Does Caffeine Affect Heart Rate?

APPARATUS

• culture of daphnia
• three cavity slides
• three dropping pipettes
• distilled water
• caffeine solution
• cotton wool
• pipettes
• test tubes
• stop clock
• paper towels
• microscope

METHOD

Put a few pieces of paper towel on the cavity slide; this will help to restrict the movement of the daphnia. Using a pipette, transfer one large daphnia to the cavity…