Posts Tagged ‘chromosome’

Kit Review: Ward’s Chromosome Extraction & Analysis

October 7, 2009

Ordering and Receiving:

The kit arrived on time and in good condition.  The Ward’s salesperson was friendly and informative.  There is an included coupon for the Drosophila virilis culture, which can be redeemed by mail or phone.  Service on this was also prompt.

Initial Impressions:

The package is appropriate for the material and clearly labeled.  The contents of the package were listed in the instructors guide, and were easily inventoried.

What the kit includes:

  • 72 microscope slides
  • 100 cover slips
  • 5 dissection probes
  • 5 pairs fine dissection forceps
  • 15ml bottle stain
  • 15ml bottle 8% HCl
  • 15ml bottle mounting media (Piccolyte II)
  • 6 3ml drop bottles
  • Drosophila virilis Salivary Gland Cell Reference slide
  • Copymaster set of student handouts
  • teacher’s guide
  • coupon for Drosophila virilis culture

All in all, I’m impressed with what the kit includes.  I particularly like the reference slide, which makes a nice addition to our school’s collection.  It would be nice to have more forceps and probes, but I imagine most people have some of them already.

Comments on the instructors guide and student handouts:

I think the accompanying documentation is pretty good.  The student handouts have good background, and there are questions to verify that students assimilate the material.  Instructions are clear and laid out in a sensible manner.  The instructor’s guide suggests that a maximum of 5 students dissect at any given time due to logistics and difficulties in dissection.  They suggest that the dissections be staggered over a few days.  This will also give the larvae time to mature.

It would be very nice to have labeled color pictures of the dissection process.  Perhaps they could be included on CD-ROM or be made available for download via the Ward’s website.  This would aide tremendously in improving the success rate of dissection.

Comments on the materials:

I was pleased with all of the materials from a quality perspective.  Ward’s did not skimp on slides, covers, or solutions.  The included reference slide is also quite nice.  Consider purchasing extra forceps and probes if you do not already have some.

You will need a dissecting microscope for every station, and it would be nice if it can light both from above and below the specimen to better visualize the anatomy.  You will also need compound microscopes to view the resulting slides.  You can definitely visualize the chromosomes at 400x, but 1000x is definitely preferable.

Summary:

The Good:

This is a solid kit, that provides everything but the microscopes needed to extract and visualize giant fruit fly chromosomes.  Along the way, students get to produce slides of their work, and participate in small-scale dissection.  If you want, you can even maintain the culture, and give students experience working with a key model organism.

The Bad:

By necessity, there is a great deal of trial and error involved in successful salivary gland extraction.  There is simply no getting around this difficulty, so be prepared for some frustration.  Student results will vary wildly, but can be improved with care and practice.

The Ugly:

Not too much is ugly.  There are some significant infrastructure demands in terms of microscopes.  You need decent microscopes of both types.  Also, the kit itself is not particularly cheap, though it is reasonable for what you get in it.

Over-all:

I will continue to either refill or repurchase this kit in the years to come.  I think it is a good value, and provides a positive though challenging experience.

Link to kit at Ward’s:

http://wardsci.com/product.asp?pn=IG0009913&bhcd2=1254980107

Good website for Drosophila dissection and chromosome extraction

October 7, 2009

Today, I found a great website describing a procedure for Drosophila dissection to supplement the materials contained in the kit from Wards.  It would be great for Wards to produce a CD of similar images to go along with their kit.  The review for the kit is incoming soon, but for now check out this site:

http://biology.clc.uc.edu/fankhauser/Labs/Genetics/Drosophila_chromosomes/Drosophila_Chromosomes.htm

plenty of awesome information and pictures to help your students get good results from this lab.

Cheers!