01 overview topic1 - pearson schools and fe colleges | … · 2015-03-19 · daphnia). use this...
TRANSCRIPT
Salters-Nuffield Advanced Biology Resources
© University of York, developed by University of York Science Education Group. Page 1 of 4 This sheet may have been altered from the original.
Topic 1 Lifestyle, Health and Risk Resources Overview
Des
crip
tio
n
An
inte
ract
ive
pres
ent
atio
n to
giv
e yo
u a
n ov
ervi
ew
of th
e to
pic.
An
inte
ract
ive
revi
ew o
f the
GC
SE
kno
wle
dg
e yo
u ne
ed
for
this
topi
c.
An
inte
ract
ive
test
of h
ow w
ell y
ou k
now
the
mat
eria
l in
the
GC
SE
rev
iew
.
Pro
vid
es a
det
aile
d ac
coun
t of
Mar
k’s
and
Pet
er’s
ex
peri
ence
s w
ith c
ardi
ovas
cula
r di
seas
e.
A p
ract
ical
de
mon
stra
tion
of d
iffus
ion
and
mas
s flo
w
that
allo
ws
con
side
ratio
n of
why
ani
mal
s ha
ve a
ci
rcul
atio
n sy
stem
.
Lets
you
rel
ate
the
solv
ent p
rope
rtie
s of
wat
er to
so
me
of th
e fu
nctio
ns o
f wat
er.
Exa
min
e th
e st
ruct
ure
of a
ma
mm
alia
n he
art b
y co
mpl
etin
g th
e di
ssec
tion
in th
is a
ctiv
ity.
Look
in d
eta
il a
t th
e st
ruct
ure
of a
mam
mal
ian
hear
t us
ing
a si
mul
ated
dis
sect
ion.
Lets
you
rel
ate
the
solv
ent p
rope
rtie
s of
wat
er to
so
me
of th
e fu
nctio
ns o
f wat
er.
Inve
stig
ate
how
the
stru
ctur
e o
f blo
od v
esse
ls
rela
tes
to th
eir
func
tion
in th
is p
ract
ical
act
ivity
.
Lets
you
com
ple
te W
illia
m H
arve
y’s
exp
erim
ent
that
de
mo
nstr
ated
one
-way
val
ves.
The
sim
ulat
ion
with
this
act
ivity
sho
ws
you
the
card
iac
cycl
e as
a c
ontin
uous
pro
cess
.
Lets
you
sum
mar
ise
the
step
s in
the
deve
lop
men
t of
athe
rosc
lero
sis
and
clot
form
atio
n.
Tec
hn
icia
n
Sh
eet
No
No
No
No
Yes
Yes
Yes
No
Yes
Yes
No
Yes
Yes
Tea
cher
S
hee
t
No
No
No
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Stu
den
t S
hee
t
No
No
No
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Inte
ract
ive
com
po
nen
t
Yes
(p
rese
ntat
ion)
Yes
(rev
iew
)
Yes
(tes
t)
No
No
Yes
(tut
oria
l)
No
Yes
(tut
oria
l)
Yes
(tut
oria
l)
No
No
Yes
(tut
oria
l)
No
Tit
le
Mar
k's
and
Pet
er's
st
orie
s
Dem
ons
trat
ing
mas
s flo
w
An
ide
al tr
ansp
ort
med
ium
Str
uctu
re o
f the
hea
rt
(dis
sect
ion)
Str
uctu
re o
f the
hea
rt
(sim
ulat
ed
diss
ectio
n)
An
ide
al tr
ansp
ort
med
ium
Inve
stig
atin
g ar
terie
s an
d ve
ins
Har
vey’
s ci
rcul
atio
n ex
peri
men
ts
The
car
diac
cyc
le
Ath
eros
cler
osis
Res
ou
rce
typ
e
Top
ic in
tro
duct
ion
GC
SE
rev
iew
GC
SE
rev
iew
test
Act
ivity
1.1
Act
ivity
1.2
Act
ivity
1.3
Act
ivity
1.4
Act
ivity
1.5
Act
ivity
1.3
Act
ivity
1.6
Act
ivity
1.7
Act
ivity
1.8
Act
ivity
1.9
SAMPLE MATERIA
L
Salters-Nuffield Advanced Biology Resources
© University of York, developed by University of York Science Education Group. Page 2 of 4 This sheet may have been altered from the original.
Topic 1 Lifestyle, Health and Risk Resources Overview
Des
crip
tio
n
Lets
you
co
nsid
er h
ow
nar
row
ing
of th
e ar
terie
s af
fect
s bl
ood
flow
.
Thi
nk a
bou
t pe
rcep
tion
of r
isk
and
estim
ate
risk
s fo
r a
rang
e of
dis
eas
es in
this
act
ivity
.
Inve
stig
ate
corr
elat
ion
and
caus
e us
ing
dat
a on
In
tern
et a
cces
s.
Eva
luat
e th
e d
esig
n of
stu
die
s us
ed to
iden
tify
heal
th r
isk
fact
ors.
Lets
you
fin
d o
ut if
car
diov
ascu
lar
dis
ease
ris
k ch
ange
s w
ith a
ge.
You
use
a s
phyg
mom
ano
met
er, a
blo
od-
pre
ssur
e m
onito
r or
the
acco
mp
anyi
ng s
imul
atio
n to
mea
sure
bl
ood
pre
ssur
e.
Brin
g to
get
her
all t
he id
eas
ab
out b
lood
pre
ssur
e us
ing
the
conc
ept m
ap in
this
act
ivity
.
The
inte
ract
ive
tuto
rial i
n th
is a
ctiv
ity w
ill h
elp
you
und
erst
and
carb
ohyd
rate
str
uct
ure.
You
can
imm
obi
lise
lact
ase
and
use
it to
hyd
roly
se
lact
ose.
Com
plet
e th
is in
tera
ctiv
e tu
toria
l to
help
you
un
der
stan
d lip
id s
truc
ture
.
Use
the
diet
ary
anal
ysis
sof
twar
e in
this
act
ivity
to
wor
k ou
t you
r en
ergy
bu
dget
and
det
erm
ine
whe
ther
yo
u ar
e g
ettin
g th
e rig
ht a
mo
unt
of e
nerg
y.
Wor
k ou
t Bod
y M
ass
Inde
x an
d w
aist
-to-
hip
m
easu
rem
ents
.
