What is the difference between an autotroph and a heterotroph, and how is this distinction used in a dichotomous key?

Autotrophs make their own food (e.g., through photosynthesis), while heterotrophs obtain food from external sources. This difference helps classify organisms based on their feeding habits.

The video mentioned that a specimen's size was measured in micrometers. What does this indicate about the organism?

It indicates that the organism is microscopic and requires a microscope to be seen clearly.

Classifying Life

9th Grade•45 minutes

Learning Objective

I can classify organisms into the correct groups based on their characteristics.

Key Concepts

A dichotomous key is a tool used to identify organisms based on a series of statements that are typically organized in pairs.

Scientific names often have Latin or Greek roots and can be used across different languages, while common names vary by language and location.

When using a dichotomous key, always start with #1 and go through the sequence of steps carefully.

Practice Questions

This lesson includes 9 practice questions to reinforce learning.

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1. What is the primary purpose of using a dichotomous key in biology?

2. Why are scientific names, often derived from Latin or Greek, important in the scientific community?

3. According to the video, what is the first step you should always take when using a dichotomous key to identify an organism?

...and 6 more questions

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Dichotomous Keys: Identification Achievement Unlocked

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