Question 1

Which of the following best describes the difference between descriptive and inferential statistics in biology?

Accepted Answer

Descriptive statistics summarize or describe observations, while inferential statistics use observations to make estimates or predictions about a population.

Question 2

A researcher collects the following data on the number of hours students study per week: 2, 4, 4, 6, 8. What is the median of this data set?

Accepted Answer

$$4$$

Question 3

Which measure of central tendency is most appropriate for a data set with extreme outliers, and why?

Accepted Answer

The median, because it is not distorted by extremely large or small values.

Question 4

Given the following data set: 10, 55, 85, 25, 44, 37, 42, 201, 56, 59, what is the range?

Accepted Answer

$$201 - 10 = 191$$

Question 5

Which formula correctly represents the calculation for standard deviation ($$s) in a $$sample?

Accepted Answer

$$s = \sqrt{\frac{\sum (x_i - \overline{x})^2$}{n-1}}$$

Question 6

If a sample has a high standard deviation, what can you infer about the data?

Accepted Answer

There is a large amount of variability, and factors other than the independent variable may be affecting the results.

Question 7

In a normal distribution, approximately what percentage of observations fall within two standard deviations of the mean?

Accepted Answer

$$95\%$$

Question 8

A biology class measures the heights of five tomato plants: 65 mm, 52 mm, 71 mm, 56 mm, and 61 mm. What is the mean height?

Accepted Answer

$$61$$\ mm

Question 9

Which of the following would decrease the standard error of the mean ($$SE_{\overline{x}}) $$for a sample?

Accepted Answer

Increasing the sample size.

Question 10

Given the formula for standard error of the mean: $$SE_{\overline{x}} = \frac{s}{\sqrt{n}}$$, what happens to $$SE_{\overline{x}} if$$ $$n$$ increases while $$s$$ remains constant?

Accepted Answer

$$SE_{\overline{x}}$$ decreases.

Question 11

A bar graph shows two groups with overlapping error bars representing $$\pm 2 SE_{\overline{x}}. $$What does this indicate about the difference between the means?

Accepted Answer

The difference is likely due to chance and not statistically significant.

Question 12

Which statistical test would you use to compare observed and expected frequencies in categorical data?

Accepted Answer

Chi-square test

Question 13

A researcher finds that the mean watch time for TikTok in a sample of 100 students is 50 min, with a standard deviation of 35. What is the standard error of the mean ($$SE_{\overline{x}}$$)?

Accepted Answer

$$SE_{\overline{x}} = \frac{35}{\sqrt{100}} = 3.5$$

Question 14

Which of the following statements is a prediction rather than a summary or generalization?

Accepted Answer

"The earlier you start reviewing, the better you are likely to do on the Bio exam."

Question 15

If the standard deviation of a data set is zero, what does this indicate about the data?

Accepted Answer

All data points are equal to the mean.

Question 16

A scientist wants to know if the difference in plant height between two treatments is significant. The error bars for the two groups do not overlap. What can the scientist conclude?

Accepted Answer

The difference is likely statistically significant.

Question 17

Which of the following is NOT a measure of central tendency?

Accepted Answer

Standard deviation

Question 18

A data set has a mean of 20 and a standard deviation of 5. What is the range that includes approximately 95% of the data in a normal distribution?

Accepted Answer

$$20 \pm 10 ($$from 10 to 30)

Question 19

Which of the following best explains why the median is often used instead of the mean for income data in a population?

Accepted Answer

The median is not affected by extreme values, while the mean can be skewed by very high or low incomes.

Introduction to Statistics in General Biology

Study Guide - Practice Questions

Study Guide - Flashcards