Look at the pictures below. There are a variety of specialized cells that exist in organisms.
Nucleus, Cytoplasm, Membrane What constitutes a cell? More than any other structures, it's the nucleus, cytoplasm, and membrane. Explore the form and function of these three critical cell parts in this video segment adapted from Carolina Biological Supply's An Introduction to the Living Cell.
Discuss the following questions with your partner and write down the answer in your notebook (labs and notes section).
1. How does the structure of a cell suggest its function?
2. In what way does the nucleus dictate the structure and function of the cell?
3. How does the cell membrane act as the "gatekeeper" for the cell?
eThere may be a dozen different types of materials passing through the membrane of a cell at any one time. The job of the membrane is to regulate this movement in order to maintain the proper balance of ions, water, oxygen, carbon dioxide, nutrients, and other molecules. The following interactive feature illustrates the movement of some of these materials and describes the structures that make it possible Explore the Cell Membrane: Just Passing through interactive activity.
Discuss the following questions with your partner and answer in your note sections.
4. How does the composition of the cell membrane help regulate the movement of substances into and out of the cell?
5. Describe the different processes involved in the movement of these substances into and out of the cell; oxygen, carbon dioxide, glucose, potassium, sodium, water, and enzymes.
For the longest time, scientists couldn't imagine how simple cells managed to perform so many amazing tasks in living organisms. It turns out that cells aren't simple at all. Much like complex organisms with organs that perform specific tasks, cells have many organelles that keep them functioning properly. Explore some of a cell's most important structures in this video segment from An Introduction to the Living Cell.
6. What is meant by the phrase "the cell is the functional unit of life"?
7. How are the organelles in a cell like the organs in a human body?
8. Why do you think cells that produce large numbers of proteins have more rough endoplasmic reticulum (ER) than cells that produce fewer proteins?
9. In which kinds of human cells would you expect to find the most mitochondria? The most lysosomes? The most ribosomes? Explain your answers.
As you've probably noticed, there are some striking differences between plants and animals, especially vertebrate animals. But how different are your cells from the cells of a plant? Compare the two images provided and see for yourself.
What are the most significant differences between animal and plant cells?
Check out this cell interactive to look at the organelles and their functions a little closer.