The CellChapter 7

Introduction Robert Hooke, 1665

• observed cork with a microscope and saw tiny boxes - called them cells

Leeuwenhoek• observed pond water and saw tiny

animals made of one cell

Introduction Continued Schleiden

• discovered plants are made of cells

Schwann • discovered animals are made of cells

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 Prokaryotic

• Lacks organelles - internal membrane bound structures

• single-celled organisms (Bacteria)

Eukaryotic• Contains internal membrane-bound

organelles• Can be single-celled or multi-celled

organisms 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