Labs to know-1 labs labs question labs labs

labs

1. What are the prescribed labs?
(6 SL & 7 HL)
6 from Core material / 1 from AHL

2. © International Baccalaureate Organization 2007
1) Calculation of magnification of
drawing, actual size of structures from
drawings or micrographs
Core Topic 1.1
Page 2

3. © International Baccalaureate Organization 2007
Memorize the formula:
Page 3

4. © International Baccalaureate Organization 2007
Memorize:
Conversion factors:
1mm = 1000 µm
1 µm = 1000 nm
1 mm = 10
6
nm ( or 1,000,000 nm)
Appropriate units to use:
Bacteria (prokaryotes) are in µm.
Viruses are in nm.
Page 4

5. © International Baccalaureate Organization 2007
Example problem:
Watch Stephanie Castle’s 5 minute
tutoring!
We also went over several problems
in Skills packet Topic 1.
Page 5

6. © International Baccalaureate Organization 2007
2) Estimation of osmolarity in tissues
Core Topic 1.4
Page 6

7. © International Baccalaureate Organization 2007
First you need to understand…
Osmosis
Osmolarity
Page 7

8. © International Baccalaureate Organization 2007
Next you’ll want to memorize these definitions:
Hypertonic= higher solute concentration
Isotonic= equal solute concentration
Hypotonic= lower solute concentration
Also remember, water always moves…
From HYPOTONIC to HYPERTONIC!
Page 8

9. © International Baccalaureate Organization 2007
Next, watch this!
Stephanie Castle’s reenactment of the
potato lab we did! (it should look
familiar)
Remember: where the line crosses the
x-axis (at zero) is the osmolarity (or
sugar concentration) of the potato. Be
precise!
Page 9

10. © International Baccalaureate Organization 2007
3) Investigation of a factor affecting
enzyme activity
Core Topic 2.5
Page 10

11. © International Baccalaureate Organization 2007
First, you should know a little about:
Enzymes & substrates
Factors that affect enzyme activity
Designing an enzyme activity experiment
Page 11

12. © International Baccalaureate Organization 2007
Then watch this…
Stephanie Castle’s explanation of the graphs for
temp, pH & substrate concentration & their effects on
enzyme activity.
Know how to explain the different parts of the graphs
like Stephanie!
Page 12

13. © International Baccalaureate Organization 2007
4) Separation of photosynthetic pigments
by chromatography
Core Topic 2.9
Page 13

14. © International Baccalaureate Organization 2007
First, know this…
Chromatography= technique of
separating the components of a mixture
Page 14

15. © International Baccalaureate Organization 2007
Then look at this…
Bio Ninja’s explanation of plant
chromatography& calculation of Rfvalues.
Memorize Rfformula:
Page 15

16. © International Baccalaureate Organization 2007
Know how to calculate the Rf value (has
no units & expressed as a decimal):
Page 16

17. © International Baccalaureate Organization 2007
5) Creating a sealed mesocosm
Core Topic 4
Page 17

18. © International Baccalaureate Organization 2007
First know this slide:
Ecosystem= a community & its abiotic factors
Page 18

19. © International Baccalaureate Organization 2007
Mesocosm= an enclosed & self-sustaining
experimental environment or ecosystem
Page 19

20. © International Baccalaureate Organization 2007
Know this…
Energyis not recycled, so you have to constantly
supply it. (initial energy is sunlight; lost as heat)
Nutrientsare recycled, so you only have to supply
them initially. (e.g. H
2O, C, H, O, N, P)
Page 20

21. © International Baccalaureate Organization 2007
Then watch this…
Alex Lee’s explanation of a mesocosm.
IB Bio students’ mesocosm project.
Page 21

22. © International Baccalaureate Organization 2007
6) Monitoring of ventilation at rest and
after mild and vigorous exercise
Core Topic 6.4
Page 22

23. © International Baccalaureate Organization 2007
Check out these Bio Ninja explanations:
Measuring ventilation
Lung Capacity
Page 23

24. © International Baccalaureate Organization 2007
Watch these related Stephanie Castle videos:
Explain the need for a ventilation system
Explain the mechanism of ventilation
Changes in tidal volume & ventilation rate
Page 24

25. © International Baccalaureate Organization 2007
7) Measurement of transpiration rates
using potometers (HL only)
AHL Topic 9.1
Page 25

26. © International Baccalaureate Organization 2007
First, know this slide…
Transpiration= evaporation of water from leaves &
stems of plants, after absorption by roots
1
st
step = evaporation of water
4 environmental factors that affect rate:
•Light
•Wind
•Temperature
•Humidity
Page 26

27. © International Baccalaureate Organization 2007
Know how to explain HOW these factors affect
transpiration rate…
Page 27

28. © International Baccalaureate Organization 2007
How to measure transpiration rate:
Page 28

29. © International Baccalaureate Organization 2007
Review transpiration…
Bio Ninja’s explanation of transpiration
Bio Ninja’s explanation of factors that affect
transpiration
Page 29