Question 1
Five nutrient-agar Petri dishes are labelled 1 Control (not opened), 2 Inside of mouth, 3 Unwashed fingertip, 4 Clean fingertip and 5 A chosen surface. Observe through the closed lids; do not reopen growing cultures. Your teacher handles safe disposal.
Observe the Petri dishes every second day without a microscope. On your own, record your observations in the table below, using written notes or drawings. After a week, observe each dish with a hand lens. What do you see?
Record each of the five dishes on Day 3, Day 5 and Day 7.
| Petri dish | Day 3 | Day 5 | Day 7 |
|---|---|---|---|
| 1 Control | | | |
| 2 Inside of mouth | | | |
| 3 Unwashed fingertip | | | |
| 4 Clean fingertip | | | |
| 5 Chosen surface: ___ | | | |
Observe the Petri dishes every second day without a microscope. On your own, record your observations in the table below, using written notes or drawings. After a week, observe each dish with a hand lens. What do you see?
Record each of the five dishes on Day 3, Day 5 and Day 7.
| Petri dish | Day 3 | Day 5 | Day 7 |
|---|---|---|---|
| 1 Control | | | |
| 2 Inside of mouth | | | |
| 3 Unwashed fingertip | | | |
| 4 Clean fingertip | | | |
| 5 Chosen surface: ___ | | | |
