All living things are made of cells, from the simplest and smallest unicellular organisms to great blue whales. Cells come in a wide variety of shapes and sizes (morphologies), and serve many different functions. Nerve cells transmit electrical impulses, cells of the pancreas produce the enzymes lipase and insulin, cells in the eyes produce tears, stomach cells are resistant to strong acids, cells in the testes produce sperm. All cells do have certain things in common, including many organelles and structural features.

Sacs of fluid surrounded by membranes. Inside the fluid float chemical and CELL ORGANELLES- structures found inside the cell that are used during metabolic processes

Can also be referred to as the “UPS” system of the cell.

Function: Place where substances that are produced in the cell (such as hormones and enzymes) are packaged up to be shipped to other organelles or to the outside of the cell.

Structure: A flattened stack of five or six membranes (looks like a stack of dinner plates)

Named after the Italian scientist Camillo Golgi

Site of Cell Respiration:

C6H12O6 + 6 O2 6 CO2 + 6 H2O + ATP

“Powerhouse of the cell”

Where energy (ATP) is produced in the cell

Structure: Double membrane,outer layer surrounds the organelle, the inner layer has folds called CRISTAE that increase the surface area. Number varies depending upon type of cell.

During the 1980s, Lynn Margulis proposed the theory of endosymbiosis to explain the origin of mitochondria and chloroplasts from permanent resident prokaryotes. According to this idea, a larger prokaryote (or perhaps early eukaryote) engulfed or surrounded a smaller prokaryote some 1.5 billion to 700 million years ago.

The basic events of endosymbiosis

“Protein Factory” of the cell

Function: Where the amino acids are joined together to make proteins.

Smallest of all the organelles

Some are free within the cytoplasm, others are attached to Endoplasmic Reticulum

Composed of RNA and proteins

Number varies depending upon the type of cell

The “garbage disposal” or “suicide sacs” of the cell

Function: Special vesicles formed by the Golgi Apparatus to clean-up the cell. Remove dead organelles by surrounding them, breaking them down and releasing the proteins which are then used to make new organelles

Structure: Membrane bound sacs containing digestive enzymes. Only found in animal cells.

The “Highway system” of the cell

Function: Transport materials (proteins) around the cell-from organelle to organelle, or from organelle to cell membrane. Also helps to synthesize proteins, carbohydrates and lipids

Structure: A series of canals that connects the nucleus to the cytoplasm of the cell. Has two different forms:

•Rough Endoplasmic Reticulum- Has ribosomes attached

•Smooth Endoplasmic Reticulum- No ribosomes

“Information Center”

Every cell of every living thing has a nucleus, and every nucleus in every living thing contains genetic material.

The genetic material directs the production of proteins that make the entire organism function, the nucleus makes the entire cell function.

NUCLEOLUS:produces RNA which makes ribosomes

Function: Storage area for the cell, stores water, salts, pigments, organic compounds, and some toxic wastes

Structure: Membrane bound sacs, the vacuole is usually the largest organelle in the plant cell, often comprising 80% of a mature cell. Animal cells have smaller, but more numerous vacuoles.

“Storage Tank”

Function: Protects the plant cell, maintains its shape and prevents excessive uptake of water

Structure: Thicker than the cell membrane, exact composition varies from species to species, all made up of

the polysaccaride cellulose embedded in a matrix of other polysaccarides and proteins

Structure: Like mitochondria, plastids are surrounded by two membranes. Only in plant cells Function: Some store starch or fat, many others store pigments that give fruits, flowers and leaves their color.

“Food Factory for the plant cell”

Function: Site of photosynthesis:

6CO2 + 6H2O chlorophyll C6H12O6 + 6O2

light

Structure: Type of plastid.

Chlorophyll are arranged in flattened

sacs-thylakoids, the sacs are stacked together to form

grana

Aid in cell division (mitosis), only found in animal cells

Structure: Two centrioles in each animal cell, each centriole is composed of nine microtubules arranged in a ring.

“Skeletal framework”

In the early days of electron microscopy, biologists thought that organelles floated in a liquid cytoplasm, improvements in microscopy revealed cytoskeleton- a network of fibers extending throughout the cytoplasm.

Function: To provide support and protection, provides anchorage for many organelles.More dynamic than an animal skeleton, it can be quickly dismantled in one part of the cell and reassembled in a new location, thus changing the shape of the cell.

Made up of microtubules (thick) and microfilaments (thin)

Function: Locomotive appendages that protrude from some cells

Found in many unicellular organisms, also in the sperm cells of animals and line the respiratory system of many animals

Cilia: Usually occur in large numbers, shorter than flagella 2 to 20 micrometers.Flagella-Only one or two per cell, longer than cilia, 10 to 200 micrometers

Structure: Specially arranged microtubules