Manual
Pearson IB Biology HL Laboratory Worksheets
- Course
- Institution
Manual of 48 pages for the course IB Biology at Arı Anatolian High School (worksheet)
[Show more]
3 reviews
By: beatawyszkowska • 5 year ago
By: christinebanham • 5 year ago
By: srikanntragvani • 6 year ago
Seller
Follow
lilithstudiess
Reviews received
Content preview
LABORATORYWORKSHEETS
,Chapte
C er 2: The
T effect
e of increassing
empeeraturre on carbo
te on diooxide
e outpput byy
germin
g natingg seeds
Brrief summ
mary
Loo
oking at the influence off temperaturre on the ratee of cell resp
piration as measured
m by the
t rate of CO
C 2 output. CO
C 2
sen
nsors or resp
pirometers could be used d to monitorr the level of CO2 in a sealed chamberr containing seeds. A largge
see
ed species w
works best, suuch as pea seeeds.
Aiim
eed’s rate of cell of respiration. In Part 1 of this in
To investigate the influence of temperaature on a se nvestigation
you will measuure the basal CO2 output of germinating seeds and learn the technique
t off measuring changes
c in CO
C 2
concentration using a sensor or respiroometer within a closed chhamber. In Part
P 2, you willw alter the temperature
t e of
e environmeent of these seeds
the s and measure the effect
e on the rate of CO2 output.
Va
ariables
• Independeent variable: the air (or water)
w tempe
erature.
• Dependentt variable: th
he CO2 outpu
ut during a seelected time period.
• Controlled variables: air pressure; light
l intensitty; species off seed; germination stage
e of seeds.
Th
heory
Seeeds (pea seeeds or other) are embryonic plants. A typical seed d undergoes a developmental period following
pollination and d subsequentt fertilization
n, and develoops into a veery small emb bryonic plant surrounded d by nutritio
ous
endosperm tisssue and a seed coat (testta). The seed d then goes into a dormaancy period until u the seedd coat absorrbs
waater, which in nitiates the events
e known as germinaation. Duringg germination, the embryyonic plant absorbs a
nutritive substances from the t endosperm and begins to grow; the t plant’s metabolic
m ratte is extremeely high durinng
thiis time period. Photosyntthesis has no ot yet begun (and will no ot begin untill the first tru
ue leaves of the
t plant are e
developed and d above ground), and thu us the only major
m cellularr process involving carbon dioxide that is occurrin ng
is aerobic
a cell rrespiration.
Ap
pparatus rrequired
• CO2 sensorrs and associiated hardwaare/softwaree (an alternative would be
b respiromeeters and trayys for
underwateer submersioon).
• ng seeds (pea seeds 2–3 days into geermination w
Germinatin would be ideaal).
• Respiration
n chambers (a
( sealed chaamber design metric pipette of a
ned for sensor insertion or the volum
respirometter).
• If CO2 senssors are to bee used, a wayy of increasing the temperature will be needed, such
s as electtric heating
pads.
© Peaarson Educatio
on Ltd 2013. For
F more information abou
ut the Pearson
n Baccalaureatte series pleasse visit
www.peearsonbacconline.com
,• If respirom
meters are to be used, a hotplate
h or microwave
m is necessary to
o provide diffferent increements of waater
temperature.
• Thermomeeters to measure either the
t air (senso
or method) or
o water (resspirometer method)
m temperature.
• A timing deevice.
• Optional: aapparatus to measure selected control variables, such as a baarometer forr air pressuree, light meter
for light inttensity, etc.
Sttep-by-steep method
d and proccedure
The procedurees given below
w are most appropriate
a or method of
for the senso o measuring CO2; if respiirometers are
ed, make chaanges as neeeded to acco
use ount for the different
d metthodology.
Paart 1 proced
dure: Determ
mination off the basal metabolic rate
r as refle
ected by th
he CO2 given
n off in a 2-
miinute time pperiod
• Count out and place 200 germinating seeds (more if the seed
ds are smalle
er than peas) in a respiraation chambeer
(do not insert the CO2 sensor
s yet).
• Allow this cchamber to remain with the peas forr a minimum
m of 2 minutees to equilibrrate with thee surroundingg
air temperature.
