SME
Grade 9 Science · Problem type
Bacteria growing in a flask
Use this for “Why does the number of bacteria level off and then fall?”
Put in order
Put the growth phases in order.
1
?
2
?
3
?
4
?
Assumptions
•
A flask holds a fixed amount of food and never has its wastes removed.
•
Growth is fastest in the exponential phase; it stops when births equal deaths.
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