Specific Biological Concerns

Included in this section:

Animals
Dissection
Plants
Microbes
Body Fluids

Animals

Animal study is an indispensable major portion of any biology curriculum. It facilitates and enhances the study of evolution, ecological relationships, animal behavior, taxonomy, anatomy, physiology, and development. Animal study also gives more meaning to human development and function, as well as engenders in students an awe and a respect for living things.

Any lab involving the use of live animals requires careful planning.

There are basic safety precautions the teacher must be aware of before using animals in the lab:

Animals should be obtained from a reliable biological supply house.
Potential danger exists with wild animals brought in that have been injured or diseased.
Animal weaknesses may be due to an undetected illness.
Animal diseases may include ringworm, rabies or rabbit fever.
Wild animals may carry a variety of vectors (e.g., fleas that carry worms which can be inhaled or swallowed by students; ticks or mites can fall onto the clothing of a student).
Poisonous animals should never be included in first-hand biology studies by high school students.

Experiments involving the sacrifice of animals is not advocated. The study of microorganisms and invertebrates is preferable.

It is important that a qualified adult supervise the handling and humane treatment of animals. Animals are not to be subjected to any discomfort or pain. Hypodermic needle injection is permissible by a qualified person, but surgery on any lab animal or the use of any drug or substance (including alcohol) that can cause adverse effects on the animal is not permitted.

Our professional mandate is stated in a position paper authored by the National Association of Biology Teachers (NABT). The following information is excerpted from the "NABT Guidelines for the Use of Live Animals at the Pre-University Level." It can be found in its entirety in Gerlovich (1985) pp. 150-153.

Living things are the subject of biology and their direct study is an appropriate and necessary part of biology teaching. Textbook instruction alone cannot provide students with a basic understanding of life and life processes. We further recognize the importance of research to understanding life processes and providing information on health, disease, medical care, and agriculture.

The abuse of any living organism for experimentation or any other purpose is intolerable in any segment of society. Because biology deals specifically with living things, professional biology educators must be especially cognizant of their responsibility to prevent inhumane treatment to living organisms in the name of science and research. This responsibility should extend beyond the confines of the teacher's classroom to the rest of the school and the community.

The National Association of Biology Teachers, in speaking to the dilemma of providing a sound biological education at the secondary level, while addressing the problem of humane experimentation, presents the following guidelines on the use of live animals at the pre-university level:

Biological experimentation should lead to and be consistent with respect for life and all living things.
"Humane treatment and care of animals should be an integral part of any lesson which includes living animals."
All aspects of exercises and of experiments dealing with living things must be within the comprehension and capabilities of the students involved.
Lowest orders of life, such as bacteria, fungi, protozoans and insects, can reveal much basic biological information and are preferable subjects for invasive studies wherever and whenever possible.
Vertebrate animals can be used as experimental organisms in the following situations:
- Observations of normal living patterns of wild animals in the free living states or zoological parks, etc.
- Observations of normal living patterns of pets, fish, or domestic animals.
- Observations of biological phenomena (i.e., inducing ovulation in frogs through hormone Injections that do not cause discomfort or adverse effects to the animals).
Animals should be properly cared for:
- Appropriate quarters for the animals being used should be provided in a place free from undue stresses.
- Animal quarters should provide for sanitation, protection from the elements, and have sufficient space for normal behavioral and postural requirements.
- Proper food and clean drinking water for those animals requiring water shall be available at all times in suitable containers.
- No animals should be subjected to overhandling. Instruct students on the proper handling techniques and limit the amount of handling (one hour maximum per day). Students should always wash their hands after handling any animal.
- All animals can bite. Leather gloves should be worn anytime animals are handled.
- If a student is bitten, wash the bite with soap and water and have it checked by a medical specialist. Observe the animal for several days for indications of distress or disease.
- If the animal dies unexpectedly, a veterinarian should examine it to ascertain that a disease communicable to humans was not involved.
- Ill animals should be treated by a licensed veterinarian.
- Animals, like snakes and turtles, can carry salmonella and can transmit this to the students through contact with fecal matter. It is recommended that these animals not be used unless they test negative for salmonella on a routine 3-4 month basis.
All animal studies should be carried out under the direct supervision of a competent science teacher.
Students should not be allowed to take animals home to carry out experimental studies.
There should be no experimental procedures that would subject animals to pain or distinct discomfort.
Experimental procedures should not involve:
- The use of microorganisms pathogenic to animals
- Ionizing radiation, carcinogens, drugs or chemicals at toxic levels
- Drugs known to produce adverse or teratogenic effects
- Pain-causing drugs
- Alcohol in any form
- Electric shock
- Exercise until exhaustion
If euthanasia is necessary, animals shall be sacrificed in an approved, humane manner by an adult experienced in the use of such procedures.
Students should not perform surgery on living vertebrate animals.
Behavioral studies should use only positive reinforcement.
Egg embryos subjected to experimental manipulation must be destroyed humanely at least two days prior to hatching.
Administration of anesthetics should only be carried out by a qualified science teacher.
The following is a partial list of organisms known to cause harmful reactions when handled carelessly (Virkus, 1978):
- Ants, Ioa Caterpillar, Bedbugs, Jelly fish, Bees, Millipede, Black Widow Spider, Mosquitos, Blister Beetle, Mussels*, Brown Recluse Spider, Nettling (Slug) Caterpillar, Chiggers, Oysters*, Clams*, Pussmoth (Saddleback Caterpillar), Copperhead Snake, Potato Beetles, Coral Snake, Rattlesnake, Cottonmouth Snake, Ticks (Dermacenter & Ixodidae), Fleas, Wasps, Gnats, and Yellow Jackets.
  * when living in polluted water or feeding on certain dinoflagellates

Dissection

Preserved animal specimens are used extensively in traditional biology studies to complement the study of anatomy and physiology or evolution. Preserving agents usually consist of 10% solution of formalin (40% solution of formaldehyde gas in water) or dry pack chemicals. There are inherent safety precautions and procedures in the lab when dissecting.

