Prac Techniques

Question 1

When referring to confidence of results what must you talk about

Answer 1

Repeating
Calc mean
Identify anomalies
Use stats test

Question 2

when they say evaluate what does this mean

Answer 2

give both sides of the argument

Question 3

examples of issues with validity

Answer 3

no method
control factors that may effect (give example, conc, temp, mineral availability light intensity)
no control group
no error bars
no repeats

Question 4

how to do potometer prac

Answer 4

dry leaves
cut shoot slanted under water
control temp
light intensity
surface of leafs
measure distance travellled by air bubble
tells u uptake of oxygen and rate of transpiration

Question 5

how to do potometer prac

Answer 5

dry leaves
cut shoot slanted under water
control temp
light intensity
surface of leafs
measure distance travellled by air bubble
tells u uptake of oxygen and rate of transpiration

Question 6

potential errors in potometer prac

Answer 6

leak in apparatus
shoot not cut under water
error in readin meniscus

Question 7

when using this technique what is assumption

Answer 7

that rate of uptake of water equals transpiration

Question 8

describe and explain precautions needed to set up this to ensure no air present

Answer 8

cut stem under water and set up apparatus underwater
so no air can enter stem/shoot, air bubble could block xylem we need to ensure continuous flow

do not allow bubble to move too far use syringe to move the bubble

place open end of shoot in water ap no air introduced

keep shoot still to avoid breaking seal