Chapter 4 - Cell Theory Flashcards
Cell
Smallest structural and functional unit of an organism; usually microscopic; contains cytoplasm and a nucleus enclosed in a membrane
2 main types of cells
Prokaryotic - No Nucleus
Eukaryotic - Has a nucleus
Robert Hooke
Observed the bark of cork trees under a microscope; Thought the objects looked like individual rooms in a monastery, which were called cells; called his discovery cells; did not know their true function
Anton van Leeuwenhoek
Invented the microscope; first person to observe bacteria and protoza (single celled animal); observed and described red blood cells
Mathias Schleiden
Concluded that all plants are made of cells; declared that the cell is the basic building block of all plant matter; sensed the importance of the nucleus of the cell
Theodor Schwann
Concluded that all animals are made of cells; collaborated with Schleiden to form a new theory in biology
cell theory
Schleiden and Schwann became known as CELL THEORY; cells are the basic unit of life
Rudolph Virchow (1855)
Proposed all cells result from the division of previously existing living cells, this became a key piece of the modern cell theory
The modern cell theory states:
- All living things are composed of cells
- All cells come from the division of preexisting cells
- All cells are the basic unit of life
Metabolism
chemical reaction inside the cell
response
perceiving and responding to changes in the envrionment
Homeostasis
keeping the conditions inside the organism within tolerable limits (BALANCED)
Growth
increase in size
Reproduction
producing offspring either sexually or asexually
Nutrition
obtaining food, to provide energy and the materials needed for growth
