THE CELL

Cell Theory All organisms are composed of cells All cells come from pre-existing cells Cells are the basic unit of structure and function of all organisms

Organelles Special structures in a cell that carry on the life functions of a cell Special structures in a cell that carry on the life functions of a cell The “organs” of an individual cell

There are two types of cells found in all organisms Prokaryotic Cells- – small considered primitive Eukaryotic Cell – – up to 10x larger,more advanced

Prokaryotic vs Eukaryotic Found only in Kingdoms Archaebacteria, and Eubacteria No “true” nucleus No “true” organelles Found in Kingdoms Protista, Fungi, Plantae, and Animalia Posses a “true” nucleus with genetic material (DNA) Posses true organelles

Basic Cell Anatomy 3 Main Parts of a Cell –Nucleus –Plasma Membrane surrounds the cell –Cytoplasm where the organelles are located where the organelles are located

Nucleus (the Boss of the cell) Functions of the Nucleus –Controls all cell activities –Stores hereditary info. in the form of DNA  DNA has the coded information for making the proteins and other substances important to the life of the cell

Parts of the Nucleus (pg.181) Nuclear envelope- surrounds and encloses the nucleus (absent in prokaryotic cells) Nuclear pores- holes in the nuclear envelope that allows “stuff” into or out of the nucleus Chromatin- made up of DNA and protein Nucleolus- Dark dense structure in the middle of the nucleus that produces ribosomes

THE NUCLEUS Chromatin Nuclear Envelope Nucleolus Nuclear pore

The Plasma Membrane Thin barrier around a cell that controls what enters and leaves a cell. Cytoskeleton- found in the plasma membrane it is a system of tubules and fibers that support the cell and maintain its shape Parts of the cytoskeleton also functions in locomotion of the cell (Ex. cilia and flagella)

Cilia and Flagella Cilia- short hair-like projections that row the cell through the water Flagella- long whip-like projections that propel a cell through the water. CILIA

Cytoplasm The liquid part of the cell located between the nucleus and the plasma membrane The liquid part of the cell located between the nucleus and the plasma membrane Contains the (where most activities of the cell occur) Contains the organelles (where most activities of the cell occur)

Organelles in the cytoplasm pp Ribosomes Endoplasmic reticulum GolgiLysosomesVacuoles Mitochondria and Chloroplasts

Ribosomes Small bead-like organelles found floating in the cytoplasm, called free ribosomes, or attached to the endoplasmic reticulum, called attached ribosomes.

Function of ribosome Where proteins are made –Receives the information from the nucleus –Free ribosomes proteins made there are for use in the cell. –Bound ribosomes proteins made there are for export outside the cell. –Cells that are active in protein production are often packed with ribosomes.

Endoplasmic reticulum (ER) Folded membrane where parts of the cell membrane are made and proteins are constructed

Two types of Endoplasmic Reticulum 1. Rough ER- Called rough ER because it has ribosomes attached to its outer surface where proteins for export and membranes are made. 2. Smooth ER- makes lipids and detoxifies drugs and poisons

The Golgi Stacks of flattened sacs found in the cytoplasm Function- modifies, sorts, packages and routes the products of the ER Often called the “warehouse” of the cell The manThe apparatus

Lysosomes Small liquid filled compartments in the cell –Function- contain digestive enzymes to breakdown material needed by the cell –Also- digest old worn out organelles (recycling of “old” cell parts)

Golgi and Lysosomes

Vacuoles Provides storage for water, salts, and food for the cell. Food Vacuole

Mitochondria Generate energy for the cell Often called the “powerhouse” of the cell

Chloroplasts Found only in plant cells. They capture light energy and convert it into chemical energy in the form of glucose. This process is called photosynthesis.

Cell wall Found only in plant cells and Fungi Helps support and protect the cell.

THE CELL