Cell PEOPLE, Cell Size, and Cell Specialization Chap 7-1 & 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. 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 1. All living things are ________________________. 2. Cells are the basic unit of ____________ & _____________ in an organism. (cell = basic unit of _____________) 3. Cells come from the reproduction of ____________ cells Cell image: MADE OF CELLS existing life STRUCTURE FUNCTION

American Biologist _____________________ provides evidence for the idea that certain organelles within cells were once free-living cells themselves. = _________________________ Lynn Margulis ENDOSYMBIOTIC THEORY

Evidence for Endosymbiotic theory 1.Mitochondia and chloroplasts have circular_______ similar to bacteria. 2. Mitochondria and chloroplasts have ______________ whose size and structure resemble bacterial ribosomes. 3. Mitochondria and chloroplasts replicated using _________________ like bacteria. 4. _______________________ of mitochondria and chloroplasts have a composition similar to bacterial membranes. DNA Binary fission RIBOSOMES INNER MEMBRANES

All living things made of cells BUT… organisms can be very different. UNICELLULAR MULTICELLULAR Image from:

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

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 by turning different genes on and off 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

____________  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