Cell Structure & Function http://koning.ecsu.ctstateu.edu/cell/cell.html

THE CELL THEORY The cell is the basic unit of all living things. All organisms are composed of one or more cells All cells come from pre-existing cells

The History Many people experimented with making microscopes The first microscope was 6 feet long!!! The Greeks & Romans used “lenses” to magnify objects over 1000 years ago.

The History Hans and Zacharias Janssen of Holland in the 1590’s created the “first” compound microscope Zacharias Jansen 1588-1631 The “First” Microscope

The History Robert Hooke & Anton van Leeuwenhoek made improvements by working on the lenses Robert Hooke 1635-1703 Hooke Microscope Anton van Leeuwenhoek 1632-1723

History In 1665 Robert Hooke examined a thin slice of cork with a single magnifying lens and observed tiny compartments He gave them the latin name cellulae, meaning small rooms - hence the origin of the term cell. He later observed cells in plant tissues and observed the cells were “fill’d with juices”

History 1820 - Robert Brown observed a nucleus in orchid cells In the early 1700’s Leeuwenhoek looked at pond water and called the microscopic organisms “animalcules” These were the first observations of living cells 1820 - Robert Brown observed a nucleus in orchid cells

History In 1838, Matthius Schleiden stated all plants are made of cells Theodor Schwann stated all animals are made of cells .

Cell discovery Robert Hooke - discovered cells while looking at cork cells. mid-1600s Anton von Leeuwenhoek - discovered life while looking at pond water. mid-1600s Mattias Schwann - all animals consists of cells.1830s Theodore Schleiden - all plants consists of cells.1830s

What must you do to live? What must cells do to live? What parts are necessary? What functions are necessary? What happens when something goes wrong?

Cells have many different parts called organelles that work together to keep it alive. 3 main parts of the cell: 1. Nucleus – The brain. The nucleus is the control center of the cell. It is the largest organelle in the cell and it contains the nucleolus and DNA. 2. Cell membrane – Gives the cell shape and hold the cytoplasm. 3. Cytoplasm – Jellylike material that makes up most of the cell. Most chemical reaction in the cell take place here. All organelles are suspended in the cytoplasm.

Three main parts of a cell CYTOPLASM CELL MEMBRANE NUCLEUS

The Nucleus!!!! Nuclear membrane (or Nuclear Envelope)– surrounds the nucleus and separates it from the rest of the cell. allows materials in & out of the nucleus.

The Nucleus!!! Has small openings in the nuclear membrane called Pores…. Nuclear Pores allow RNA And other things to enter and Leave

The Nucleus. Nucleolus – 1. found within the nucleus. 2 The Nucleus!!! Nucleolus – 1. found within the nucleus. 2. produces ribosomes.

( in the nucleus) Chromosomes – Carries information that determines what traits a living thing will have. Found within the nucleus. DNA (Deoxyribonucleic Acid) contains all the information for cells to live, perform their functions and reproduce.

Are you still awake? In what direction do the arrows point?

Cell membrane The fluid mosaic model describes the structure of the plasma membrane. Fluid = flexibility. Mosaic = many parts. The membrane is seen as a bilayer of phospholipids in which protein molecules are embedded.

Ribosomes Found in the cytoplasm, but most are attached to the endoplasmic reticulum. Ribosomes produce proteins.

Ribosomes While attached to the ER, ribosomes produce proteins that are needed in the cell and exported elsewhere in the body.

Endoplasmic reticulum – A network of membranes throughout the cytoplasm. Ribosomes are little factories that send proteins to the ER. Transports materials in & outside the cell. Considered smooth or rough.

Mitochondria – organelle that converts food molecules into energy(ATP) Mitochondria – organelle that converts food molecules into energy(ATP). Powerhouse of the cell. The process of cellular _________ occurs here. respiration

Mitochondria(continue) Every type of cell has a different amount of mitochondria. There are more mitochondria in cells that have to perform lots of work, for example - your leg muscle cells, heart muscle cells etc.

Vacuole – Liquid-filled space that stores food, water, and wastes Vacuole – Liquid-filled space that stores food, water, and wastes. Larger in plant cells. Gives support - turgor pressure. .

Vacuole under the microscope

Centrioles – Helps with cell reproduction Centrioles – Helps with cell reproduction. Always found in pairs next to the nucleus

Centrioles align spindle fibers

Chloroplasts Found only in plant cells Chloroplasts Found only in plant cells. Contains green pigment (chlorophyll), that traps energy from the sun. Photosynthesis occurs here.

Cell wall Found only in plant cells Cell wall Found only in plant cells. A thick covering outside the cell membrane.

Cell wall protects the cellular contents gives support to the plant structure provides a porous medium for the circulation  and distribution of water, minerals, and other small nutrient molecules The cell wall is formed from fibrils of cellulose molecules

Lysosomes-(lysol). -contains digestive enzymes Lysosomes-(lysol) -contains digestive enzymes break down materials, such as worn out cells and bacteria.

Golgi bodies – Receives proteins from rough ER Golgi bodies – Receives proteins from rough ER. Packages and delivers proteins to needed areas.

Cytoskeleton. - made of microtubules, that give Cytoskeleton - made of microtubules, that give structure and support to the cell. -found within the cytoplasm.

Animal cell vs. Plant cell centrioles. cell wall, chloroplast Animal cell vs. Plant cell centrioles cell wall, chloroplast & larger vacuole cytoskeleton

Prokaryotic Do not have structures surrounded by membranes Few internal structures One-celled organisms, Bacteria http://library.thinkquest.org/C004535/prokaryotic_cells.html

Eukaryotic Contain organelles surrounded by membranes Most living organisms Plant Animal http://library.thinkquest.org/C004535/eukaryotic_cells.html

Differences between Eukaryotic & Prokaryotic cells Eukaryotic cells have many organelles Prokaryotic lack organelles no nucleus Eukaryotic are much larger than Prokaryotic cells Examples of Eukaryotic cells - animal & plant cells Examples of Prokaryotic cells - bacterial cells

smooth ER / mitochondria / nucleus / nucleolus / cell membrane centriole / golgi appartatus / cytoskeleton lysosomes / ribosomes / rough ER / cytoplasm mitochondria lysosomes golgi appartatus nucleolus rough ER nucleus smooth ER centriole cytoskeleton cell membrane cytoplasm ribosomes