Binary Fission (AQA GCSE Biology)

Flashcards covering binary fission, bacterial reproduction, and growth calculations for AQA GCSE Biology.

What type of organisms reproduce using binary fission?

Prokaryotes (e.g. bacteria).

Is binary fission sexual or asexual reproduction?

Asexual.

What is the outcome of binary fission?

Two genetically identical daughter cells (clones).

Step 1 of binary fission?

Circular DNA and plasmids replicate.

Step 2 of binary fission?

Cell grows and DNA copies move to opposite ends.

Step 3 of binary fission?

Cytoplasm divides and a new cell wall/membrane forms.

Step 4 of binary fission?

Two daughter cells are produced.

What is the formula for bacterial growth?

N = N₀ × 2ⁿ

In the formula N = N₀ × 2ⁿ, what does n represent?

Number of divisions (time ÷ mean division time).

A bacterium has a mean division time of 20 minutes. How many divisions in 2 hours?

120 ÷ 20 = 6 divisions.

Why express large bacterial numbers in standard form?

Required at Higher tier GCSE when answers are very large.

How often can some bacteria divide under ideal conditions?

As often as every 20 minutes.

What factors affect the rate of binary fission?

Nutrient availability, temperature, oxygen, pH, and waste build-up.

Why is binary fission important in culturing microorganisms?

It explains how bacterial colonies grow rapidly and why conditions must be controlled.