human embryo in the
US last year. ‘Our intention is not to create cloned human beings, but rather to make life-saving therapies
for a wide range of human disease conditions, including diabetes, strokes, cancer, Aids.’ How can one argue
with that?
One can’t. But look again at the diseases that he said that cloned-embryo cell research is now expected to
40
deal with: diabetes, strokes, cancer, Aids. And then look at some of the other health stories to have hit the
headlines.
The story that, for instance, one in four five-year-old girls is showing early signs of diabetes due to the
increase in childhood obesity. Or that a form of diabetes, previously known to affect only overweight adults,
45
is now being identified in children as young as 13 because of their poor diets and lack of exercise. Or that
the incidence of sexually transmitted diseases, including HIV, is rising steeply because young people refuse
to wear condoms. Or that deaths from alcohol-related car crashes rose sharply last year. Or that young girls
and boys are becoming increasingly heavy drinkers. Or that smoking has increased among people aged
from 16 to 19.
This is where the dream of total control falls down – not in the achievement of scientists, but in the
50
messy reality of our lives. What do we really want? We may think we want perfect health, a life lived in
absolute control. And when we make rational choices for ourselves or for others, of course that’s what we
choose. But then we pour another glass to take the evening into a lovely haze, we strap ourselves into steel
cages and roar around the country at 90 miles an hour, or we ride a wave of urgent passion without even
55
remembering that packet of condoms sitting in the bathroom cabinet. Of course we do!
For all the trendy talk of holistic health care7, what most people in the West want is the opposite – they
want to eat what they like and do what they like and still live as long as they want. That’s why the reality of
our lives so often falls so far short of the dreams of both science and science fiction. Neither takes account
of the messy irrationality of human desires – desires that seem to get even more messy and irrational, as
60
our theoretical ability to control our lives increases.
Nor, of course, does the dream of total control take any account of the unspeakable inequalities in the
world. Because it beggars belief8 that, while we have worked out how to save babies in America from her
own genetic heritage, we still haven’t worked out how to save babies in other countries from dying of
drinking dirty water.
That’s not to say that the scientists are on the wrong track. Surely they are just doing what scientists do –
65
expanding our knowledge and spelling out the secrets of life, day by day.
But perhaps we should put their glittering achievements into perspective. Because, although scientists
might one day be able to save us even from our genes, they still won’t be able to save us from ourselves.
)
)))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))
6 ACT:
Advanced Cell Technology )
7 holistic
8 beggar
+
health care: treating the whole person rather than just the symptoms of a disease)
belief: to be too extreme, shocking, etc. to believe )
)
Section)II:+Use+of+English.+(Total)credits)64)))
1. Synonyms.+Give)a)word)or)short)phrase)with)the)same)meaning)to)replace)the)following)words.)) 10+credits)
a.
rash)of)(line 4))
________________________________________))
b.
potential)(5))
________________________________________))
c.
hardly)feels)(17))
________________________________________))
d.
forefront)(18)
________________________________________))
e.
likely)(19))
________________________________________))
f.
conquered)(26)
________________________________________))
g.
dazzling)(30))
________________________________________))
h.
resulting)in)(30)
________________________________________))
i.
buy)into)(34))
________________________________________))
j.
lack)(45) )
________________________________________))
2. Antonyms.+Give)a)word)or)short)phrase)with)the)opposite)meaning)to)replace)the)following)words.))
+
4+credits+
a.
increasingly)(48))
________________________________________))
b.
are)on)the)wrong)track)(65)))
________________________________________))
c.
expanding)(66))
________________________________________))
d.
glittering)(67))
________________________________________))
3. Word+formation.+Use)the)appropriate)word)from)the)same)word)family)(i.e.)derived)from)the)same)root)
word))as)the)word)indicated)to)complete)the)sentences)below.++
15+credits+
a. wisdom)(3))
She)____________________________________)decided)to)tell)him)the)truth.)
b. manipulation)(4))
He)is)extremely)____________________________________,)so)don’t)let)him)persuade)you.)
c. perception)(8))
She)did)not)____________________________________)herself)as)disabled.)
d. provide)(12))
The)government)is)responsible)for)the)____________________________________)of)health)care.)
e. fertility)(14))
The)treatment)has)been)tested)on)healthy,)____________________________________)women.)
