By: Dave Gervais – 01-2-2020
Curriculum Connection:
Grade 10 Tissues, Organs and Systems of Living Things
Gr 11 Biology: Genetics (oogenesis, meiosis)
Getting the sample: Chicken farmers generally slaughter their animals in the fall. A list of provincially licensed meat plants can be found on the Ministry of Ontario Agriculture, Food and Rural Affairs website. Most will provide teachers with sample organs from a wide variety of organ systems. STAO’s resource Safe ON Science states that as fresh animals are raised for human consumption, it is safe to study their organs. Precautions include using the organs as soon as possible, using gloves and wiping all surfaces that the organs came in contact with, with a disinfectant. Our safety resource Safe ON Science is available from the STAO store.
Preparing the sample: In chickens, the ovaries are attached along the backbone, and located about 6cm from the anus. They appear as a mass of developing eggs ranging in size from microscopic to eggs that are several millimeters in diameter. A small sample of the tissue can easily be removed with sharp scissors, and then a temporary slide can be made by applying pressure to a plastic coverslip. The tissue can be smeared across with the coverslip, making parts of the tissue translucent.
Recording the observation: A cell phone camera was used, by simply holding the cell phone to the eye piece. With practice, several pictures were taken. These were reviewed and the best images were kept.
This was taken using the low power objective. The pointer shows a large ovum.
Please note that due to the corona virus outbreak the 2020 STAO conference has been CANCELLED
Dave Gervais
Chair STAO Safety Committee