The Cell Cells are the basic unit of living things

Leeuwenhoek 1674 First to describe cells as seen through a simple microscope

Robert Hooke In 1665, Robert Hooke viewed cork samples. He observed hollow boxes which he called cells.

In the 1830’s Schleiden and Schwann studied plant and animal cells.

Schleiden All plants are made of cells.

Schwann All animals are made of cells.

Cell Theory 1. All organisms are composed of one or more cells.

Cell Theory 2. The cell is the basic unit of organization for organisms.

Cell Theory 3. All cells come from pre-existing cells.

BASIC CELL TYPES Prokaryote Eukaryote

Prokaryote Primitive cells without organelles. Lacks internal structures surrounded by membranes Lacks a true nucleus DNA is contained in the nucleoid Most are single-celled organisms

Eukaryote Has membrane bound structures Has a true nucleus Allows cells parts to specialize in particular functions Can be unicellular or multicellular Membrane-bound structures are called organelles Allows different chemical reactions to take place

Cell Structures and Functions

Plasma Membrane AKA: cell membrane Location: Surrounds the cell Function: boundary between cell and environment Controls what goes into and out of the cell.

Cell Wall Location: surrounds the plasma membrane in plant cells Function: support

Nucleus Location: center of the cell Function: manage cell functions

Nuclear Envelope Location: surround the nucleus Function: controls what goes into and out of the nucleus

DNA Location: in the nucleus, on the chromosomes Function: produce the codes for protein synthesis

Chromatin Location: in the nucleus, made from DNA Function: form chromosomes during cell reproduction

Nucleolus Location: in the nucleus Function: produce ribosomes

Ribosomes Location: nucleolus, endoplasmic reticulum, cytoplasm Function: assembles enzymes and proteins for protein synthesis

Cytoplasm Location: from the nuclear envelope to the cell membrane, surrounding the organelles Function: a clear, jelly-like fluid that holds the organelles in place

Endoplasmic Reticulum Location: within the cytoplasm Function: site of lipid synthesis and cell’s delivery system

Golgi Apparatus Location: within the cytoplasm Function: Receives and distributes the new proteins from the ER and distributes substances from the vesicles

Vacuole Location: within the cytoplasm One large vacuole in plants Function: temporary storage of material (food, water, waste, enzymes) One large vacuole in plants Many small vacuoles in animals

Lysosomes Location: within the cytoplasm (animals only) Function: digest enzymes, worn out or extra cell parts, food, virus/bacteria

Mitochondria AKA: powerhouse Location: within cytoplasm Function: breaks down food to release energy

Chloroplasts Location: within cytoplasm (plants only) Function: change light energy into usable chemical energy

Chlorophyll: green pigment that gives plants their color and traps light Belongs to a group of plant organelles called plastids; which are used for storage. They store starches (carbs), lipids, and pigments.

Cytoskeleton Location: Within the cytoplasm Function: provides support for organelles

Composed of microtubules and microfilaments microtubules: thin hollow cylinders made of protein microfilaments: solid protein fibers

Cilia Location: outside of the cell, short, hair-like Function: move the cell

Flagella Location: outside the cell, long, whip-like Function: move the cell

Centriole Location: in the cytoplasm (animal cells only) Function: aid in cell division