Tec
hn
icia
n
Sh
eet
No
No
No
No
No
Yes
No
No
Yes
No
No
No
Tea
cher
S
hee
t
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Stu
den
t S
hee
t
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Inte
ract
ive
com
po
nen
t
No
No
Yes
(spr
eads
heet
)
No
No
Yes
(tut
oria
l)
No
Yes
(tut
oria
l)
No
Yes
(tut
oria
l)
Yes
(tut
oria
l)
No
Tit
le
Blo
od
flow
Est
imat
ing
risk
Cor
rela
tion
and
caus
atio
n
Iden
tifyi
ng
heal
th r
isks
Ana
lysi
s of
ca
rdio
vasc
ular
dis
ease
da
ta
Mea
surin
g b
lood
pr
essu
re
Blo
od
pres
sure
su
mm
ary
Car
boh
ydra
te s
truc
ture
Bio
tech
nolo
gy t
o th
e re
scue
Lipi
ds
You
r en
ergy
bud
get
Obe
sity
indi
cato
rs
Res
ou
rce
typ
e
Act
ivity
1.1
0
Act
ivity
1.1
1
Act
ivity
1.1
2
Act
ivity
1.1
3
Act
ivity
1.1
4
Act
ivity
1.1
5
Act
ivity
1.1
6
Act
ivity
1.1
7
Act
ivity
1.1
8
Act
ivity
1.1
9
Act
ivity
1.2
0
Act
ivity
1.2
1
SAMPLE MATERIA
L
Salters-Nuffield Advanced Biology Resources
© University of York, developed by University of York Science Education Group. Page 3 of 4 This sheet may have been altered from the original.
Topic 1 Lifestyle, Health and Risk Resources Overview
Des
crip
tio
n
Con
side
rs th
e ev
iden
ce fo
r a
caus
al r
elat
ion
ship
be
twe
en b
loo
d ch
oles
tero
l lev
els
and
CV
D.
Con
side
rs th
e in
heri
tanc
e of
pre
disp
ositi
on to
ca
rdio
vasc
ular
dis
ease
incl
udin
g a
case
stu
dy.
Con
side
rs th
e ro
le o
f ant
ioxi
dant
s in
you
r di
et a
nd
lets
you
det
erm
ine
if yo
ur d
iet
cont
ains
eno
ugh
an
tioxi
dant
vita
min
s.
Inve
stig
ate
the
vita
min
C c
ont
ent o
f a r
ang
e of
frui
t ju
ices
.
Thi
s te
ache
r-le
d de
mo
nstr
atio
n le
ts y
ou ta
ke p
art i
n an
inve
stig
atio
n of
som
e fa
ctor
s th
at a
ffect
blo
od
pres
sure
an
d h
eart
rat
e.
You
des
ign
an e
xper
imen
t to
find
out
whe
the
r ca
ffein
e af
fect
s th
e he
art r
ate
of w
ater
flea
s (D
aphn
ia).
Use
this
he
alth
y he
art q
uiz
to t
est y
our
know
ledg
e of
th
e he
art a
nd C
VD
ris
k fa
ctor
s.
Con
side
rs s
ome
of th
e w
ays
that
peo
ple
use
sc
ient
ific
know
ledg
e to
red
uce
thei
r ris
k of
CH
D.
Use
this
act
ivity
to c
heck
you
r no
tes
for
revi
sion
.
Inte
ract
ive
end
-of-
topi
c te
st.
Exa
m s
tyle
writ
ten
end-
of-t
opic
test
Tec
hn
icia
n
Sh
eet
No
No
No
Yes
Yes
Yes
No
No
No
No
No
Tea
cher
S
hee
t
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No
No
Yes
Stu
den
t S
hee
t
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No
Yes
Inte
ract
ive
com
po
nen
t
No
No
No
No
Yes
No
No
No
No
Yes
(tes
t)
No
Tit
le
Cho
lest
ero
l an
d C
VD
Sud
den
dea
th in
at
hlet
es
Are
you
get
ting
eno
ugh
an
tioxi
dant
s?
Is h
igh
C a
ll it
clai
ms
to
be?
Red
ucin
g st
ress
Doe
s ca
ffein
e af
fect
he
art r
ate?
Hea
lthy
hear
t qui
z
Mak
ing
deci
sio
ns
Che
ck y
our
not
es
Res
ou
rce
typ
e
Act
ivity
1.2
2
Act
ivity
1.2
3
Act
ivity
1.2
4
Act
ivity
1.2
5
CO
RE
Act
ivity
1.2
6
Act
ivity
1.2
7
CO
RE
Act
ivity
1.2
8
Act
ivity
1.2
9
Act
ivity
1.3
0
Top
ic te
st
Top
ic te
st
SAMPLE MATERIA
L
Salters-Nuffield Advanced Biology Resources
© Pearson Education Ltd 2015. This sheet may have been altered from the original. Page 4 of 4
Topic 1 Lifestyle, Health and Risk Resources Overview
Des
crip
tio
n
Lear
n ab
out c
ard
iopu
lmon
ary
resu
scita
tion
in th
is
exte
nsio
n.
In th
is e
xten
sio
n re
ad a
bout
var
ious
test
s us
ed to
di
agn
ose
card
iova
scu
lar
dise
ase.
Fin
d ou
t mor
e ab
out
func
tion
al fo
ods
in th
is
exte
nsio
n.
You
can
re
ad m
ore
abou
t ne
w tr
eatm
ents
for
card
iova
scu
lar
dise
ase
in th
is e
xten
sion
.
Tec
hn
icia
n
Sh
eet
No
No
No
No
Tea
cher
S
hee
t
Yes
No
Yes
No
Stu
den
t S
hee
t
Yes
Yes
Yes
Yes
Inte
ract
ive
com
po
nen
t
No
No
No
No
Tit
le
Som
eone
sav
ed
my
life
toda
y
Tec
hniq
ues
used
in
med
ical
an
alys
is
Fun
ctio
nal
foo
ds a
nd
CH
D
New
trea
tme
nts
for
card
iova
scul
ar d
isea
se
Res
ou
rce
typ
e
Ext
ensi
on
1.1
Ext
ensi
on
1.2
Ext
ensi
on
1.3
Ext
ensi
on
1.4
SAMPLE MATERIA
L
Salters-Nuffield Advanced Biology Resources
© University of York, developed by University of York Science Education Group. Page 1 of 2 This sheet may have been altered from the original.
Topic 1 Lifestyle, Health and Risk Forward Planning
Some of the following items may need ordering in advance for activities in this topic.
Safety notes are in the sheets for each activity.
Centres will need to select the activities they wish to complete, bearing in mind the time available.
Activity Item(s) Quantity per student or group of students
Notes
A1.4 Mammalian heart
Virkon (MicroSol is also suitable)
1 See note for A1.6
For disinfection at 1%
Available in pet shops or through chemical suppliers.
