The place where life begins Cells The place where life begins

What is a cell? A cell is the smallest functional and structural unit of all living organisms This means that cells make up all living things! An organism is any living thing All organisms are made up of cells

Itty bitty cells Most cells are too small to see with your eyes alone Why are they so small? Cells are limited by their surface area Cells take in nutrients and get rid of waste through their surface If it’s volume grows too big, there will not be enough surface area to pass nutrients and waste through

Cell Theory All organisms are made up of one or more cells The cell is the basic unit of all organisms All cells come from existing cells

Three important people to cell theory Anton van Leeuwenhoek Saw cells from pond water under a microscope Contributed to the first part of cell theory Theodor Schwann Determined animals were made of cells after Matthias Schleiden determined plants were made of cells Concluded all organisms are made of cells Concluded that the cell is the basic unit of life Rudolf Virchow Proposed that cells could only form from the division of other cells Responsible for the 3rd part of cell theory

Important Vocab Unicellular organism- 1 cell carries out all functions of life Multicellular organism – cells have specialized functions and work together for the good of the organism

What do all cells have in common? Cell membrane- a protective layer that convers the cells surface Acts as a barrier Controls movement of materials in and out of the cell Cytoplasm- the area inside of the cell Fluid Contains the organelles

Continued Organelle- small “bodies” in the cell used to preform specific functions DNA – provides the codes for the instruction of all cell processes Usually found in a membrane bound organelle called the nucleus

2 Types of Cells Prokaryotic Eukaryotic NO nucleus or membrane bound organelle DNA is located in the cytoplasm Contain ribosomes Some contain flagella Hair-like structures for movement Smaller than Eukaryotes Bacteria and Archaea Contain a nucleus and other membrane bound organelles as well as ribosomes Not all the same Make up animals, plants, protists, and fungi All multicellular organisms have eukaryotes Can be unicellular