• Insert the C
CO2 sensor in
nto the respiration chammber and enssure a good stopper
s fit, and link up with
w the
hardware//software necessary to measure
m the CO
C 2.
• ore seconds as a further equilibration period (usee a timer or clock).
Wait 30 mo
• Start colleccting your CO
O2 data from
m within the sealed
s chamber and conttinue for 2 minutes.
m
• Use any other sensors or meters neecessary to collect
c any co
ontrol variab
ble data, such
h as air presssure and ligh
ht
intensity.
Maake four morre data collecction ‘runs’ (making
( a tottal of five) byy repeating the
t steps sho own above. To
T begin a data
run
n you should d return yourr 20 germinaating seeds too the originaal tray, mix th hem up, and then choosee 20 more
see
eds at rando om. Also, you
u should inveert the respirration chamb ber (i.e. with the openingg down) for at
a least 30
secconds to allo
ow the previoously accumulated CO2 to move out o of the chamb ber (CO2 is more
m dense than
t other
gasses within air and thus moves
m down, not up).
Paart 2 proced
dure: Determ
mination off the influence of an environmen
e ntal factor on
o the metaabolic rate of
o
ge
erminating ppea seeds
Your instructorr may want to
t assign groups for this lab, with eacch group bein ng responsib ble for the daata collection
n
of a specific temperature. There
T will neeed to be som
me initial plaanning by triaal and error to determine what the
mperature in
tem ncrements arre going to be.
b
You will now be increasing the temperaature of the respiration chambers
c in order to me
easure the efffects on the
ratte of cell resp
piration.
If you
y are usingg respirometters immerseed in water, you
y will be adding
a and taaking away volumes
v of water
w in ordeer
to create increasing tempeeratures to teest. You shouuld always haave a ready supply
s of hot water and a way of
scoooping out th
he water thaat is to be rep
placed. Use a bulb pipettte immersedd in the tray to
t monitor the water
temmperature.
If you
y are usingg CO2 sensorrs, you will prrobably be using
u a heatin
ng pad to control the inccreasing temperatures.
Tape a bulb theermometer tot the outsid de of the resp
piration chammber and usse that to esttimate the in
nternal
© Peaarson Educatio
on Ltd 2013. For
F more information abou
ut the Pearson
n Baccalaureatte series pleasse visit
www.peearsonbacconline.com
, tem
mperature after allowingg a suitable equilibration
e period. The temperaturre variations can be obtained by usingg
setttings on thee heating pad
d coupled with how far away
a the resp
piration cham
mber is from
m the actual pad
p (you migght
waant to use a rring stand an
nd clamp to hold
h the chamber).
You will need to
t collect fivee sets of dataa for each off the temperrature increm
ments. The data you colleected in partt 1
n be one of yyour five incrrements (as the lowest temperature). Don’t forget to collect the data forr the controllled
can
varriables durin
ng each trial and
a replicatee.
Reesults
O2 output perr time at various temperatures.
CO
Gu
uidance to
o underta
ake data processing
p g
The rate of CO2 output will need to be calculated based on the average of the
t five repliccates for eacch
mperature.
tem
Gu
uidance fo
or presenttation of p
processed
d data
An
n appropriatee graph woulld have temp perature incrrements on the
t x-axis an
nd the mean rate of CO2 output
o on th
he
y-aaxis. If a lineaar pattern is detected, a line of best fit
f should bee drawn through the five data points plotted. Erro
or
bars could be included representing eitther the rangge of data leading to each mean poin nt plotted or the standard
deviation of eaach mean point.
Co
onclusion
Base your concclusion on th
he pattern shhown on the graph. Your discussion should s be cen
ntred on thee expectation
n of
how an increasse in temperrature will afffect the ratee of cell respiiration and why.
w
Evvaluation
Loo
ok for the strengths and weaknessess of this procedure and teechnique wh
hile the invesstigation is proceeding.
Su
uggested reading
r
Chapter 2: Secttion 2.8.
© Peaarson Educatio
on Ltd 2013. For
F more information abou
ut the Pearson
n Baccalaureatte series pleasse visit
www.peearsonbacconline.com
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller lilithstudiess. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $7.49. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
62555 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy study notes for 14 years now