A1.6 Rings cut from sections of arteries and veins
1 of each If plucks (hearts and lungs) are obtained from a butcher for A1.4 the rings can be cut from the vena cava and aorta and frozen for this practical.
Asking the butcher to remove the liver should make plucks much cheaper.
Virkon For disinfection at 1%. Available in pet shops or through chemical suppliers.
Microscope
Eye piece graticule
Stage micrometer
Prepared slides of tissue showing capillaries; also slide of vein and artery TS
With a 40 lens
Students can share the slides between 3 or 4.
A1.15 Sphygmomanometer and stethoscope, or a blood pressure monitor
The interactive tutorial is available from SNAB Online if these are not available.
A1.18 Lactase
Sodium alginate solution (2%)
10 cm3 syringe barrel
Semi-quantitative glucose test strip
Calcium chloride solution (1.5%)
2 cm3
8 cm3
1
1
Approximately 20 cm3
See safety information in the Technician Notes.
They will need more if they look at effect of rate of flow.
Benedict’s test can be completed as an alternative.
See safety information in the Technician Notes.
A1.25
CORE
DCPIP (1%)
Vitamin C solution (1%)
10 cm3 syringe or burette
1 cm3
A1.26 Relaxation tape or video There is a relaxation interactive tutorial accessible from SNAB Online.
SAMPLE MATERIA
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Salters-Nuffield Advanced Biology Resources
© University of York, developed by University of York Science Education Group. Page 2 of 2 This sheet may have been altered from the original.
Topic 1 Lifestyle, Health and Risk Forward Planning
A1.27
CORE
Daphnia
Caffeine solution (0.5% w/vol)
Cavity slides
9 per student + extras
3 per student
Approximately 5 cm3
SAMPLE MATERIA
L
Salters-Nuffield Advanced Biology Resources
© University of York, developed by University of York Science Education Group. Page 1 of 1 This sheet may have been altered from the original.
Activity 1.2 Student Sheet
DEMONSTRATING MASS FLOW
Purpose To calculate rate of diffusion.
To appreciate speed of diffusion in air.
To observe mass flow.
SAFETY
Wear eye protection, lab coats and disposable gloves.
The experiment must be undertaken in a fume cupboard.
YOU NEED
● Dilute ammonium hydroxide
● Two glass tubes
● Bungs to fit glass tubes
● 16 small pieces of litmus paper
● Glass or wooden rod
● Two small pieces of cotton wool
● Forceps
● Dropping pipette
● Stopclock
● Clamp stand, boss and clamp or piece of adhesive tack
● Ruler
Procedure 1 Your teacher/lecturer will set up a glass tube
with litmus paper as shown in Figure 1 and measure the distance between the pieces of litmus paper.
2 In a fume cupboard add a few drops (about six) of ammonium hydroxide solution to a small ball of cotton wool and then place it at one end of the glass tube. Seal both ends of the tube with rubber bungs. Immediately start a stopclock. Ammonia is given off by the solution and diffuses along the tube. The litmus paper changes colour from red to blue in the presence of ammonia gas.
3 Record how long it takes each piece of litmus paper to change colour.
Figure 1 Glass tube with litmus paper.
4 Using a second tube without rubber bungs, place the cotton wool with ammonium hydroxide at one end.
5 Using a large syringe, blow air gently through the tube. Observe how quickly the litmus paper changes colour when the syringe is used.
Questions Q1 Explain how the ammonia moves along the tube with sealed ends.
Q2 Calculate the speed of diffusion along the tube and comment on your findings.
Q3 Explain how each of these factors would affect the rate of diffusion: a higher concentration of ammonium hydroxide b higher temperature c larger molecules replacing ammonium hydroxide.
Q4 Explain what is happening in the tube without bungs and how the model is similar to mass flow in a transport system, such as the mammalian circulatory system.
rubber bung
litmus paper (red)
clamp stand
SAMPLE MATERIA
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To be safe
ty rev
iewed
Salters-Nuffield Advanced Biology Resources
© University of York, developed by University of York Science Education Group. Page 1 of 1 This sheet may have been altered from the original.
Activity 1.2 Teacher Sheet
DEMONSTRATING MASS FLOW
Purpose
To calculate rate of diffusion.
To appreciate speed of diffusion in air.
To observe mass flow.
SAFETY
Wear eye protection, lab coats and disposable gloves.
The experiment must be undertaken in a fume cupboard.
Notes on the procedure It is presumed that most students will have observed diffusion in practicals at KS3 or KS4. However, it is worth students completing this practical or having it demonstrated to them to highlight the difference between diffusion and mass flow.
If students take an active part in this practical they need to know, in advance, how to use a fume cupboard.
The sealed tube allows measurements to be taken to determine the speed of diffusion. The open-ended tube demonstrates mass flow of ammonium hydroxide. It is virtually impossible to measure how quickly the litmus paper changes colour.
Stapling pieces of litmus paper to wooden splints and then sliding the splint into the tube overcomes the difficulty of getting the pieces along the tube.
If teaching topics in parallel (or when teaching Topic 2), the ideas here could relate to Fick’s law (Topic 2 2.1), which states that:
Rate of diffusion surfaceofthickness
ratio volume toarea Surface difference ionConcentrat
Answers Q1 Molecules are continuously moving due to their kinetic energy. There are more ammonia
molecules at the cotton wool end of the tube (high concentration) compared with the other end (a region of low concentration). There is a net movement of molecules due to their random movement from the region of their high concentration to the region of their low concentration.
Q2 The speed of diffusion at the end of the tube away from the cotton wool is slower than at the beginning. Rate of diffusion is dependent on the concentration gradient. Near the cotton wool there is a high concentration compared with the rest of the tube: this gives a steep diffusion gradient. Large numbers of ammonia molecules will be diffusing away from the cotton wool so the net movement is rapid. As the molecules diffuse away, their concentration decreases and further along the tube the diffusion gradient is less steep. As a result, the time taken for enough molecules to diffuse between the final two pieces of litmus paper and turn the last one blue will be much longer.
Q3 a Higher concentration will speed up diffusion because there is a steeper gradient.
b Higher temperature will speed up diffusion because the molecules will have more kinetic energy.
c Larger molecules would diffuse more slowly because in a vapour or gas, at a given temperature, the larger the molecule, the more slowly it moves.
Q4 The air in the tube moves along the tube and carries the ammonia with it. Blood works in the same way. The fluid is pumped around the body and carries within it substances to be transported.
SAMPLE MATERIA
L
To be safe
ty rev
iewed
Salters-Nuffield Advanced Biology Resources
© University of York, developed by University of York Science Education Group. Page 1 of 1 This sheet may have been altered from the original.
