Cells: The Basic Unit of Life

Organization of Life  Everything has a least one cell  Many living things exist as only one cell  Other living things may have trillions of cells

What is the world ’ s largest cell?

The egg!  The first cell of a chicken is the yolk with a tiny white dot in it.  It is surrounded by a clear jellylike fluid called egg white.  The white dot divides over and over again to become a chick.

 We are made up of about 100 trillion cells.  We have about 200 different kind of cells and each is specialized to do a particular job  Examples: blood cells, bone cells, nerve cells, skin cells

Tissue  A group of cells working in a team to perform a specific job.  The material around and between the cells is also part of the tissue.  Examples: blood, fat, muscle

Organs  When two or more tissues work together to perform a specific job, the group of tissue is called an organ.  Examples: stomach, intestines, heart, lungs, skin

 Plants have different kinds of tissues that work together.  The leaf is a plant organ, so is the stem and roots.

Organ Systems  Organs working together to perform particular jobs.  Examples: digestive system, respiratory system,

Organisms: Independent Living  Anything that can live on its own is an organism.  A single cell living on its own is called unicellular.  An organism that exist only as a group of cells is called multicellular.

Populations  A group of organisms of the same kind living in the same area.  Examples: deer population in a forest, people in a specific town or city, oak trees in a forest

Communities  Two or more populations living in the same area  Example: foxes, oak trees, lizards, flowers, and many more make up the forest community.  People, dogs, cats, and many more organism make your hometown community

Ecosystem  It is the community and all of the nonliving things that effect it, such as water, soil, temperature, and light.

Complete the following sentence.  Cells are related to _____________ in the same way that _____________ are related to organ system.

Cell Theory  In 1839 Theodor Schwann wrote the first two parts of the cell theory: All organisms are composed on one or more cells. The cell is the basic unit of life in all living things. In 1858 Rudolf Virchow wrote the third theory: All cells come from existing cells.

What do all cells have?  Cell membrane- controls the passage of materials in and out of the cell  DNA-controls all the activities of the cell and contains the information need for new cells.  Cytoplasm-the fluid and almost everything in it  Organelles-structures within the cell

Two Types of Cells  Prokaryotic No nucleus No membrane covered organelles Circular DNA Bacteria  Eukaryotic Nucleus Membrane covered organelles Linear DNA All other cells

Animal Cell

Organelles in Animal Cell  Cell membrane  Lysosomes  Nucleus  Nucleolus  Nuclear membrane  vacuoles  mitochondria  Golgi body  Cytoplasm  Ribosomes  Smooth ER  Rough ER  centrosomes

Plant Cell

Organelles In Plant Cell Organelles in yellow are only found in plant cells Cell wall Cell membrane Vacuoles (large) NucleusNucleolus Nuclear membrane ChloroplastsmitochondriaCytoplasmAmyloplastCentrosome Rough ER Smooth ER Ribosomes Golgi body

Bacteria Cells

Structure of Bacteria Cell

Nucleolus  The nucleolus primary function is to assemble ribosomes, is the largest structure in the cell nucleus.