1)
)
f.
curable)(24))
‘Will)you)be)able)to)____________________________________)him,)doctor?’))
g. predictable)(32))
Many)young)offenders)commit)further)crimes)with)alarming)____________________________________.)
h. transmitted)(46))
There)is)a)____________________________________)of)the)disease)in)this)country.)
i.
achievement)(50))
All)you)____________________________________)is)to)upset)my)parents.)
j.
choose)(53))
You)will)have)to)make)a)___________________________________)between)what)is)right)and)what)is)easy.)
k. urgent)(54))
There)was)a)note)of)____________________________________)in)his)voice.)
l.
irrationality+(59))
He)sometimes)behaves)____________________________________.)
m. ability)(60))
I)didn’t)feel)____________________________________)to)disagree)with)him.)
n. heritage+(63))
He)will)____________________________________)a)fortune)from)his)father.)
o. save)(63))
Nobody)is)____________________________________)from)suspicion)at)the)moment.)
2)
)
4. Open+cloze.+Complete)the)text)below)by)writing)one)word)in)each)space.++
15+credits+
We)humans)pride)ourselves)on)(a.)+________________________________)the)masters)of)the)earth,)but)
modern)man)(b.))_________________________________)only)been)around)for)200,000))years)of)the)planet’s)
fourKandKaKhalf)billion)year)history.)And)(c.))_________________________________)to)many)scientists,)the)
longKterm)outlook)for)us)isn’t)rosy.)(d.))_________________________________)our)tendency)to)get)rid)of)each)
other)doesn’t)finish)us)(e.))_________________________________,)then)our)propensity)for)destroying)the)
environment)could.)So)what)might)replace)the)human)race?)(f.))_________________________________)the)
aid)of)the)latest)computer)graphics,)experts)believe)that)some)(g.))_________________________________)the)
fantastic)creatures)could)emerge)as)our)inheritors.)(h.))_________________________________)creatures)
might)look)like)something)(i.)+_________________________________)of)a)scienceKfiction)film,)but)experts)
claim)there)are)(j.))_________________________________)than)enough)clues)to)predict)what)future)
inhabitants)of)the)earth)might)look)(k.))_________________________________.)We)know)the)continents)are)
moving)and)that)the)Atlantic)is)widening)(l.))_________________________________)about)the)rate)our)
fingernails)grow.)So)with)the)right)computer)modelling,)we)can)calculate)(m.)+___________________________)
the)continents)will)end)up.)Ecologists)can)then)predict)what)habitats)might)exist,)and))
(n.))_________________________________)types)of)animals)that)might)live)in)them.)The)good)news)is)that)
this)species’)upheaval)is)about)three)million)years)away,)so)there)is)(o.))________________________________)
need)for)us)to)lose)sleep)over)it)just)yet!)
(Adapted)from:)Gude,)Kathy)and)Mary)Stephens:)CAE$Result.$Student’s$Book.$Oxford:)OUP,)2008,)53.))
5. Sentence+transformation.+Using)the)word(s))given)in)bold,)complete)the)sentences)so)that)the)second)
sentence)has)the)same)meaning)as)the)first.)Do)not)change)the)word(s))given.++
20+credits+
a. The)Lords)in)their)wisdom)decided)that)scientists)should)be)able)to)dabble)in)cells)...)(lines 2-3) )
decision+)
A$wise$$__________________________________________________________________________________$
b. ...)given)the)current)rash)of)tales)about)‘designer’)babies)and)genetic)manipulation)such)a)decision)has)
almost)lost)its)potential)to)surprise)us.)(4-5)))
due+
______________________________________________________$and$genetic$manipulation$such$a$decision$$
has$almost$lost$its$potential$to$surprise$us.$
c. Couples)who)can’t)conceive)naturally)are)often)shocked)to)realise)that)doctors)cannot)just)wave)a)wand)
and)create)a)baby)for)them)...)(13-14)))
able)
______________________________________________________$are$often$shocked$to$realise$that$doctors$
cannot$just$wave$a$wand$and$create$a$baby$for$them.$
d. People)in)the)Western)world)are)beginning)to)believe)that)life)should)be)completely)controllable.)(20-21))
)
control)(noun))
People$[…]$are$beginning$to$believe$that$_______________________________________________________$
e. If)our)culture)didn’t)have)this)impatient)attitude)to)nature,)this)arrogant)belief)that)physical)and)even)
mental)illnesses)can)always)be)conquered,)where)would)we)be?)(25-26)))
unless)
____________________________________________________________$this$arrogant$belief$that$physical$$
and$even$mental$illnesses$can$always$be$conquered,$where$would$we$be?$
f. Certainly)we)in)the)West)can)dream)of)perfect)control)over)our)health)...)(29)))
used)to)
Certainly$we$in$the$West$$___________________________________________________________________$
3)
)
g. ...)deaths)from)alcoholKrelated)car)crashes)rose)sharply)last)year.)(47) )
rise+(noun))
_________________________________________________________$$alcoholUrelated$car$crashes$last$year.$
h. ...)our)[...])ability)to)control)our)lives.)(60)))
capable)
We$$____________________________________________________________________________________$
i.