Activity 1.2 Technician Sheet
DEMONSTRATING MASS FLOW
Purpose
To calculate rate of diffusion.
To appreciate speed of diffusion in air.
To observe mass flow.
SAFETY
Wear eye protection, lab coats and disposable gloves.
The experiment must be undertaken in a fume cupboard.
Small amounts of 0.5 M ammonia solution can be used in a well-ventilated laboratory. When making up such solutions a fume cupboard, gloves and eye protection will be needed.
All ammonia solutions are best dispensed in a fume cupboard as the vapour, ammonia gas, is toxic and extremely irritating to the eyes and lungs.
Requirements per student or group of students
Notes
Eye protection, lab coats, disposable gloves and access to a fume cupboard
Two glass tubes Approximately 50 cm long and 2 cm in diameter.
Two bungs to fit glass tubes
Eight small pieces of red litmus paper Each piece approximately 1 cm in length. For ease of positioning in the tube the pieces of litmus paper can be stapled at intervals along a wooden splint.
Glass or wooden rod To position the litmus paper in the glass tube.
Two pieces of cotton wool Approximately 1.5 1.5 cm.
Forceps
Dilute ammonium hydroxide Any concentration around 0.5 M should work well.
Large syringe Any size is fine as long as it provides a good draught of air when the plunger is pushed in.
Dropping pipette
Stopwatch/clock
Two bosses, clamps and stands or pieces of adhesive tack
Instead of using a boss and clamp, rest the tubes on the bench with a piece of adhesive tack acting as a wedge to stop them rolling off.
Ruler
Notes
Figure 1 Glass tube with litmus paper (red).
cotton wool with ammonium hydroxide
litmus paper (red)
clamp stand
SAMPLE MATERIA
L
To be safe
ty rev
iewed
Salters-Nuffield Advanced Biology Resources
© University of York, developed by University of York Science Education Group. Page 1 of 2 This sheet may have been altered from the original.
Activity 1.27 Student Sheet Core Practical
DOES CAFFEINE AFFECT HEART RATE?
Purpose
To investigate the effect of caffeine on the heart rate of Daphnia (water fleas).
Caffeine Plants produce caffeine as an insecticide. Cocoa in South America, coffee in Africa and tea in Asia have all been used for hundreds of years to produce ‘pick me up’ drinks containing caffeine. These days, caffeine is also used as a flavour enhancer in a wide range of soft drinks. In addition, it has medicinal uses in painkiller preparations and is found in weight-loss drugs and as a stimulant in students’ exam-time favourites like PRO PLUS and Red Bull.
In humans, caffeine acts as a stimulant drug, causing increased amounts of stimulatory neurotransmitters to be released. At high levels of consumption caffeine has been linked to restlessness, insomnia and anxiety, causing raised stress and blood pressure. This can lead to heart and circulation problems.
The effect of caffeine on heart rate can be investigated using Daphnia (water fleas). The beating heart of a water flea can be seen through its translucent body, by placing the flea in a few drops of water in a cavity slide under the microscope.
Investigating the effect of caffeine on heart rate
SAFETY
If a stroboscope is used to show the Daphnia’s heart rate and you know you suffer from photosensitive epilepsy, tell your teacher and take appropriate precautions.
1 Scientific questions and information research State what you are going to investigate – try to express this as a hypothesis to test. What do you
think will be the effect of caffeine on the heart rate of water fleas? Write down your ideas and a prediction, and present relevant biological knowledge to support your suggestions.
Research relevant information – to help you decide on what you are going to investigate and how you will carry out the practical work, you might need to research the background science and methods people have used to investigate similar problems. When you write up your plan remember to give full details of any information sources you use and comment on their reliability.
2 Planning and experimental design Design an experiment that you can use to test your hypothesis – the developing practical skills
support in the resources will help you plan your investigation. Note: Daphnia are poikilothermic (cold blooded). Turn off the microscope lamp when not viewing the fleas.
The following equipment will be available:
Culture of Daphnia (water fleas)
Cavity slides
Dropping pipettes
Distilled water
Caffeine tablets
Cotton wool
Standard glassware (beakers, measuring cylinders, etc.)
Stopclock
Paper towels or filter paper
Microscope.
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Activity 1.27 Student Sheet Core Practical
Make sure your plan:
includes the hypothesis that you are testing
identifies the independent and dependent variables
identifies any other variables which may affect the outcome of the experiment and, where possible, controls or allows for them
includes a procedure which uses suitable apparatus that will give you measurements that will validly test your hypothesis, and explains why the apparatus is suitable and how the results will let you test the hypothesis
has a control, if appropriate, and this control is fully explained
includes replicates, and an explanation of why this is necessary
says what measurements you will make, how they will be made and the level of precision that you can expect in your measurements
identifies any potential sources of error (systematic or random) and how errors can be minimised
comments on any ethical issues that arise from using invertebrates in the experiment and explains how these will be taken into account in the practical method used
includes a risk assessment that identifies any risks and explains any safety precautions that need to be taken so as to reduce those risks.
3 Carrying out practical work safely and ethically
Either use the plan you have created after it has been checked by your teacher/lecturer or use a method supplied by your teacher/lecturer. If unexpected ethical or safety issues arise, deal with them sensibly, taking advice where needed and make a note of them. Record all measurements, including repeated ones, as soon as they are taken; with appropriate precision (i.e. a suitable number of significant figures) and units. Note any possible errors.
4 Analysis and interpretation of data
Present your data in an appropriate table and graph. For information on the features of a good table and graph see the Maths and Stats Support in the resources. If you have lots of repeated results, remember that you should work out mean values and present these in your report. This also lets you comment on the significance of your results. If the results that are used to calculate the means are very variable, any differences between the treatment means may not be significant. The range of values can be shown on the graph using bars on each point as a measure of the variation of the data. See Maths and Stats Support Sheet 10 – standard deviation – for details of how to work out standard error. NB: you need to make it clear what any bars on a graph are showing.
5 Conclusion and evaluation
In the discussion of your results you should use evidence from your data to identify any trends and patterns. You should quote some data that show the trend. You should then use biological knowledge to explain any patterns or trends identified. You should state a clear conclusion, summarising what you found out and comment on the validity of your conclusion. You should evaluate your experimental apparatus and methods, commenting on the accuracy and precision of your results.
