130 likes | 243 Views
The Cell Theory. Biology 11 Cell Biology Chapter 1. The Cell pages 8-10. smallest living unit Basic building block of organisms Human body – 100 trillion cells Different cells are specialized to preform different tasks. Nerve Cells.
E N D
The Cell Theory Biology 11 Cell Biology Chapter 1
The Cellpages 8-10 • smallest living unit • Basic building block of organisms • Human body – 100 trillion cells • Different cells are specialized to preform different tasks
Nerve Cells • Transmit messages to the body about our surroundings and enable us to respond. • Vision, hearing, taste, smell and touch all depend on nerves.
Muscle Cells • Capable of rapid contraction. • Grouped together to form our muscle groups.
Red Blood Cells • Transport of Oxygen
White Blood Cells • Defense against disease.
Special Receptor Cells • Communicate messages to nerves for relay to nerve centres like the brain.
Our Body – a living ecosystem of cells • E. coli bacteria in our “gut”. • We breathe in plant spores and pollen. • Microbes and microscopic animal eggs on the food we eat. • All made of cells! • Outside has cells too – fungus and bacteria.
Cells in Daily Life • Yogurt bacteria • Sour milk bacteria • Cheese processing • Yeast cells for bread and beer making • Leather tanning processes
All cells ……… • Digest nutrients • Excrete wastes • Synthesize needed chemicals • reproduce
Cells are…. • The basic unit of all living things! • Grouped together to form tissues and organs.
Cell History • Robert Hooke, 1665, borrowed the word cell (reminded him of the “cells” in a monastery) to describe the honeycomb shape and structure of a thin slice of cork he observed under a primitive microscope. • Robert Hooke • Neglected Hooke • Anton Van Leeuenhoek, 1674 An Unlikely Scientist, made microcsopes and observed blood cells, bacteria and single celled organisms. • Robert Brown, 1831, described the nucleus • Theodor Schwann and Mathias Schleiden, 1838, plant and animal tissue composed of cells • Louis Pasteur, – Very Important Person! studied microorganisms. • Rudolph VIrchow, 1858, “All cells come from preexisting cells.”
Modern Cell Theory • All living things are composed of one or more cells. • The cell is the smallest entity that retains the properties of life. • New cells arise only from cells that already exist. • An expansion….More to the story!