How to Disect fish Flashcards
What are the ethical concerns?
People worry about how the animals for dissections are raised and killed
It goes against the religious beliefs of some individuals
Apparatus
Scissors
Scalpel
Tweezers / Forceps
Dissection board
Paper towels
Biological specimen
Pins
Method
A lab coat, gloves and eye protection should be worn
To avoid contamination with biological material (which could cause an allergic reaction)
Place the specimen on the dissecting board
Use the tools to access the desired structure
When using the scalpel cut away from your body and keep your fingers far from the blade to reduce the chance of cutting yourself
Scissors can be used for cutting large sections of tissue (cuts do not need to be precise)
A scalpel enable finer, more precise cutting and needs to be sharp to ensure this
Use pins to move the other sections of the specimen aside to leave the desired structure exposed
Limitations
It can be hard to see some of the smaller, finer structures within organs
The specimens do not reflect how the tissue would look in a living organism
If only a single specimen is dissected then anomalies found within that specimen may be ignored or glossed over
Dissection of gas exchange surfaces
The main structures of the gas exchange systems in mammals and fish can be revealed in dissections
The much smaller gas exchange systems of organisms such as insects can be more difficult to examine by dissection
Mammalian lungs
The key structures that can be seen from a dissection of mammalian lungs are shown in the image below
Trachea
Bronchi
Bronchioles
Bony fish gills
The key structures that can be seen from a dissection of fish gills are shown in the image below
Gill arch
Filaments
Insect tracheal system
Due to the small size of insect tracheal systems specialised equipment and skills are sometimes required to dissect them
Microscopes are also needed to observe the structures