Remember that the hypothesis you suggested may not be correct. In this case, the results will not show the patterns or trends that you expected. There may be a different trend or no trend at all. This is perfectly OK. You may be able to suggest an alternative explanation for your results. You may still think your hypothesis is sound, but that there are concerns about the experimental method used and that the results obtained are not very valid, i.e. they may not be testing the hypothesis appropriately. In this case, you cannot draw valid conclusions from the results and this should be explained in any write up. An experiment that does not produce the expected results is often as valuable to other researchers as a report that supports the original hypothesis. It allows other researchers to make informed decisions about the methods they will use in the future and it may allow them to suggest alternative ideas.
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Activity 1.27 Teacher Sheet Core Practical
DOES CAFFEINE AFFECT HEART RATE?
Purpose To investigate the effect of caffeine on the heart rate of Daphnia (water fleas).
SAFETY
Any student known to suffer from photosensitive epilepsy should be identified and appropriate precautions taken (sit out the experiment) before a stroboscopic light is used. Flickering lights in the range 5–30 Hz are thought to trigger seizures in sensitive individuals.
Notes on the procedure The Student Sheet that accompanies this activity guides students through planning and writing up this investigation. The Developing Practical Skills framework can be used in conjunction with this sheet: this can be found in the Skills Support section of SNAB Online. After students plan the investigation their plans can then be discussed with the group to highlight any omissions.
To support less able students, or to help with the organisation of practical work for a large group, students could be given the practical procedure at the end of these notes (see page 4). It provides a basic outline and will need to be read by students before starting the practical with decisions and modifications made as appropriate. The procedure is for a simple experiment; more able students could complete a more complex experiment using serial dilutions, with several Daphnia used at each concentration. Note that high concentrations of caffeine can be fatal for Daphnia.
The Daphnia hearts are fairly easily seen, but counting the number of beats can be difficult. Counting is easier if each heartbeat is recorded by tapping a pencil on a piece of paper and counting up the pencil marks after the specified time. In addition, cooling the Daphnia before the experiment may help slow their heart rate: heart rate is highly temperature dependent. A webcam above the eye piece of the microscope to project an image of the slide onto a large screen may also help with counting. There are videos available on the Internet that can be used to help students distinguish between the Daphnia heart and gills.
Foster, in the Journal of Biological Education (1997) 31: 253–5, provides a method using a stroboscope to freeze the motion. Use of the stroboscope may overcome the problems of counting faster heart rates. However, we would not recommend this method. Positioning the light sources and strobe is tricky. It is very difficult to freeze the motion and viewing with a strobe light can cause eye strain and dizziness. A simpler approach is to count the rate at which the legs beat. This rate is proportional to the rate at which the heart beats.
A dissecting microscope with a light source under the stage works well for this experiment. To prevent the Daphnia from overheating while on the microscope turn off the microscope light between observations and use a heat sink.
Using pond water/Daphnia culture solution is recommended for both the control group and to dissolve the caffeine as this may give more valid results and be less stressful to the Daphnia. In distilled water the heart rate may rise due to lack of oxygen.
In the trial of the experiment caffeine was used at 0.1% and 0.5% w/v with no ill effect. At 1% the Daphnia stopped swimming after 5 minutes.
It is suggested that a ‘blind’ study is done. This means that the person counting the heart rate is unaware as to whether the Daphnia is in water with or without caffeine. It has been shown that observer expectations influence the result.
It is difficult to get clear-cut results from this experiment and significant differences between treatments may not be found. The sets of results below indicate the sorts of results that can be expected. It should be impressed upon students that it does not matter if they do not get differences between treatments. Indeed, the experiment provides a good opportunity to focus on the critical evaluation of the technique used. Published results (see the weblinks) report a slowing of heart rate by a maximum of 20% at 15–20 mM caffeine. The control mechanism is unknown.
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Activity 1.27 Teacher Sheet Core Practical
Experiment 1 Daphnia were cooled on ice before the experiment. Beakers containing Daphnia in pond water were put on ice for about half an hour. This had the effect of slowing the heart rate and thus facilitating counting. The temperature of the pond water in which the Daphnia were swimming fell to about 5 °C.
A single Daphnia was placed in a beaker containing test solution for 5 minutes: either pond water, or pond water + 0.5% caffeine. After the 5 minutes, the Daphnia (in a few drops of test solution) was transferred to the slide for measurement of heart rate. Each individual was counted for 4 × 30 seconds. A blind counting method was used.
Overall means:
Caffeine – 173 beats per minute
Control – 172 beats per minute
There were no immediately observable ill effects of caffeine at this concentration (0.5% w/v).
Experiment 2 The experiment was conducted at room temperature. A single Daphnia was transferred to the slide. A paper towel was used to remove the pond water from the slide. A few drops of test solution – either pond water or pond water + 0.5% caffeine – were dripped onto the Daphnia. The clock was started immediately and the heart rate recorded for 15 seconds at 2, 4, 6, 8 and 10 minutes. A webcam was used to facilitate counting.
The results from the two experiments do not show that caffeine increases heart rate in Daphnia.
Treatment Heart rate/beats 30 s–1 Mean for individual
beats min–1
Trial 1 Trial 2 Trial 3 Trial 4 Mean
Caffeine 87 85 81 88 85 170
Caffeine 83 84 78 82 82 164
Caffeine 84 86 86 84 85 170
Caffeine 89 91 93 99 93 186
Caffeine 86 87 90 90 88 176
Control 62 70 73 74 70 140
Control 81 101 - - 91 182
Control 88 75 74 85 81 162
Control 93 98 98 100 97 194
Control 89 91 85 94 90 180
Table 1 Results for Experiment 1.
Number of heartbeats in 15 seconds
Length of time in solution/minutes 2 4 6 8 10
Treatment Caffeine 49 53 49 44 48
Caffeine 54 54 57 51 55
Caffeine 54 59 55 61 64
Caffeine 59 65 64 68 62
Mean 54 58 56 56 57
Control 57 55 59 50 58
Control 58 60 54 58 60
Control 56 56 58 57 59
Control 60 64 61 66 62
Mean 58 59 58 58 60
Table 2 Results for Experiment 2.
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Activity 1.27 Teacher Sheet Core Practical
Purpose To investigate the effect of caffeine on the heart rate of Daphnia (water fleas).
Caffeine Caffeine is produced by plants as an insecticide. Cocoa in South America, coffee in Africa and tea in Asia have all been used for hundreds of years to produce ‘pick me ups’ containing caffeine. These days caffeine is also used as a flavour enhancer in a wide range of cola and other soft drinks. In addition, it has medicinal uses in aspirin preparations and is found in weight-loss drugs and as a stimulant in students’ exam-time favourites like PRO-PLUS® and Red Bull®.
In humans, caffeine acts as a stimulant drug, causing increased amounts of stimulatory neurotransmitters to be released. At high levels of consumption caffeine has been linked to restlessness, insomnia and anxiety, causing raised stress and blood pressure. This can lead to heart and circulation problems.
