CP4-Pollen Tube Growth

Question 1

Objectives - investigate the effect of sucrose concentration on pollen tube growth

Answer 1

Objectives:

• observe the growth of pollen grains
• learn how to carry out dilutions

Question 2

Risks?

Answer 2

• glass slides can break
• mounted needles can pierce skin
• if you allergic to pollen you should take appropriate precautions, eg wash hands regularly, use antihistamines, or just observe the practical

Question 3

Method?

Answer 3

• serially dilute 5 concentrations of sucrose from a 1 mol solution
• label one Petri dish per concentration and place moist filter paper inside
• label one microscope slide with the concentrations of sucrose and place a few drops of sucrose in the middle
• using a grown anther from a mature plant, and use a mounted needle to drop pollen onto each slide, using the same flower
• place open slides in Petri dish and cover with lid
• record measurements every lesson for a week, recording how many hours it’s been since the start of the experiment, in a table, by putting the slide under a microscope

Question 4

Variables?

Answer 4

IV-sucrose concentrations
DV-length of pollen tube
CV-same flower, improves the validity of results because the maturity and species are controlled and the results are comparable