1. Complete your name and student number at the top.
2. Answer the questions below. 6 marks worth 6%.
Q1. RESULTS – these are the data you have obtained from the microscopy images. (1 mark)
You must show your working
...
1. Complete your name and student number at the top.
2. Answer the questions below. 6 marks worth 6%.
Q1. RESULTS – these are the data you have obtained from the microscopy images. (1 mark)
You must show your working to gain full marks.
Total number of chloroplasts per cell from 6 independent counts (In equation 1, this value is
substituted for M)
Cell #1
Total
Chloroplasts
Cell #2
Total
Chloroplasts
Cell #3
Total
Chloroplasts
Cell #4
Total
Chloroplasts
Cell #5
Total
Chloroplasts
Cell #6
Total
Chloroplasts
19 20 18 32 27 34
Average number of chloroplasts (M) = (19+20+18+32+27+34)/5 = 25 chloroplast/cell
Determine the average diameter of the chloroplasts in micrometres (m) from 6 different
chloroplasts. Calculate the average radius in metres (In equation 1, this calculated value is
substituted for r).
Chloroplast 1 2 3 4 5 6
Diameter
(µm) 4 5.5 6 5.5 4.5 5
Average (mean) diameter in µm (4+5.5+6+5.5+4.5+5)/6 = ~5.08 = 5 µm
Average (mean) radius (r) in µm 5/2 = 2.5 µm
Convert r to SI units in m (metres) 2.5 x 10-6 m
This study source was downloaded by 100000844708667 from CourseHero.com on 11-03-2022 10:43:14 GMT -05:00 Practical 5 Racing Chloroplasts 1
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LQB182 ONLINE LABORATORY WORKSHEET QUESTIONS WITH
COMPLETE SOLUTIONS
LQB182 Online Laboratory Worksheet
The average velocity of the chloroplasts in micrometres per second (m per second) was recorded
from 6 independent measurements (6 different chloroplasts) (In equation 1, this calculated value is
substituted for V)
Chloroplast 1 2 3 4 5 6
Velocity (µm/s)
4 5 5 6 8 2
Average velocity (V) in µm/s ((4+5+5+6+8+2) / 6) = 5 µm/s
Convert r to SI units in m/s (5 / 1x106
) = 5.0 x 10-6 m/s
Q2. Calculations (4 marks total)
Energy expended to drive cyclosis in a single chloroplast cell
Use the formula (Equation 1) derived in the practical module (included below) to calculate the
energy expended to bring about cyclosis in each of the cells of the leaves you have been observing.
Don’t forget units! Use brackets around each variable when performing your calculations.
You must show your working to gain full marks.
Equation 1: 6πrnV2M (Js-1 Cell-1 for a cell containing M chloroplasts)
π 3.14 (pi)
r
2.5 x 10-6 m (your mean radius)
n 10-2 Ns m-2 (viscosity for cytoplasm)
V
5.0 x10-6 m/s
M 25 (your mean chloroplast number)
Working:
= 6 x 3.14 x (2.5 x 10-6) x (10-2) x (5.0 x 10-6)
2
x 25
= 18.84 x (2.5 x 10-8) x (2.5 x 10-11) x 25
= 2.944 x 10-16
Eq 1 Answer = 2.944 x 10-16 Joules per second per cell (Js-1 Cell-1)
This study source was downloaded by 100000844708667 from CourseHero.com on 11-03-2022 10:43:14 GMT -05:00 Practical 5 Racing Chloroplasts 2
https://www.coursehero.com/file/68559990/LQB182-Prac-5docx/
LQB182 Online Laboratory Worksheet
You now need to calculate the number of molecules of ATP required to drive cyclosis of
chloroplasts in a cell. That is – how many ATP molecules are converted to ADP to perform cyclosis
in one cell?
You must show your working to gain full marks.
Equation 2: Divide the an
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