Procedure
You need
Culture of Daphnia (water fleas)
Three cavity slides
Three dropping pipettes
Distilled water
Caffeine solution
Cotton wool
Pipettes
Test tubes
Stopclock Figure 1 Daphnia.
Paper towels or filter paper
Microscope
1 Place a few strands of cotton wool on a cavity slide; this will help restrict the movement of the water flea. Using a pipette, transfer one large water flea to a cavity slide. Remove the water from around the water flea using filter paper, then add one or two drops of distilled water or pond water. Use as much water as you can and do not use a cover slip. Together these precautions will help maintain sufficient oxygen supply to the flea. View the water flea under low power. Focus on its heart, which can be seen through its translucent body. The location of the heart is shown in Figure 1.
2 Use a stopwatch to record the number of heartbeats per minute. This is made easier by working in a pair, with one person counting beats while the other person tells them the time period. Tap a pencil on a piece of paper and count up the pencil marks at the end of the time period. Record the heart rate at intervals of 2 minutes over a 10 minute period. It is a good idea to do a ‘blind’ study to avoid bias in the results. The person counting the heartbeats should be unaware as to whether the Daphnia is in water or water with added caffeine.
3 Repeat the procedure using other water fleas from the culture solution and fresh, clean slides. Replace the water with caffeine solution. Repeat the procedure using several different concentrations of caffeine.
4 Record your results in a suitable format and present them in an appropriate graph. 5 Compare the treatments and try to explain the effect of each treatment on the heart rate. 6 Comment on the validity of your study. For example, would it have been better or worse to use
the same Daphnia throughout the study? 7 If time permits, you could also look at the effect of other chemicals, for example, ethanol, on the
heart rate.
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Activity 1.27 Technician Sheet Core Practical
DOES CAFFEINE AFFECT HEART RATE?
Purpose
To investigate the effect of caffeine on the heart rate of Daphnia (water fleas).
This is an activity that students may plan themselves. There is also a support sheet giving a suggested method. The list below gives the apparatus and approximate quantities needed for the suggested method. However, students may ask for things outside of this list.
SAFETY
Important! Stroboscopes can trigger epileptic fits in some people. Anyone known to be susceptible should be warned.
Background lighting should be retained and exposure times minimised.
Requirements per student or group of students
Notes
Culture of Daphnia Daphnia may be killed by chlorine in tap water. Any tap water used should be left to stand for 24 hours first to let the chlorine dissipate.
Allow at least nine Daphnia per student or pair. They should be unharmed by the activity, but may need too long to recover after the caffeine to use the same one for different concentrations in the same practical. They can be bought from an aquarist or Blades Biological Supplies.
To catch them use a plastic pipette with the tip cut off to make it wider. Goldfish enjoy disposing of Daphnia.
Container for ‘used’ Daphnia This will stop them getting mixed up with the ‘fresh’ ones.
Six cavity slides Students can wash and reuse the slides if needed.
Approximately 5 cm3 caffeine solution (0.5%)
Dissolve 0.5 g caffeine in 100 cm3 water. Instant coffee can be used.
Make up the solution with culture water or distilled water.
Students will need to dilute this to make weaker solutions. If time is limited it may be easier to provide made-up solutions of 0.25%. (Consult with the teacher/lecturer – they may prefer to use more concentrations, for example, 0.1%, 0.2%, 0.3%, 0.4% if time permits.)
Cotton wool Students will only need a small amount – about as much as is in a single cotton wool ball will supply the whole class. They put a few strands on the slide to stop the Daphnia moving.
Three dropping pipettes
5–10 cm3 distilled water or water from the Daphnia culture
For adding to the Daphnia during the experiment.
Test tubes/small beakers For students to collect or mix their caffeine solutions in. They will need more if they are doing more concentrations.
Small measuring cylinder or 5 cm3 syringe
For making dilutions of caffeine solution.
Approximately 100 cm3 distilled or pond water
For making dilutions of caffeine solution.
Amount required will depend on the dilutions made.
Stopclock
Paper towels or filter paper
Microscope For use at low power. Some centres find that it is useful, if available, to use a microscope-mounted video camera to show students the heart.
Stroboscope If this is available it can be used to get a more accurate measure of how fast the heart is beating, but is not recommended.
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Topic 1 Lifestyle, Health and Risk Exam-style end-of-topic test
Instructions
Answer all questions in the spaces provided – there may be more space than you need.
Show your working in any calculation questions and include units in your answer where appropriate.
You may use a scientific calculator.
In questions marked with an asterisk (*), marks will be awarded for your ability to structure your answer logically showing how the points that you make are related or follow on from each other where appropriate.
Some questions must be answered with a cross in a box (). If you change your mind about an answer, put a line through the box () and then mark your new answer with a cross.
Information
The total mark for this paper is 35.
The marks for each question are shown in brackets – use this as a guide as to how much time to spend on each question.
Advice
Read each question carefully before you start to answer it.
Try to answer every question.
Check your answers if you have time at the end.
1 (a) A variety of factors can contribute to a person’s risk of developing coronary heart disease (CVD); these can be a mixture of controllable and non-controllable risk factors.
(i) State two controllable risk factors for CVD. (2)
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(ii) State two non-controllable risk factors for CVD. (2)
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(b) If excess carbohydrates are eaten they are stored. (i) Below are four carbohydrates found in animals and plants. Put a cross in the box to
indicate which molecule is used for storage in animal cells.
A □ Starch
B □ Galactose
C □ Glycogen
D □ Sucrose (1)
(ii) Name the type of chemical reaction that occurs when this storage carbohydrate is created from glucose molecules. (1)
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Topic 1 Lifestyle, Health and Risk Exam-style end-of-topic test
1 of
(c) Explain how people could use obesity indicators to reduce their risk of coronary heart disease. (4)
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(Total for question 1 = 10 marks)
2 (a) Although there is a constant movement of blood through the chambers of the heart, the heart muscle has its own supply of blood vessels.
(i) Name the blood vessels supplying the heart muscle with blood. (1)
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(ii) Explain why the heart muscle must have its own blood supply. (2)
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(b) Name, in the correct sequence, which heart chambers, heart valves and blood vessels a drop of blood would pass through as it flows out of the right atrium until it reaches the aorta. (3)
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Topic 1 Lifestyle, Health and Risk Exam-style end-of-topic test
(c) Describe the benefits and risks of antihypertensives used in the treatment of cardiovascular disease. (3)
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(Total for question 2 = 9 marks)
3 Researchers at Virginia Commonwealth University in the USA have developed a bandage made entirely from fibrinogen molecules. Pre-clinical trials are being carried out on the new type of bandage.
