A LOOK AT CELLS t

Microscope image: Cork image: Hooke image: ______________________ used a microscope to examine a thin slice of cork and saw “little boxes” He called them “CELLS” because they looked like the small rooms that monks lived in called Cells Robert Hooke

Microscope/Leeuwenhoek image: Animation from: ___________________________________ a Dutch microscope maker was the first to see LIVING ORGANISMS. He observed pond water and blood. Anton van Leeuwenhoek

Plant image: Schleiden image: German botanist __________________________ concluded that ALL PLANTS are made of cells Matthias Schleiden

Schwann image: Animals image: German zoologist _________________________ concluded that ALL ANIMALS ARE MADE OF CELLS Theodor Schwann

Virchow: Mitosis: German medical doctor _____________________ saw dividing cells in the microscope and reasoned that cells come from other cells Rudolph Virchow

CELL THEORY the ideas of Schleiden, Schwann, and Virchow. The cell theory consists of three principles: 2. All organisms are ________________________ 1.Cells are the basic units of _____________. 3. Cells arise from ____________ cells. Cell image: made of one or more cells. existing all life

CELLS DIFFER IN : Size Shape Function

CELL SIZE Typical cells range from: 5 – 50 micrometers (microns) in diameter

How big is a micron ( µ ) ? 1 cm = 10,000 microns 1” = 25,000 microns

All living things are made of cells BUT… organisms can be very different. UNICELLULAR one-celled MULTICELLULAR many-celled Image from:

MULTICELLULAR ORGANISM don’t just contain MANY CELLS. Image from: They have different kinds of cells doing different jobs

Cells in a multi-cellular organism become SPECIALIZED Image from: Cell Specialization =DIFFERENTIATION

SPECIALIZED ANIMAL CELLS Muscle cells Red blood cells Cheek cells

Specialized Plant cells Guard cells Xylem cells Pollen Guard cells: Xylem: Pollen:

________  __________  ___________  ATOMS MOLECULESORGANELLES IMAGE SOURCES: see last slide Levels of organizations in organisms:

____________  CELLSTISSUES IMAGE SOURCES: see last slide Similar cells working together

___________  __________  ___________ ORGANS ORGAN SYSTEMS ORGANISM IMAGE SOURCES: see last slide Different tissues working together Different organs working together