bacteria microbe cell nucleus cell membrane protist cytoplasm field of view (optional) magnify/magnification

Review the microscope

Review animal cells

Read the introduction and look for key ideas

What are some of the differences among the cells of two groups of microbes?

Complete the procedure and record your data

Based on your observations, can you conclude for certain which cells do not have a nucleus? Share your thoughts with the class.

Analysis question 1 When you compare the protists, what do you observe?

Analysis question 2 When you observe bacteria, what do you observe?

Analysis question 3 When you compare all of the different microbes, what similarities and differences do you observe?

Analysis question 4 Look at the drawings of micro-life you made for Activity 36, “Looking for Signs of Micro-Life.” Could any of the organisms you saw have been protists or bacteria? Support your answer with evidence from this activity.

Analysis question 5 In your science notebook, create a larger version of the diagram shown below (known as a Venn diagram). Record unique features of cells of each group of organisms in the appropriate space (either “protists,” “bacteria,” or “human” cells). Record common features between groups in the space that overlaps. Hint: Think about what you have learned about cells in the last few activities. Look again at your notes from this activity.

Analysis question 5

SCORING GUIDE: Understanding Concepts

What are some of the differences among the cells of two groups of microbes?

Key vocabulary definitions Bacteria - Single-celled organisms that do not have a nucleus or other membrane-bound organelles. Cell - The smallest structural unit enclosed by a membrane that makes up all living organisms.

Key vocabulary definitions Cell membrane - The structure that separates the cell from its external environment. Cytoplasm - The material that fills much of the inside of cells. Field of view - The area visible through an optical instrument, such as a microscope.

Key vocabulary definitions Magnify/magnification - To enlarge an image of an object, the extent to which an image of an object is enlarged. Microbe - A microscopic cellular organism or a virus.

Key vocabulary definitions Nucleus - A small compartment in the center of the cell which contains the majority of the genetic information and directs the cells’ activities. Protist - An organism made up of a single cell or many cells with a nucleus, and that is not an animal, plant, or fungus.