How is a cricket's chirp related to temperature?

The experiment measures how temperature affects cricket chirping.

A suitable aim for the investigation is to determine the effect of temperature on the rate of cricket chirping.
$\boxed{\text{To investigate how temperature affects the number of chirps per minute of a cricket.}}$

2.3.2

These are factors kept constant to ensure a fair test.

Two factors that Esethu and Christine need to control are:

• The species, age, and size of the crickets used.
• The light conditions (e.g., keeping it dark) during the experiment. $\boxed{\text{Species/age/size of crickets, Light conditions}}$

2.3.3

I cannot draw a graph directly in this format, but I can describe how it should be constructed:

• X-axis (horizontal): Label "Temperature (°C)" and scale it appropriately from 10 to 25.
• Y-axis (vertical): Label "Chirps per minute" and scale it appropriately from 0 to 140.
• Plot points: Plot the data points from the table: (10, 40), (15, 75), (20, 105), and (25, 140).
• Draw lines: Connect the plotted points with straight lines to form a line graph.
• Title: A suitable title would be "Effect of Temperature on Cricket Chirping Rate". The graph would show a positive correlation, indicating that as temperature increases, the number of chirps per minute also increases.

2.3.4

Esethu and Christine could improve the reliability of their investigation by repeating the experiment multiple times at each temperature and calculating the average number of chirps.
$\boxed{\text{Repeat the experiment multiple times and average the results.}}$

2.3.5

The table shows that higher temperatures lead to more chirps.

You would expect to hear more cricket chirping in summer.
Reason: Crickets are cold-blooded (ectothermic), meaning their body temperature and metabolic rate are influenced by the surrounding temperature. In summer, the higher temperatures increase their metabolic rate, leading to more frequent muscle contractions and thus more chirping.
$\boxed{\text{Season: Summer. Reason: Higher temperatures in summer increase the cricket's metabolic rate, leading to more chirping.}}$

2.3.6

The term used for animals that are active at night is nocturnal.
$\boxed{\text{Nocturnal}}$