14
Free
Forum
Science
and
Technology
April
2O0J
TECHNICALLY
OrPQf
&'
$rv
To
upgrade
or
not
to
upgrade
Liana
Ziemer
To
upgrade
or
not
to
upgrade;
that
is
the
question.
We
get
inundated
with
advertising
that
boasts
the
virtues
of
cutting
edge
software
and
hardware.
The
computer
gods
would
have
us
believe
that
we
need
to
keep
up
with
the
latest
improvements
or
we'll
be
left
behind
with
a
non-functioning
system.
Before
blindly
accepting
this
notion
there
are
a
number
of
factors
that
need
to
be
considered
in
regards
to
upgrading
your
computer
system.
First,
consider
your
needs
(as
opposed
to
Bill
Gates
need
for
more
money).
If
you
use
your
machine
primarily
for
email
and
word
processing,
your
demands
on
it
will
be
minimal.
You
do
not
need
to
bow
to
the
gods
and
get
a
$3000
loan
for
a'machine
that
will
blow
your
hair
back.
Sometimes
just
adding
more
RAM
(memory)
will
make
a
world
of
difference.
Upgrading
the
CPU
(brain
power)
is
the
logical
option.
If
you
do
opt
to
upgrade
the
CPU,
have
your
neighbourhood
guru
check
to
make
sure
everything
will
be
compatible.
Do
not
be
tempted
to
run
the
latest
operating
system
on
an
older
machine,
as
they
lack
the
gumption
to
run
these
resource
hungry
programs.
Upgrading,
in
this
case,
will
actually
downgrade
your
production.
If
you
are
considering
purchasing
the
newest
version
of
an
operating
system,
check
out
the
price
of
a
basic
tower
with
the
system
pre-installed.
Often
the
cost
is
not
much
more
and
you'll
get
the
new
components
as
well.
Your
bank
account
is
sitting
somewhere
around
zero,
so
what
happens
if
you
don't
upgrade?
It
may
mean
your
system
is
inadequate
to
run
some
newer
programs,
especially
if
they
are
multimedia
applications
with
a
lot
of
video
and
sound.
If
graphic
intensive
games
are
your
primary
use
for
a
computer
that
is
not
keeping
up,
you
may
have
to
admit
defeat
and
toss
the
system
and
start
with
a
new
one.
No
matter
what
you
use
your
computer
for
the
same
as
everything
from
cars,
to
appliances
to
some
relationships.-
eyefitu-,
''ally
it's
time
to
ditch,
dump,
delete,
and
start
over.
V7TiT7T3
With
H&R
Block's
$49.95
flat
rate
for
students,
tax
returns
have
never
been
simpler.
Call
1-800-HRBLOCK
or
visit
hrblock.ca.
H
H&R
BLOCK
just
plain
smart"
f
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JOiU
Science
Sidebar
1
It's
a
boy!
It's
a
girl!
Fiona
Grisswell
It's
a
boyIt's
a
girl.
After
hearing
thell
baby
is
healthy,
these
are
the
"words
new
parents
anticipate
the
most.
We're
all
c
familiar
with
the
basic
mechanisms
of
sex
determination
from
our
high
school
biology
class,
but
exactly
how
does
this
process
happen?
r
It's
a
well-known
fact
that
each
person
calm
two
sex
chromosomes;
The
woman
carries
twoi
chromosomes
(xx)
while
the
man
carries
an
x
i
y
chromosome
(xy).
It
is
the
man's
sperm
i
determines
the
sex
of
the
child,
depending
onwl
chromosome
it
contributes
during
fertilization
the
sperm
donates
an
x
then
the
child
will
be
a;
and
if
it
donates
a
y
then
a
baby
boy
will
be
This
is
not
a
conscious
choice
on
the
part
of
prospective
parents.
-
Ihe
y
chromosome
is
ditrerent
in
shape
much
smaller
than
the
x
chromosome.
It
is
beliei
that
the
y
chromosome
chain
of
DNA
(this
is
blueprint
for
eenetic
inheritance)
carries
much
genetic
information
than
the
x
chromosome,
f
Most
genes
are
present
in
pairs,
but
in
the
mi
sex
chromosome
each
gene
usually
occurs
01
once.
One
of
these
genes
carried
by
the
y
chroi
some
serves
in
the
development
of
the
male
gon:
and
is
therefore
important
in
determining
whei
the
baby
will
be
male
rather
than
female.
j
Now
we
begin
to
understand
what
influene
the
sex
of
a
child
but
we
still
don't
have
a
clef.
understanding
of
the
determining
factors.
Isthei
bioloeical
factor
that
controls
how
the
v
chroi
ftr-a"5--
-
ft
t
.
SUIJ1C
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VJl
IS
UlC
ijicsciicc
Ul
UIC.
chromosome
enough?
j
Up
until
the
7th
week
of
gestation
there
are
Visible
sexual
differences
in
the
embryo.
This
known
as
the
"sexually
indifferent
stage."
Thegi
on
the
y
chromosome
which
serves
in
the
devel
ment
of
male
gonads
is
called
SRY.
In
week!
structure,
called
the
bipotential
gonad,
begins
take
on
the
appearance
of
either
a
testis
or
an
ovi
At
about
the
same
time,
hormones
produced
the
testis
or
ovary
start
the
development
of
into
and
external
sexual
structures.
Testosterone,
wh
is
produced
by
the
testes,
is
responsible
for
embryo
developing
male
characteristics.
The
pi
ence
of
the
SRY
gene
on
the
chromosome
"tu
on"
this
production.
f
If
the
SRY
gene
is
the
gene
responsible
determining
male
sex,
then
how
do
we
expl
apparent
exceptions
to
the
rule?
j
It
turns
out
that
the
majority
of
males
with
chromosomes
carry
the
end
of
the
y
chromosi
This
is
the
portion
carrying
the
gene
that
di
mines
testis
development.
This
segment
of
chromosome
is
found
on
the
x
chromosome
was
donated
by
the
father.
In
females
carrying!
chromosomes,
approximately
10
have
delel
of
the
same
potion
of
the
y
chromosome
thai
males
carrv.
How
does
this
haoDen?
'
'
3
In
normal
meiosis,
the
x
and
y
chromosoi
pair
anu
recomoine
in
a
nmiieu
region,
in
si.
cases
the
chromosomes
pair
and
recombine
more
proximal
fashion.
The
end
result
is
thatt
sky
gene
is
transierrea
to
tne
x
cnromosome
ai
deleted
from
the
v
chromosome.
J
i
Knowing
how
sex
is
determined
opens
upj
field
of
sex
preselection.
In
many
areas
ofP
world,
one
sex
is
preferred
over
the
other
forp(
ous
economic
and
social
reasons.
This
is
an
f
that
is
sure
to
escalate
in
the
future
as
the
ethst
and
moral
implications
of
such
choices
are
debiri
For
those
of
you
reading
this
column,
such
a
cr
will
probably
never
be
a
consideration
as
youfj,
your
family.
But
then
again,
you
never
know.
I
I