The Cell Chapter 7

Introduction n Robert Hooke, 1665 observed cork with a microscope and saw tiny boxes - called them cells n Leeuwenhoek observed pond water and saw tiny animals made of one cell

Introduction Continued n Schleiden discovered plants are made of cells n Schwann discovered animals are made of cells n Virchow discovered that cells come from other living cells

CELL THEORY 1. All organisms are composed of one or more cells. 2. The cell is the basic unit of organization. 3. All cells come from preexisting cells.

Two Cell Types n Prokaryotic Lacks organelles - internal membrane bound structures single-celled organisms (Bacteria) n Eukaryotic Contains internal membrane-bound organelles Can be single-celled or multi-celled organisms l Two main types: plant and animal

Use the information in the following slides to complete the Eukaryotic Cell Parts chart on pages 45 and 46 of the biology resource manual. The ANALOGY section will be left blank.

Plasma Membrane All cells Regulates what enters and leaves the cell Provides protection and support

Cell Wall Plant cells only Protects and supports the cell

Nucleus Animal and Plant cells only Contains all the cell’s DNA Surrounded by a nuclear envelope

Nucleolus Plant and Animal cells only Assembles ribosomes

Cytoplasm All cells Portion of the cell outside the nucleus “Fluid” inside the plasma membrane

Endoplasmic Reticulum Plant and Animal cells only Assembles lipids, proteins, and other materials in the cell

Ribosomes All cells Site where proteins are assembled

Golgi Apparatus Plant and Animal cells only Modifies, sorts, and packages proteins and other materials for storage in the cell or transport out of the cell

Vacuole Plant and Animal cells only, often very large in plant cells Stores water, food, waste, and other materials

Lysosomes Plant and Animal cells only Contain enzymes to break down molecules and recycle cell parts

Mitochondria Plant and Animal cells only Converts chemical energy stored in food into energy the cell can use

Chloroplasts Plant cells only Converts energy of the sun into chemical energy (site of photosynthesis)

Cell Locomotion Flagella – Long projections that move with a whiplike motion Cilia – Short hairlike projections that beat in a coordinated wave