## Do bacteria grow exponentially?

Bacterial growth is proliferation of bacterium into two daughter cells, in a process called binary fission. Hence, bacterial growth occurs. Both daughter cells from the division do not necessarily survive. However, if the number surviving exceeds unity on average, the bacterial population undergoes exponential growth.

**What happens in the exponential phase of bacterial growth?**

Exponential (Log) Phase: After the lag phase, bacterial cells enter the exponential or log phase. This is the time when the cells are dividing by binary fission and doubling in numbers after each generation time.

**How do you speed up bacterial growth in a Petri dish?**

Place the Petri dishes in a warm, dark place.

- The ideal temperature for growing bacteria is between 70 and 98 degrees F (20-37 degrees C).
- Leave the bacteria to develop for 4-6 days, as this will give the cultures enough time to grow.

### Why do bacteria have exponential growth?

Bacterial growth involves more than just a rate constant. To sustain exponential growth, the cell must carefully coordinate the accumulation of mass, constant replication of the chromosome, and physical division. Hence, the growth rate is centrally important in any physical and chemical description of a bacterial cell.

**What is the purpose of a bacterial growth curve?**

bacterial growth curve A curve on a graph that shows the changes in size of a bacterial population over time in a culture. The bacteria are cultured in sterile nutrient medium and incubated at the optimum temperature for growth. Samples are removed at intervals and the number of viable bacteria is counted.

**Can I grow bacteria without agar?**

Plain agar won’t work because it contains no ‘food’ for the bacteria. You have to buy NUTRIENT agar because that has sugars, salts, nitrogen source, etc that bacteria need to grow.

## What bacteria has exponential growth?

The rate of exponential growth of a bacterial culture is expressed as generation time, also the doubling time of the bacterial population….

Bacterium | Medium | Generation Time (minutes) |
---|---|---|

Streptococcus lactis | Lactose broth | 48 |

Staphylococcus aureus | Heart infusion broth | 27-30 |

Lactobacillus acidophilus | Milk | 66-87 |

**Which is the phase of exponential growth in bacteria?**

The exponential or log phase is a time of exponential growth. In the stationary phase, growth reaches a plateau as the number of dying cells equals the number of dividing cells. The death phase is characterized by an exponential decrease in the number of living cells.

**How can you keep bacteria from growing in a petri dish?**

A suggestion: Place a drop (no more) of a hand sanitizing gel in the middle of one of the squiggles. The hypothesis is that the antibacterial chemical in hand sanitizer will keep bacteria from growing there.

### How much agar do you need to make a petri dish?

You’ll need a clean, microwave-safe container (a quart-sized bowl works great) to mix the agar with water and then boil it. These proportions make enough nutrient agar to prepare two Petri dishes. Stir these together well: • ½-teaspoon agar (about 1.2 grams)

**What happens in the log phase of bacterial growth?**

The exponential or log phase is a time of exponential growth. In the stationary phase, growth reaches a plateau as the number of dying cells equals the number of dividing cells. The death phase is characterized by an exponential decrease in the number of living cells. Bacteria require certain conditions for growth,