Nor,)of)course,)does)the)dream)of)total)control)take)any)account)of)the)unspeakable)inequalities)in)the)
world.)(61-62)))
consideration)
Nor,$of$course,$does$the$dream$of$total$control$ _________________________________________________$
________________________________________________________________________________________$$
j.
...)although)scientists)might)one)day)be)able)to)save)us)even)from)our)genes,)they)still)won’t)be)able)to)save)
us)from)ourselves.)(67-68)))
in+spite+
____________________________________________________________$,$they$still$won’t$be$able$to$save$us$$
from$ourselves.$
Section)III:)Reading+comprehension.+(Total)credits:)24)))
1. Short+answer+questions.+Write)complete)short)sentences)(max.)2))to)answer)the)questions)in)your)own)
words.)You)are)awarded)credits)for)both)content)and)correctness)of)the)language.)+
24+credits+
a. What)is)the)decision)taken)by)the)House)of)Lords?)
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________))
b. What)is)seen)to)be)the)benefit)of)“designer)babies”?)
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________))
c. What)is)the)main)argument)given)by)the)House)of)Lords)for)its)decision?)
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________))
d. Sum)up)the)criticism)Natasha)Walter)makes)about)this)decision.)
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________))
e. Why)does)Natasha)Walter)think)that)“the)reality)of)our)lives)so)often)falls)so)far)short)of)the)dreams)of)both)
science)and)science)fiction”?)
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________))
f.
What)is)the)fundamental)criticism)mentioned)in)the)last)sentence?)
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________))
4)
)
Section)IV:)Writing.))
1. Information.+Take)a)moment)to)remember)important)rules)and)regulations)for)Part)IV.)
a.
b.
c.
d.
e.
f.
Choose)ONE)topic)and)make)sure)you)stick)to)the)topic.))
You)may)use)a)monolingual)dictionary.))
Do)not)use)abbreviations)(except)e.g./)i.e.).))
On)the)sheets)used)for)the)essay)please)leave)a)rightKhand)margin)of)about)1)inch.)
Put)page)numbers)and)your)name)on)every)sheet)you)write)on.)You)must)hand)in)all)the)sheets)you)
use.))
Indicate)the)number)of)words)at)the)end)of)the)text.))
2. Essay+topics.+Choose)ONE)of)the)topics)below)and)write)an)essay)of)350K400)words.)Set)your)own)title.))
1. Discuss)the)quotation)below.)
‘When you see something that is technically sweet, you go ahead
and do it and you argue about what to do about it only after you
have had your technical success. That is the way it was with the
atomic bomb.’
Julius Robert Oppenheimer, American physicist (1904-1967).
2. Science)and)politics)–)two)completely)different)matters?)Do)you)agree)or)do)you)think)there)is)‘good)
science’)and)‘bad)science’?)Give)your)arguments)using)examples.))
3. In)the)form)of)an)essay,)write)a)letter)to)the)editor)in)order)to)discuss)Natasha)Walter’s)arguments.)
Give)your)own)opinion.))
4. ‘Save)us)from)ourselves.’)—)Be)it)science,)God,)or)any)other)earthly)power:)why)should)we)be)saved)
from)ourselves?))
5. Discuss)the)quotation)below.)
‘O, brave new world that has such people in't!’
William Shakespeare, The Tempest (V.1. 184-187)
5)
)
Transcript++
BBC Schools GCSEBitesize – Science with the Naked Scientists
Transcript: Reproduction and Cloning:
Part One: Reproduction
CHRIS:
Hello and welcome to GCSEBitesize, with me, Chris Smith, and with Kat Arney –
we’re from the Naked Scientists.
Now new humans, animals and plants don’t just appear out of nowhere: they all
need to reproduce. And in this podcast we are going to find out how it all
happens. But first, Kat, why is it that – sadly for some – we tend to look like
our parents?
KATE:
Most people, animals and plants do look a lot like their parents because they
share their genes, and this is the genetic information that tells us what we
look like and makes us who we are.
