Ch. 4 - Cell Theory

Question 1

Robert Hooke

Answer 1

looked at piece of cork under a microscope and compared what he saw to cellulae (“little rooms”)

Question 2

Anton van Leeuwenhoek (2)

Answer 2

• looked at and described all sorts of living cells

- human blood and sperm, pond water and more

Question 3

first cell theory

Answer 3

“all living things are composed of living cells”

Question 4

Rudolph Vichow (2)

Answer 4

• extended cell theory to also include that: “all living cells arise from pre-existing cells” (biogenic law)
• prior to this life was thought to generate spontaneously from nonliving matter

Question 5

Louis Pasteur’s Experiment - Treatment A (3)

Answer 5

• add nutrient broth to flasks with straight necks
• sterilize the broth
• leave open to air so “life” cam fall into it

Question 6

Louis Pasteur’s Experiment - Treatment B (3)

Answer 6

• add nutrient broth to flasks with curved necks and cotton
• sterilize the broth
• leave open to air, but prevent “life” from falling into it, then remove curved piece and cotton and “life” grows

Question 7

August Fredrich Leopold Weismann (3)

Answer 7

• added important component to the biogenic law: “cells living today trace their ancestry back to ancient times”
• there must be a common ancestral cell
• further postulated that germ-plasm was hereditary material and only changes to germ cells and not body cells could be inherited

Question 8

current cell theory (3)

Answer 8

• all living things are made of cells
• a cell is the smallest unit in a living thing
• all cells come from other cells