Unit 7, Review

What are the two main processes that natural selection promotes for organisms with favorable traits?

To survive and reproduce.

Why is evolution considered a theory?

It explains how organisms change over time, is based on data, and has been scientifically tested.

What is evolutionary fitness measured by?

Reproductive success.

How does natural selection differ from artificial selection?

Natural selection occurs without human interference, while artificial selection involves humans selecting desirable traits.

What can contribute to phenotypic variation in a population?

A population's genotype and different environmental factors.

What are non-selective pressures?

Factors that change the gene pool of a population unpredictably.

What is the bottleneck effect?

A significant reduction in population size that leads to decreased genetic diversity.

What does it mean if a trait is 'highly conserved'?

It has been maintained by natural selection and remains relatively unchanged over time.

What is the main difference between genotype frequencies and phenotype frequencies in a population?

Genotype frequencies represent allele occurrence, while phenotype frequencies represent observable traits.

What is the principle of parsimony in phylogenetics?

To use the fewest assumptions to connect species.

What does adaptive radiation lead to?

Diversification of organisms and formation of new species.

How can ecological stress affect extinction rates?

Ecological stress can quicken extinction rates.

What evidence supports the endosymbiotic theory?

Mitochondria and chloroplasts have circular DNA, double membranes, can function independently, and contain ribosomes.

What is descriptive statistics?

Descriptive statistics summarize and organize data to provide a clear overview.

How does descriptive statistics differ from inferential statistics?

Descriptive statistics describe the data set, while inferential statistics make predictions based on that data.

What are measures of central tendency in descriptive statistics?

Mean, median, and mode.

What is the mean?

The average of a set of values, calculated by dividing the sum of all values by the number of values.

What is the median?

The middle value in a data set when arranged in ascending order.

What is the mode?

The value that appears most frequently in a data set.

What are measures of variability?

Statistics that describe the spread of data points, including range, variance, and standard deviation.

What is range in descriptive statistics?

The difference between the highest and lowest values in a data set.

What is variance?

A measure of how far each number in the set is from the mean, indicating the data set's dispersion.

What is standard deviation?

The square root of variance, representing the average distance of each data point from the mean.

What is a frequency distribution?

A summary of how often each value occurs in a data set.

What is a histogram?

A graphical representation of frequency distribution using bars.

What is a box plot?

A visual representation that highlights the median, quartiles, and potential outliers in a data set.

What are quartiles?

Values that divide a data set into four equal parts, indicating the distribution of values.

What are outliers?

Data points that differ significantly from other observations, potentially impacting the analysis.

What is a normal distribution?

A symmetric, bell-shaped distribution where most values cluster around the mean.

What is skewness in a data set?

The measure of asymmetry in the distribution of values, indicating whether data points lean towards one side.