Instruct students in the proper safety procedures.
Teachers and students should be aware of the possible health hazards, such ascuts, reactions to preservatives (faintness/dizziness, allergic responses), and injury from wearing contact lenses.
Avoid contact with preservative chemicals. Pre-soak specimens in water for 24 hours prior to beginning a dissection.
Insure proper room ventilation.
Students should be advised to wear protective aprons or shirts when performing dissections.
Chemical splash safety goggles should be worn.
Wearing rubber or surgical gloves may be recommended especially for students with known skin sensitivities.
Re-acquaint students with the location and use of the eye-wash station or fountain.
Re-emphasize that any chemical splash in the eyes or piercing of the skin by the classroom dissecting equipment, no matter how minor, should be reported to the teacher.
Avoid blunt or dull equipment for making incisions and cuts.
Provide only single-edged blades (scalpels or safety razor blades)for cutting.
Instruct students to:
- Secure specimen in a dissecting pan.
- Cut away from the organism's body.
- Do not make incisions cutting toward one's own body or in the direction of another student.
- Hold probes in the hand opposite the one used for cutting.
- Wash tools and hands in warm, soapy water at the conclusion of each lab period.
Preserved specimens should be stored in a cool place inaccessible to students in sealed, labeled and dated metal or plastic containers. The type of preservative and its concentration should also be labeled on the outside of the container.
All dissected parts should remain in the dissecting tray until they are disposed.
No part of any dissected specimens should ever be ingested or leave the lab room.

Plants

Another major portion of the biology curriculum involves the study of or the use of plants. However, some plants may exhibit a whole range of deleterious characteristics from poisonous oils to thorns. There are 700 species of plants known to cause death or illness. Certain safety precautions also need to be exercised with the use of plants.

Give students specific instructions in using specific kinds of plants.
Students should wash their hands after handling plants. They should also be advised to keep both plants and hands away from direct contact with their faces.
Teachers should be cognizant of any of the following signs of plant poisoning exhibited by any of their students:
- Constriction of pupils of the eye
- Increase in nasal and salivary secretions
- Sweating
- Gastrointestinal disturbance
- Tightness in the chest
- Muscle tremor
- Blueness around the lips and under the fingernails
- Indications of convulsions
If plant poisoning is suspected, first-aid measures may have to be taken and the Poison Control Center alerted.
Parts of the plants in the following lists may threaten the safety of students and teachers. See Gerlovich (1985), pp. 148-149 and Virkus (1978), pp. 84-86 for specific dangers.

House Plants Flower Garden Plants

Hyacinth, Larkspur, Narcissus, Monkshood, Daffodil, Autumn crocus, Oleander, Star of Bethlehem, Diffenbachia, Lily of the Valley, Rosary pea, Iris, Castor bean, Foxglove, Poinsettia, Bleeding heart, Mistletoe, Rhubarb, and Potato

Ornamental Plants, Trees, and Shrubs

Daphne Wild & cultivated cherries, Wisteria Oaks, Golden chain Elderberry, Laurel Black locust, Rhododendron Buckeye, Azalea Yew, Jessamine Hemlock, and Red sage Holly

Wooded or Field Plants Swamp or Moist Area Plants

Jack-in-the-pulpit Water hemlock, Moonseed Nightshade, May apple Jimson weed, Dutchman's breeches, Buttercup, Death camas, and Poison hemlock

If collections are desired, the teacher should review safety precautions specific to local collecting areas and the dangers that may exist.

Wild mushrooms should never be ingested. It is best not to touch any part of an unknown plant.

Microbes

Instruct students in the proper use of a microscope. Safety factors include:
- Carry the microscope with one hand on the arm and the other hand under the base.
- Never focus in direct sunlight.
- Always lower the lens as you watch from the side. Only raise the lens to focus when your eye is over the eyepiece.
Never use pathogenic organisms.
Take into account the impact that concentrated cultures of relatively innocuous bacteria and viruses could have when inexperienced students are working with them.
If cultures are to be passed around, seal the Petri dishes closed with clear tape.
Inoculating loops used for transferring bacteria cultures should be flamed before and after each transfer.
Inoculating loops must be used with care:
- The film held by a loop may break and go into the air.
- A hot loop may cause a spattering of liquid when it is inserted into it.
- When a contaminated loop is inserted into a flame, it may "aerosol" before all the pathogenic organisms are killed by the flame.
Avoid the inhalation of air containing high amount of bacterial or fungal spores. Do not sniff cultures.
Use Lysol (3 pints water:1 pt Lysol concentrate) or Clorox (1 pt Clorox:10 pts water) as a disinfectant.
Always dispose of microorganism cultures by first sterilizing at 15 psi for 15 minutes before disposal.

Body Fluids

The use of human body fluids, such as blood, saliva, urine or body cells in a science classroom, is discouraged. If labs such as these are undertaken, make sure extraction instruments are used only once and that a safe, secure method of disposal of these instruments is implemented.

Blood

Blood typing/microscopic examination of fresh blood is not permitted.

Products that simulate the ABO and Rh antigen-antibody reaction are available from science supply companies.

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