CHRIS:
Ok, so tell us a bit more about genes: what exactly are they?
KATE:
Gene is just the name of the section of DNA that tells your cells to make one
particular protein; so one gene is the instruction for one protein. And in fact,
to make a whole organism, you need lots and lots and lots of different genes
with different functions. In fact, humans have around 30,000 genes, and they all
add up to make us unique.
CHRIS:
And where can we find these genes?
KATE:
Genes are encoded by our DNA, and that’s found packed up in the nucleus of cells
in the form of chromosomes. Each chromosome contains thousands of genes. For
example, our 30,000 genes are packed up in 23 matching pairs of chromosomes,
while tiny little fruit flies have four pairs of chromosomes that carry around
13,600 genes.
CHRIS:
That’s quite a lot. So if we share our parents’ genes, how does this actually
happen?
KATE:
Well, humans use sexual reproduction, which means that you need a man and a
woman to make a baby – as we all know. And many other animals and plants also
use this method, too. But some do manage to go solo and reproduce asexually,
without the need for a partner.
CHRIS:
Okay, so let’s look at the sexual reproduction first: how does that work?
KATE:
To start with, you need gametes, and these are specialised sex cells. So in
humans we have male sex cells, which are the sperm, and in females we have eggs
or ova, and contains half the number of chromosomes you need to make a new
6)
)
human, one of each of those 23 pairs. And these are referred to as being
haploid.
CHRIS:
So what happens when you actually make a baby?
KATE:
Well, when you make a baby the egg and sperm fuse together at the moment of
fertilization. And this is the mixing of those two haploid sets of chromosomes
to make a full, or diploid, set. And it also mixes together the characteristics
from your mum and from your dad, so you end up with a blend of the two that
makes you unique. So, you might get your dad’s nose shape or hair colour, but
you might get your mum’s eye colour.
CHRIS:
And what about the other sort that you mentioned, the asexual reproduction?
KATE:
Yes, there’s only need to one parent, and because there’s no mixing of the
genes, the offspring will be exactly the same as the parents, and we sometimes
refer to them as clones.
CHRIS:
Sounds a bit Sci-Fi.
KATE:
Well it does, but that’s just a scientific word that simply means animals or
plants that are genetically identical.
CHRIS:
So where do you see that kind of reproduction?
KATE:
A good place to start looking is the plant world. So, for example, potatoes lay
down tubers, and these are underground storage organs that grow into a new stock
of potatoes the following year. And daffodils lay down lateral buds in their
bulbs, which grow up the following spring.
CHRIS:
Anything else?
KATE:
Well, some plants can make little side branches with tiny plantlets on them. And
you can see this if you look at a busy lizzie or at a spider plant. And of
course, strawberries produce runners, which creep along the ground, bearing new
little plants.
CHRIS:
Are there any animals that behave in the same way?
KATE:
Well, it’s certainly less common in animals than plants, but some do, such as:
sea anemones and starfish.
CHRIS:
So we’ve looked at how animals and plants usually reproduce themselves. And in
Part Two, we’ll se how we can manipulate this, using technologies to produce
clones, as well as finding out what genetic modification actually means.
7)
)
Part Two: Cloning and Genetic Modification
CHRIS:
Hello and welcome to GCSEBitesize, with me, Chris Smith, and with Kat Arney – we’re
from the Naked Scientist.
CHRIS:
In Part One we found out how plants and animals reproduce. And now in Part Two we
are going to find out whether we can use this understanding for our own needs.
KATE:
Well, yes, we can, and we do. For example, we know how to make identical copies of
plants or clone them. And this has important implications for commercial farmers
and flower growers.
CHRIS:
How so?
KATE:
Well, this means that a good variety of plants, such as a beautiful flower or a
high-yielding crop, can be produced on a massive scale quickly and cheaply.
CHRIS:
So how does that work, though?
KATE:
The easiest way to do this is just to take a cutting, and you cut off a little
branch of the parent plant, strip off the lower leafs, stick in the pot of compost.
Now some people also use plant hormones on that stem to encourage new roots to
grow. And often they’ll cover the new plants in plastic, to keep it warm and moist.
And you can actually do this at home with a lot of garden plants.
CHRIS:
And what about more complicated ways that I’ve heard of for cloning plants?
KATE:
Another way is called tissue culture. So you scrape tiny pieces off the parent
plant and put them into sterile agar jelly with some plant hormones, and these tiny
pieces then grow into little plantlets, which can be potted out into compost,
though this is tricky and more expensive than taking cuttings.