(a) Describe the role of fibrinogen in blood clotting. (3)
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(b) Suggest one advantage of the new type of bandage. (1)
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Topic 1 Lifestyle, Health and Risk Exam-style end-of-topic test
4 A study was carried out in a group of people on the number of cigarettes smoked per day and the risk of getting of lung cancer. The results are shown in the graph below.
(a) (i) Put a cross in the box to indicate what can be concluded from the graph. (1)
A □ Correlation between smoking and lung cancer but no evidence that smoking causes lung cancer
B □ No correlation between smoking and lung cancer but evidence that smoking causes lung cancer
C □ Correlation between smoking and lung cancer and evidence that smoking causes lung cancer
D □ No correlation between smoking and lung cancer and no evidence that smoking causes lung cancer
(ii) State two additional pieces of information that would help assess the validity of the conclusions made from this study. (2)
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Topic 1 Lifestyle, Health and Risk Exam-style end-of-topic test
*(b) Graph A below shows some results from a 1950s study on over 12 000 men to show the effect of fat on death from coronary heart disease (CHD). Graph B shows the results of a 1980s study on over 12 000 men to show the effect of cholesterol levels on death from all Cardiovascular disease, CHD and strokes.
Some studies have claimed that saturated fats and the resulting increase in blood cholesterol cause CHD.
Evaluate this claim and how far the evidence in graphs A and B support the claim. (9)
Graph A Graph B
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(Total for question 4 = 12 marks)
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Topic 1 Lifestyle, Health and Risk Mark Scheme for Exam-style end-of-topic test
General information Mark schemes should be applied positively. Candidates must be rewarded for what they have shown they can do rather than be penalised for omissions.
Where some judgement is required, mark schemes will provide the principles by which marks will be awarded and exemplification/indicative content will not be exhaustive.
Crossed out work should be marked unless the candidate has replaced it with an alternative response.
Question number Mark
1(a)(i) High blood {cholesterol / Low density lipoprotein / LDL levels}; High saturated fat intake; High salt intake; High levels of radicals in the diet; Excessive alcohol intake; Lack of exercise; High blood pressure; Stress; Obesity; Smoking; (2)
1(a)(iii) Age; Genetic predisposition; Gender; (2)
1(b)(i) C; (1)
1(b)(ii) Condensation; (1)
1(c) Calculate obesity indicator; BMI / Waist-to-hip ratio; Details of measurement; Threshold for obesity / healthy weight / eq;
Change of lifestyle / change diet / have a low fat diet / reduced intake of cholesterol / do more exercise; To reduce BMI / maintain healthy BMI / reduce risk of obesity / reduce risk of CVD; (4)
(Total for Question 1 = 10 marks)
2(a)(i) Coronary arteries; (1)
2(a)(ii) Every heart muscle cell needs to be close to a capillary;
For diffusion {to provide sufficient {oxygen / glucose/ nutrients} / to remove {waste products / carbon dioxide}};
Walls of atria and ventricles have too small a surface area to allow diffusion of substances to / from all heart cells; (2)
2(b) Atrioventricular / tricuspid valve (3) Right ventricle Pulmonary artery Pulmonary vein Left atrium Atrioventricular / bicuspid valve Left ventricle
1 mark for correct order of heart chambers, 1 mark for correct order of blood vessels and 1 mark for correct position of valves in sequence of events.
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Topic 1 Lifestyle, Health and Risk Mark Scheme for Exam-style end-of-topic test
2(c) Benefits: {Reduced /less} {vasoconstriction / constriction of blood vessels}; {Reduced / lower / eq} blood pressure; Reduced risk of CVD; Risks: Side effects; Any examples given for a named antihypertensive; (3)
(Total for Question 1 = 9 marks)
3(a) Fibrinogen to fibrin; Mesh of insoluble fibrin fibres forms; Traps blood cells / forms a clot; (3)
3(b) Speeds up clotting process; More fibrinogen available to convert to fibrin; Bandage forms part of clot so does not need to be removed; (1)
(Total for Question 1 = 4 marks)
4(a)(i) A ; (1)
4(a)(ii) sample size ; location of the study ; gender balance of subjects ; medical history of subjects ; age of subjects ; information about lifestyle / diet of subjects ; (2)
*4(b) Answers will be credited according to candidates’ deployment of knowledge and understanding of material in relation to the qualities and skills outlined in the generic mark scheme.
The indicative content below is not prescriptive and candidates are not required to include all the material which is indicated as relevant. Additional content included in the response must be scientific and relevant.
Candidates are expected to reach a decision/judgment on whether saturated fats and the resulting increase in blood cholesterol cause CHD. ● Idea that saturated fat/cholesterol does increase blood cholesterol levels ● Causal link has been identified; ● Cholesterol role in atherosclerosis ● Other factos contribute to risk of developing CHD / examples of other risk factors ● Multifactoral nature of CHD ● Both graphs support correlation between fat and increased risk ● Graph B indicates correlation between cholesterol and CHD ● Low cholesterol slightly higher risk of death from graph B/1980s study ● Data does not support causal link ● Idea that calories from fat in graph A give no indication of type of fat so weaker
evidence ● Studies only involve men so conclusion only be applied to men ● Idea about quality of evidence/ both have large sample size
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Topic 1 Lifestyle, Health and Risk Mark Scheme for Exam-style end-of-topic test
Level Mark Descriptor
0 No rewardable material
Level 1 1–3 Demonstrates isolated elements of biological knowledge and understanding.
Provides little or no reference to a range of scientific ideas, processes, techniques and procedures.
Scientific argument may be attempted, but fails to link biological concepts and/or ideas in order to support decision/conclusion. Limited attempt to address the question.
170
Level 2 4–6 Demonstrates adequate biological knowledge and understanding with selection of some biological facts/concepts to support the argument or decision/conclusion being made.
Scientific reasoning occasionally supported through the linkage of a range of scientific ideas, processes, techniques and procedures.
Scientific argument is partially developed. Attempts to synthesise and integrate relevant knowledge with linkages to biological concepts and/or ideas, leading to a notional scientific argument or decision/conclusion based on evidence.
Level 3 7–9 Demonstrates comprehensive knowledge and understanding by selecting and applying relevant knowledge of biological facts/concepts to support the argument or decision/conclusion being made.
Scientific reasoning supported throughout by sustained linkage of a range of scientific ideas, processes, techniques or procedures.
Scientific argument is well developed and logical. Demonstrating throughout the skills of synthesising and integrating relevant knowledge with consistent linkages to biological concepts and/or ideas, leading to nuanced and balanced scientific argument or decision/conclusion based on evidence.
