Mrs. Misty Smith's 6th-grade science classes have been very busy this 9 weeks, focusing on Structure and Function of Life.
Have you ever thought about the characteristics scientists use to classify things as living or nonliving? Well, the first thing you should know is "ALL LIVING THINGS are made of 1 or more CELLS," and those cells are made of organelles or "tiny organs" that help each cell survive.
One of the first things students learned was that all cells have an outer covering called a cell membrane. Students started to explore the function of a cell membrane using a shell-less egg. The shell was removed by first soaking the egg in vinegar, leaving only the membrane around the egg. Then
Students tested the egg in corn syrup and then water to observe the effects of each substance on the "cell". After analyzing their qualitative and quantitative observations, students were able to communicate the membrane's function. Based on the evidence, the structure of a cell membrane is selectively permeable; it has tiny pores or holes that allow objects to move across it, thus controlling what enters and leaves the cell.
After this Egg Osmosis Lab, students continued to study other organelles found within cells. They realized that many organelles are common in both plant and animal cells, but there were a few others that were found only in plant cells. After much practice identifying and communicating the function of these organelles, students participated in yet another exploration lab. Students used microscopes to analyze and identify "Mystery Cells". Students recorded the images observed as micrographia and made qualitative observations about the cell structure. Students focused their attention on identifying organelles such as the cell membrane, nucleus, cell wall, and chloroplast. In doing so, students were able to classify each mystery slide as either a plant or animal cell using only the evidence observed.
