Bio 021

While we have always been made of cells, it took us a long time to see them. What innovation below was critical to the discovery of cells, showing the relationship of science and technology?

• Dissatisfaction with the theory of spontaneous generation.

• Electricity, to power the microscope.

• Glass lenses, to magnify tiny things clearly.

The Cell Theory is based on two observations. That all living things are made of cells and that all cells come from other cells. Which of these observations was made first?

• All living things are made of cells.

• All cells come from other cells.

van Leeuwenhoek called the organisms he viewed in his microscope “little animals” and described parts like legs, fins, and heads. Later studies would show that these organisms have a nucleus. What kind of cells did he likely view?

• Prokaryotic, single-celled organisms

• Prokaryotic, multi-celled organisms

• Eukaryotic, single-celled organisms

• Eukaryotic, multi-celled organisms

Which of the following organelles would you expect to find in a prokaryotic cell?

• Mitochondria

• Ribosome

• Golgi apparatus

• Lysosomes

Which of the following pairs does NOT match an organelle with its function in cells?

• Lysosomes - breaking down materials

• Rough Endoplasmic Reticulum - site of protein synthesis

• Cell Wall - controls movement of materials into and out of the cell

• Chloroplasts - energy harvesting for plants

While both prokaryotes and eukaryotes have DNA, in prokaryotes DNA is arranged in a circle, whereas in eukaryotes DNA is arranged in linear strands.

• True

• False

Because they have the same DNA and come from the same single cell, all of the cells in a human look the same.

• True

• False

Macrophages are cells in the human immune system whose job it is to take in and then break down potentially harmful materials like germs and cancer cells. Which organelle below would you expect to find in abundance in macrophages?

• Chloroplasts

• Ribosomes

• Lysosomes

• Mitochondria

Muscle cells have special fibers that use ATP to slide across each other to allow muscle contraction and, thereby, movement. Which organelle below would you expect to find in abundance in muscle cells.

• Mitochondria

• Lysosomes

• Cell wall

• Plasma membrane

The first formal statement in cell theory was that:

• Every cell has a nucleus.

• All living things are made of cells.