Introduction to the Cell 4-1 Structure and Function of the Cell

Both living and nonliving things are composed of molecules made from chemical elements. These elements are organized into macromolecules that in turn make up a cell, the smallest unit of matter that can carry on the processes of life.

Every living thing is made of at least one cell

Development of the cell theory. 1665- Robert Hooke used a microscope to examine a thin slice of cork.

Development of the cell theory. 1673- Anton van Leeuwenhoek was the first person to see living cells under a microscope.

3 German Scientists provided the foundation for the cell theory: 1838- Matthias Schleiden: all plants are made of cells 1839- Theodor Schwann: all animals are made of cells 1855- Rudolf Virchow: cells only come from other cells

All living things are composed of one or more cells. The Cell Theory All living things are composed of one or more cells. Cells are the basic unit of structure and function of an organism. Cells only come from the reproduction of existing cells.

Limiting Factor of Cell Size Cells vary in shape, size and internal composition.

Most cells range in size from 10-50 um (micrometers, 10-6 m), and are visible only with a microscope.

Cells are limited in size by the ratio between their outer surface area and inner volume. Resources must enter through the surface of the cell and must be enough to meet the cell’s needs

Cell Structure and Function Cells come in a variety of shapes. With each shape, the form will reflect the function.

Prokaryotes and Eukaryotes Many cells have specialized internal structures called organelles that carry out the life functions. The entire cell is surrounded by a cell membrane.

Prokaryotes and Eukaryotes There are two different types of cells classified according to how their internal environment is organized. Prokaryotes and Eukaryotes

Contain membrane-bound organelles, the larges of which is the nucleus. Eukaryotes Contain membrane-bound organelles, the larges of which is the nucleus. The nucleus contains the genetic information.

These unicellular organisms lack membrane-bound organelles. Prokaryotes These unicellular organisms lack membrane-bound organelles. Prokaryotic cells are capable of carrying out the same functions as a eukaryotic cell but do so in a different way.