CER Practice What are Cells CER Scenario A

C-E-R Practice

What are Cells? CER • Scenario: A unicellular organism is a living thing made of only one cell, while a multicellular organism is a living thing made of more than one cell. • Prompt: Write a scientific explanation that describes the difference in roles between cells in a unicellular organism and a multicellular organism.

Sample Claim A cell within a multicellular organism has to work with other cells to sustain an organism, while a unicellular organism is a cell that relies on itself.

Sample Evidence A unicellular organism is made of one cell. A multicellular organism is made of more than one cell. A unicellular organism relies on itself whereas a multicellular organism relies on each of its cells for survival.

Sample Reasoning All living things are made of cells. Living things have certain characteristics that prove that they live, such a motion, reproduction, and growth. Unicellular organisms are made of one cell which means this organism is independent and can survive without the help of other cells. Unicellular organisms rely on their cell parts to function well so they can survive.

Sample Reasoning, contd. A multicellular is a living things made of more than one cells (multiple cells ). Multicellular organisms have cells that are dependent on each other for survival. Its cells have to work together for survival. If a cell is not working there are enough other cells to compensate for that loss. A malfunctioning cell in a unicellular organism could be fatal.

Misperceptions 1. A living organism is a living organelle that only had one cell, whereas a multicellular organism is a living organelle with multiple cells.

Misperceptions 2. A cell is a multicellular organism because it is made of multiple cells. 3. Unicellular organisms are plants and trees and really simple

Know these words! • • • Unicellular Multicellular Cell Organelle Organism