Lesson 2: Cell Theory Flashcards
Who was the earliest recorded scholar to articulate the Spontaneous Generation Theory?
Aristotle (384 – 322 BC)
What is the Spontaneous Generation Theory?
It is the theory that life spontaneously arose from inanimate matter.
Who proposed that mice could arise from rags and wheat kernels left in an open container for 3 weeks?
Jan Baptista van Helmont (1600).
Where does life come from?
Religion (God), Philosophy (self-worth), and Science (facts and evidence) have all wrestled with this question.
What did Aristotle say about life and nonliving matter?
He said, “life can arise from nonliving matter.”
What was Francesco Redi’s contribution to disproving spontaneous generation?
He performed an experiment in 1668 showing that maggots did not spontaneously generate on meat left out in the open air.
What was John Needham’s argument regarding spontaneous generation?
He argued that microbes arose spontaneously after boiling broth infused with plant or animal matter.
How did Lazzaro Spallanzani challenge Needham’s conclusions?
Spallanzani performed experiments showing that life was not introduced from the air but from microorganisms in the air.
What was Louis Pasteur’s significant contribution to disproving spontaneous generation?
He filtered air through a gun-cotton filter and found microorganisms, suggesting that exposure to air introduced microorganisms rather than a “life force.”
What is the phrase “Omne vivum ex vivo” and what does it mean?
It means “Life only comes from life.”
Who discovered cells in a slice of cork and named them “cells”?
Robert Hooke (1665).
What did Antoine van Leeuwenhoek discover with his microscope?
He observed red blood cells, sperm, and single-celled organisms, and discovered the nucleus.
What did Robert Brown conclude about the nucleus in 1831?
He theorized that the nucleus is a fundamental and constant component of the cell.
What did Matthias Schleiden state about plants?
He stated that all plants are composed of cells.
What did Theodore Schwann conclude about animals?
He concluded that all animals are composed of cells.
What is the Cell Theory as proposed by Schleiden and Schwann?
All living things are composed of cells.
What did Rudolph Virchow theorize about cells in 1858?
He theorized that all living cells come from pre-existing living cells.
What does “Omnis cellula e cellula” mean?
“All cells come from already existing cells.”
What did Felix Dujardin discover about cells?
He concluded that cells are not hollow but filled with a jelly-like substance known as protoplasm.
What did Ludolf Christian Treviranus say about cells?
He said that cells can be divided.
What are the three main principles of Cell Theory?
- All living things are composed of one or more cells. 2. All living cells come from other living cells by cell division. 3. Cells are the basic units of structure and function in organisms.
What does it mean that cells are the “monomer” of any organism?
It means that cells are the fundamental building blocks of all living organisms.
It is one of the explanations to the question “where does life come from”?
Spontaneous Generation Theory
When did the Spontaneous Generation Theory persisted?
17th Century
