Required Practical 5

Question 1

Describe precautions that should be followed when performing a dissection.

Answer 1

1. Cover any cuts with a waterproof dressing.
2. When using a scalpel, cut away from body onto a hard surface.
3. When using a scalpel, use a sharp blade.
4. When using a scalpel, carry with blade protected/pointing down.
5. Wear disposable gloves and disinfect hands/wash with soap.
6. Disinfect surfaces/equipment.
7. Safe disposal.
   
   • Put gloves/paper towels/organ in separate bag/bin to dispose.
8. If poisonous chemicals/toxins involved, work in a well ventilated environment.

Question 2

Suggest an ethical consideration when dissecting animals.

Answer 2

• Morally wrong to kill animals just for dissection.
• So use animals for dissection that have already been killed for meat.

Question 3

Describe how you could prepare a temporary mount of a piece of plant tissue for observation with an optical microscope.

Answer 3

1. Add a drop of water to glass slide.
2. Obtain a thin section of specimen and place on slide.
3. Stain.
4. Lower coverslip at angle using mounted needle without trapping air bubble.

Question 4

What are the rules of scientific drawing?

Answer 4

• Look similar to specimen/image, draw all parts to same scale/relative size.
• No sketching - only clear, continuous lines.
• No shading / hatching.
• Include a magnification scale.
• Label with straight,uncrossed lines.