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Thinking Bigger Notes and Guidance for Teachers
Overview At the end of each chapter in the Student Book is a summary spread entitled Thinking Bigger. These spreads all follow the same format and although the content of each one is different, the approach and objectives are the same. The Thinking Bigger feature can be used with your students in a variety of ways: in class, for homework, in group work and independently. The guidance below gives some suggestions for how to do this and explains the purpose of each aspect of the spread.
Each spread is based broadly on the content of the chapter that students have just completed, and also draws on prior learning from earlier in the course or from GCSE. It points towards future learning and broader and less familiar contexts.
Purpose and process The purpose of the Thinking Bigger feature is to help students to:
bring together aspects of their learning from across the course as a whole
understand their learning in a wider context
apply knowledge and skills to unfamiliar aspects of science or new contexts
think in a bigger way and more holistically about the science they are learning.
This is achieved by taking students through a process of reading, analysing and digesting information from a range of real-life sources, supporting them with thinking critically about those sources, then using that thinking to complete a range of questions and tasks.
Each Thinking Bigger spread requires students to:
read real-life scientific writing that is directly relevant to the course and the specification
analyse both the content and the style or features of the writing
think critically about the nature of what they have read and the issues, problems and challenges that may be raised
answer questions and complete written tasks that draw on what they have read and how they have thought about it
understand where they are in their own learning journey and how different aspects of learning piece together.
Exploiting the Thinking Bigger feature in teaching and learning
1 The source material
Each spread begins with a piece of real-life scientific writing. This may be an extract from a scientific journal, a research paper or a website, along with any relevant images and data. The source of the material is always given, and where the writing is extracted from a longer item, students can be encouraged to read the full item for themselves in order to extend their wider reading.
Teaching and learning suggestions:
Ask students to read the extract and make a list or table of prior learning that is in any way relevant to the subject of the extract.
Ask students to underline or list all specialist terminology that is used and find definitions for any terms they do not know.
Refer students to the full item and have them read it as background and preparation.
Refer students to other items from the same source in order to extend their reading further.
Ask students to find one or more pieces of writing on the same subject for themselves from library journals, the internet and other sources.
SAMPLE MATERIA
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SAMPLE MATERIA
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Salters-Nuffield Advanced Biology Resources
© University of York, developed by University of York Science Education Group. Page 2 of 3 This sheet may have been altered from the original.
Thinking Bigger Notes and Guidance for Teachers
2 Questions and critical thinking
Each written extract is followed by a series of questions or problems. The questions on the page are designed to help students think critically about what they have read, and from this to develop critical approaches to all scientific material that they encounter. The questions are not intended to be exhaustive, but rather act as a stimulus to analysis, discussion and wider thinking. Many of the questions lend themselves to whole class discussion as well as to individual written work.
Teaching and learning suggestions
Students could be asked to work through the questions independently and make notes to prepare for class discussion or group work.
Divide the class into groups; have all groups consider the same question(s) and feed back to the whole class in turn.
Where time is short, allocate different questions to each group and have each group feed back to the whole class as a carousel.
Prompt groups to challenge each other to explain, give examples and justify their responses, and to award each other points or marks.
Have each group draw up a spider diagram on a large sheet of paper to show how learning from elsewhere in the course is relevant to the subject matter of the article. Groups compare diagrams until a single, definitive diagram is agreed upon.
Prompt students to draw on their learning from other science subjects and more widely, to help them in their process of deconstructing, analysing and discussing the source material and in answering the questions.
3. Notepad feature
The notepad feature appears on the page whenever there are hints and support that will be particularly useful or relevant for students while working through the spread. This may include definitions of key command words, or extra help with how to approach a particular piece of writing, or guided support with critical thinking.
Teaching and learning suggestions
Students can be asked to keep their own scrapbook of helpful hints and key terms. Where students have access to a digital version of the Student Book they can use annotation tools to add their own notes to the spreads as they work through them.
4. Activity and written answers
Each spread includes either a substantial activity or one or more questions requiring longer, written answers. These follow on directly from the questions designed to stimulate thinking and analysis, and encourage students to use what they have read and how they have thought about that reading, to help them with constructing writing of their own, or working through a solution to a similar problem. The tasks and activities are self-explanatory and many are open-ended so that students may differentiate themselves by what they do and how well they construct their responses.
Most of the tasks can be completed as a written response on an individual basis. Below are some suggestions for introducing variety and encouraging students to exploit fully the content, style and broad understanding of what they have read.
Teaching and learning suggestions
Ask students to make a spider diagram or table of all aspects of prior learning, both from earlier in the course and from GCSE, that they think could be relevant to the task. For each point, students should identify what the learning is, how it is relevant, and how they intend to use it in completing the task or activity.
Think about different formats for written responses. For example, students could be asked to present their work as an oral presentation to the rest of the class, with accompanying written slides and visuals.
SAMPLE MATERIA
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SAMPLE MATERIA
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Salters-Nuffield Advanced Biology Resources
© University of York, developed by University of York Science Education Group. Page 3 of 3 This sheet may have been altered from the original.
Thinking Bigger Notes and Guidance for Teachers
In addition to, or instead of, the tasks on the spread, ask students to write an article for the same publication as the source material on a similar or related subject.
Ask students to write a letter to the publisher of the source material in which they take an opposing view to the author, or question the validity or ethics of the science or the scientific process, or conversely in which they offer their support, explaining why and justifying their stance.
Students could construct their own scientific journal, selecting articles and letters from among the group, and adding to these as they complete each successive Thinking Bigger spread until they have something they can publish for the school library.
5. Learning timeline
Across the bottom of each Thinking Bigger spread is a timeline that represents the learning journey for the relevant section of the course, either year 1/AS or year 2 of the full A Level. The timeline shows all numbered sections of the course book, with the colour of each section in the timeline corresponding to the colour of that section of the book. An icon reminds students exactly where they are up to in the course. Sections of the course that contain knowledge, understanding and skills that are relevant to the spread are shown in colour. Other sections are shown in grey.
Teaching and learning suggestions
Ask students to read the title of the article, then consider the timeline. What elements of their prior learning from the highlighted sections of the course could be relevant to the article? List them. Read the article then identify how each element of prior learning relates to the subject of the article.
Rate each element of relevant prior learning from the most relevant to the least relevant. Justify the ratings given.
As revision towards the end of the course students should be encouraged to come back to each Thinking Bigger spread and work through the questions and tasks again, taking account of all aspects of relevant learning that occurred at a later point in the course, i.e. beyond the point of the ‘you are here’ icon.
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