Cell Structure and Function
Section 71:
Robert Hooke used an early compound microscope to look at a thin slice of cork. It seemed to make tiny empty chambers (cells).
Anton van Leeuwenhoek used a singlelens microscope to observe pond water & other things. The microscope revealed a world of tiny living organisms that seemed to be everywhere.
Matthias Schleiden concluded that all plants were made up of cells.
Theodor Schwann stated that all animals were made up of cells.
Rudolf Virchow concluded that new cells could be produced only from the division of existing cells.
Janet Plowe demonstrated that the cell membrane is a physical structure, not an interface between two liquids. Lynn Margullis proposed the idea that certain organelles were once free living themselves. Cell Theory:
All living things are composed of cells.
Cells are the basic units of structure and function in living things.
New cells are produced from existing cells. 2 Types of Cells:
Eukaryotes are cells that contain nuclei. They contain a nucleus in which their genetic material is separated from the rest of the cell.
Prokaryotes are cells that do not contain nuclei. They have genetic material that is not contained in a nucleus. Section72:
An organelle is a specialized structure that performs important cellular functions within an eukaryotic cell.
A plant cell has a cell wall and a cell membrane while a animal cell has just a cell membrane.
Organelles:
Nucleus: Contains nearly all the cell’s DNA & with it the coded instructions for making proteins & other important molecules. (Both)
Ribosomes: small particles of RNA & proteins found throughout the cytoplasm. Proteins are assembled on ribosomes. (Both)
Endoplasmic Reticulum: internal membrane system, the site where lipid components of the cell membrane are assembled, along with proteins and other materials that are exported from the cell. (Both)
Golgi