CHRIS:
And what about animals, Kat, can they be cloned in the same way?
KATE:
We certainly can clone animals and being able to do this has big commercial
implications. For example, being able to clone a cow that makes lots of milk,
although this kind of technology is still at a relatively early stage, and it is
certainly much harder than cloning plants.
CHRIS:
So if we do want to do it, how do you clone an animal?
KATE:
Well, there’s two ways to do it. The first way is through embryo transplants.
So, you take an embryo at a very early stage, when it’s just a tiny ball of a few
cells, then separate those cells, grow them in the lab and then transplant them
back into a host mother. Now the offspring won’t be absolutely identical to their
mother, because they’ve still come from a fertilised embryo, but they will all be
identical to each other.
CHRIS:
But can we make clones that will be identical to the animal they came from?
)
KATE:
Yes, we can, and this is done by nuclear transfer: so you take an unfertilized egg
cell from the ovary of a female animal and then you take a cell from the animal you
want to clone, and using a tiny glass pipette, you carefully take the nucleus
containing all the DNA out of the cell and inject it into the egg. And then the egg
is activated, development starts, using the genetic instructions from that
transplanted nucleus, and the growing embryo’s just put back into the womb of the
foster mother and grows into a baby.
CHRIS:
And has anyone actually done this?
KATE:
Well, this has first been achieved by Professor Ian Wilmut and his team, and they
made Dolly the sheep in 1996. She was made using an unfertilized sheep’s egg, fused
with the nucleus from another sheep’s udder cell. Dolly made headline news when she
was born. And although she died in 2003, other animals have been cloned using this
technique, including a cat and a horse.
CHRIS:
And as well as cloning we here a lot in the news about genetic modification. What’s
that? Is that different?
KATE:
Yes it is different. Genetic modification, or GM, is also known as genetic
engineering, and it simply allows scientists to swap genes from the DNA of one
organism and stick it into the DNA of another.
CHRIS:
And how do we do that?
KATE:
This technique relies on special enzymes, which you use to cut out the gene from
the DNA of one organism, cut a gap in the DNA of another organism and stick the two
together. So, this basically means that you’ve added a gene form one organism, such
as, say, an insect, into the DNA of another, such as a plant, and this new gene
will provide a new function for that modified organism, such as making a useful
substance, or making it grow better. And as the modified organ grows and
reproduces, it will also send that new gene down the generations.
CHRIS:
Are there any good examples of how we use this technology?
KATE:
An important area is medicine. For example, we can now make genetically modified
bacteria that produce essential human proteins. So people with diabetes, who need
to inject themselves with insulin – that’s a hormone made by the pancreas – and
this used to be made from cow or pig pancreases, so this could sometimes create
allergic reactions in people.
Then scientists managed to take the human gene that carries the instructions to
make insulin and put it into bacteria. These genetically modified bacteria then
multiply many, many times and making [sic!] lots of human insulin, and this can be
purified and given to people with diabetes safely. So in this case, GM technology
has made a really difference to a lot of people.
CHRIS:
So GM is definitely not the same as cloning?
KATE:
No the two are very different and you shouldn’t confuse them. So, with cloning you
are producing an exact copy of an animal or plant, with an identical set of all its
genes. With genetic modification you’re just copying or multiplying specific genes.
)
Although, rather confusingly, sometimes people talk about this using the term gene
cloning.
And with GM technology you can swap genes between species, so, for example, between
insects and plants or between different types of animals. But with cloning you’re
only making copies of the same species.
CHRIS:
This all sounds pretty clever, Kat, so what are the potential benefits of using GM
and cloning techniques like this?
KATE:
Well, there’s absolutely loads we can do. For example, scientists are working on a
sheep that can produce human proteins treating people with cystic fibrosis, and
this is a serious disease that affects the lungs. And they’ve even made tobacco
plants that glow in the dark when they need watering – Oh, the possibilities are
endless!
CHRIS:
But are there any drawbacks to this kind of thing?
KATE:
Well, some people do worry that GM techniques are unethical and should either be
banned or used very carefully. For example, there are genetically modified crops
that are resistant to weed killers. But some people argue that this actually means
more weed killers are used, which could harm the environment, rather than actually
find better ways to farm. And there are also worries that, for example, modified
plants might breed with wild plants, spreading these modified genes through wild
populations. And also, finally, as cloning techniques improve, there are really
ethical debates about rights and wrongs of human cloning – if it does ever turn to
be possible.
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