Unicellular and Multicellular Organisms

Which of the following organisms is unicellular?

• bacteria

• daisy

• spider

• earthworm

Which of the following correctly describes a difference between unicellular organisms and multicellular organisms?

• Unicellular organisms perform all of their life processes within a single cell, but multicellular organisms have different kinds of cells that each perform specialized functions.

• Unicellular organisms must make all of the substances they need inside of their cells, but multicellular organisms are able to take in substances from their environment.

• Unicellular organisms have different kinds of cells that perform specialized functions, but multicellular organisms have cells that all perform the same function.

• Unicellular organisms are able to take in substances from their environment, but multicellular organisms must make all of the substances they need inside of their cells.

Anna is observing a sample of pond water with a microscope. She sees the following two organisms in the sample. Anna's teacher tells her that the paramecium is a single-celled organism, whereas the fairy shrimp is a multi-celled organism. Which of the following is a difference between single-celled and multi-celled organisms?

• Single-celled organisms need food to survive, but multi-celled organisms do not.

• Single-celled organisms are more complex than multi-celled organisms.

• Multi-celled organisms need food to survive, but single-celled organisms do not.

• Multi-celled organisms are more complex than single-celled organisms.

Humans, fish, and trees are all living things. What is true for all living things?

• All living things can grow leaves.

• All living things have bones.

• All living things can swim in water.

• All living things are made of cells.

Which of the following animals probably has the most cells?

• fly

• frog

• whale

• cat

All organisms are made up of cells. Organisms can have:

• only one cell each.

• one cell or many cells.

• 200-300 cells each.

• either many cells or no cells.

Single-celled organisms must be able to:

• choose only one function to perform with their one cell.

• perform all necessary functions with only one cell.

• specialize their cells to each perform a specific function.

• perform no functions with any of their cells.

A very complex organism, such as a human, is likely a _______ organism.

• multi-celled

• single-celled

• two-celled

• complex-celled

Which is the best way to classify grasshoppers?

• Grasshoppers are multi-celled organisms because they are made up of one cell that carries out all of their life processes.
• Grasshoppers are single-celled organisms because they are made up of one cell that carries out all of their life processes.
• Grasshoppers are single-celled organisms because they are made up of many cells that carry out all of their life processes.
• Grasshoppers are multi-celled organisms because they are made up of many cells that carry out all of their life processes.

Which best describes a multi-celled organism?

• basic
• simple
• uniform
• complex