What's New?

About

Services

Educational
Materials

Upcoming
Events

Awards

Links

Archive

Membership



A Newsletter Exploring Science
& Biomedical Research Issues
For School Educators
Volume 1, Issue 16, Summer 2007

BioFocus Logo

page one       page two


Let's Focus on Science in the Classroom

Continued from page 1...

Instructor helping The instructors consist of veterinarians, veterinary technicians, laboratory animal technologists, microbiologists, and medical students from the Jobst Vascular Lab at the University of Michigan (See Figs. 4a & 4b). The incorporation of instructors from several areas of the biomedical field, both male and female, into this unit of study has helped to stimulate talk about research and science careers among the students at the elementary school level. There are always children who want to be a veterinarian when they grow up, and this day provides a great opportunity for them to interact with people from the animal health field and have their questions answered by them.

This "Eye Spy" event helps to promote a positive experience in the field of science at a young age and encourages science exploration in these students. The dissection of a sheep's eye at the culmination of this large unit has become one of the highlights of the year for the second graders at Pleasant Ridge Elementary School. Also, if there are any specimens left after all the classes have finished their dissections they are used to either instruct a similar class for home-schooled children, other elementary schools, or the Boy Scouts.

DID YOU KNOW?

How the Eyes See

  • Light enters the eye from the cornea.
  • From the cornea, light passes through the pupil. The amount of light is regulated by the iris, which is the colored part of the eye.
  • The light hits the clear lens.
  • It passes through the vitreous humor.
  • Light reaches the retina, where the image appears to be upside down, reversed, and two-dimensional.
  • The optic nerve sends this image to the back of the brain to an area called the occipital lobe. There the brain interprets the image as right-side-up and un-reversed. The image is also three-dimensional because of the separation of the eyes. This separation permits us to see objects from slightly different angles, which the brain fuses into a single three-dimensional picture.
Causes of Blindness
  • Diseases
  • Malnutrition: Lack of vitamin A (found in vegetables)
  • Accidents: Chemicals and sharp objects
Rods & Cones (In the Retina)
CONES
Are responsible for color vision and fine visual discrimination.

RODS
Are responsible for motion detection and night vision.

COLOR BLINDNESS
Occurs because the color-sensitive cones in the retina are either absent or do not work properly. Affects 8% of all people, usually males, and is hereditary.

BLIND SPOT
The area where the optic nerve comes off of the back of the eye and has no light receptors. That is the reason that everyone has a blind spot.

Eye Disorders
NEAR-SIGHTED
Can see close objects, distant objects are blurry. Occurs because the eyeball is too long from front to back or the cornea is curved. Since the eyeball is too deep the light rays from distant objects are focused before they hit the retina.

FAR-SIGHTED
Can see far objects, close objects are blurry. Occurs because the eyeball is too short from front to back or the cornea is too flat. That shortness causes light rays to focus behind the retina.

ASTIGMATISM
Objects both near and far are blurry. Occurs usually because the cornea has lost its spherical shape causing the light rays to have more than one point of focus when they hit the retina and creating a garbled (mixed-up) image.

The History of Eyeglasses & Contact Lenses
Salvino D'armante is credited with the first wearable glasses in 1284 in Pisa, Italy (hmmm, that's where the leaning tower is maybe their glasses were crooked!). Before that polished rock crystals were set on top of readings to magnify the writing (earliest found 1000A.D. in Nineveh).

Benjamin Franklin invented the bifocals in 1784. On his long trips he liked to read as well as admire the scenery and he didn't like to keep changing his glasses. So, he put one half of each lens in the same frame!

Katherine Blodgett is credited with changing the glasses in America (patent in 1938). With her research on monomolecular coatings, she discovered a way to apply the coatings layer by layer to glass and metal. The thin films, which naturally reduced glare on reflective surfaces, when layered to a certain thickness, would completely cancel out the reflection from the surface underneath. This resulted in the world's first 100% transparent or "invisible" glass. This technology was incorporated into cameras, telescopes, and other inventions. She earned a Master's in physics at the age of 19 from Bryn Mawr, was the first female to earn a Ph.D. in physics at Cambridge in 1926 and the first female hired by GE Research Lab.

Leonardo da Vinci came up with the idea for contact lenses in 1508. Glassblower F.E. Muller of Germany produced ones made of glass in 1887, but they were so painful they could only be worn for one hour. William Feinbloom of New York created the first American made rigid plastic lenses in 1938 and finally the flexible soft lense came about in the 1970's.

Reference: Kids Discover Magazine, "Eyes". Feb. 2000.

(Photo Captions)

Fig. 1 Anatomy of the eye.
(Permission to use by National Eye Institute, National Institutes of Health)

Fig. 2 Anatomy of an actual sheep's eye.

Fig. 3 Student's thank you note to instructor.

Fig. 4 Instructors assisting students during the sheep eye dissection.

page one       page two

You may download a PDF format of the actual newsletter.

 
 
 

BioFocus
Biofocus is published by the Michigan Society for Medical Research. Please send your questions, comments, and suggestions to:

MISMR
P.O. Box 3237
Ann Arbor, MI 48106-3237
Voice: (734) 763-8029
Fax: (734) 930-1568
Email: MISMR@umich.edu

MISMR members strongly support humane animal study in research. We hope that likeminded citizens will join us in working for rational public policy that assures the continued appropriate use of animals in the course of good science.