Presentation on theme: "Ch. 4 Section 1 Objectives Name the scientists who first observed living and nonliving cells. Summarize the research that led to the development of the."— Presentation transcript:
1Ch. 4 Section 1 ObjectivesName the scientists who first observed living and nonliving cells.Summarize the research that led to the development of the cell theory.State the three principles of the cell theory.Explain why the cell is considered to be the basic unit of life.
2Section 1 The History of Cell Biology The Discovery of CellsSection 1 The History of Cell BiologyAll living things are made up of one or more cells.A cell is the smallest unit that can carry on all of the processes of life.
3Ch. 4 Cell Discovery cont. Hooke Leeuwenhoek Robert Hooke discovered cells in slices of cork.LeeuwenhoekAnton van Leeuwenhoek was the first to observe living cells in microorganisms.
4Cell Theory Development (Schleiden, Schwann, and Virchow) 1838 Matt Schleiden: All Plants are composed of cells1839 Theodor Schwann: All Animals are composed of cells1847 Rudolf Virchow: Cells come only from other cells
5Cell TheoryThe cell theory states that all living organisms are made of one or more cells, cells are the basic units of structure and function, and cells come only from pre-existing cells.
6Cell Theory cont. Cellular Basis of Life All living things are made of organized parts, obtain energy from their surroundings, perform chemical reactions, change with time, respond to their environment, and reproduce.
7The Cell Theory #1 All living things are made of 1 or more cells #2 Cells are the basic units of structure and function of an organism#3 Cells come only from the reproduction of existing cells (new cells come only from other cells)
8Section 2 Introduction to Cells Objectives:Explain the relationship between cell shape and cell function.Identify the factor that limits cell size.Describe the three basic parts of a cell.Compare prokaryotic cells and eukaryotic cells.Analyze the relationship among cells, tissues, organs, organ systems, and organisms.
9Cell DiversityCell ShapeA cell’s shape reflects its function.
10Cell Diversity cont. Cell Size Cell size is limited by a cell’s surface area–to-volume ratio.
11Surface Area per Volume Ratio 4 sides:1 box4/1=4 sides per square12 sides:9 boxes12/9=1.333 sides per square
13Cell PartsThe three basic parts of a cell are the plasma membrane, the cytoplasm, and the nucleus.
14Cell Parts cont. Plasma Membrane The cell’s outer boundary, called the plasma membrane (or the cell membrane), covers a cell’s surface and acts as a barrier between the inside and the outside of a cell.
15Cell Parts cont. Cytoplasm The region of the cell that is within the plasma membrane and that includes the fluid, the cytoskeleton, and all of the organelles except the nucleus is called the cytoplasm.
16Cell Parts cont. Nucleus The nucleus is a membrane-bound organelle that contains a cell’s DNA.
172 Basic Types of Cells Prokaryotes Prokaryote cells lack a nucleus and membrane-bound organelles.
182 Types of Cells cont. Eukaryotes Eukaryote cells have a nucleus and membrane-bound organelles.