Cell Theory and Scientific Principles

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Questions and Answers

In scientific language, how is a theory defined?

A guess that is often wrong

An idea that has yet to be proven

A hypothesis waiting for testing

A well-substantiated explanation based on repeated observations (correct)

In daily language, a theory is regarded as a well-established fact.

False

What does it mean for a theory to be 'repeatedly confirmed'?

It means the theory has been shown to be true multiple times through observation and experimentation.

In scientific language, a theory is based on a body of __________, not opinion.

facts Signup and view all the answers

Match the following scientific theories with their descriptions:

Endosymbiosis = Explains how eukaryotic cells originated Hydrogen bonding = Describes the attraction between molecules with hydrogen Semiconservative DNA replication = Explains how DNA copies itself Natural selection = Describes the process by which species adapt to their environment Signup and view all the answers

Which of the following statements is NOT a part of the cell theory?

Cells can spontaneously generate from nonliving matter. Signup and view all the answers

Viruses are considered living things according to the cell theory.

False Signup and view all the answers

What does 'basic' refer to in the context of the cell as the basic unit of life?

Foundation or starting point; fundamental. Signup and view all the answers

All ____ things are composed of cells.

living Signup and view all the answers

What process do prokaryotic cells undergo to divide?

Binary fission Signup and view all the answers

All observed cells have come from preexisting cells.

True Signup and view all the answers

Outline one piece of evidence that supports the cell theory.

Repeated observations and experiments have shown that cells come from preexisting cells. Signup and view all the answers

Match the following organisms with their classification according to the cell theory:

Bacteria = Living Fungi = Living Plants = Living Viruses = Not living Signup and view all the answers

Who discovered cells in 1663?

Robert Hooke Signup and view all the answers

Matthias Schleiden proposed that all animals are made of cells.

False Signup and view all the answers

What invention did Zacharias Jansen create in 1590?

compound microscope Signup and view all the answers

_____ invented the modern compound microscope in 1886.

Ernst Abbe and Carl Zeiss Signup and view all the answers

Match the following scientists with their achievements:

Robert Hooke = Discovered cells Theodore Schwann = Realized all animals are made of cells Matthias Schleiden = Realized all plants are made of cells Rudolf Virchow = Proposed that all cells come from other cells Signup and view all the answers

What significant discovery did Anton von Leeuwenhoek make in 1674?

He discovered unicellular organisms Signup and view all the answers

The scanning electron microscope was invented in 1935.

True Signup and view all the answers

In what year did Rudolf Virchow propose that all cells come from other cells?

1855 Signup and view all the answers

Study Notes

The Cell Theory

The cell is the basic unit of life. "Basic" means fundamental or foundational.
All living things are composed of cells.
Cells come from pre-existing cells.

Subcellular Components

Cells are alive
Subcellular components (like organelles) are not alive.

Evidence Supporting the Cell Theory

Repeated observations and experiments support the cell theory.
Observation has consistently shown the cell theory to be true.
Subcellular components have never been observed to carry out life processes.
Studies from the 17th century to present have shown every biological specimen/tissue consists of one or more cells.
Spontaneous generation has never been observed.

Scientific Theories

Scientific theories are well-substantiated explanations of natural phenomena.
Scientific theories are based on large amounts of evidence obtained through experiments and observations. Theories are NOT guesses or opinions.
Scientific theories are repeatedly confirmed.
Other scientific theories in IB Biology include endosymbiosis, hydrogen bonding, the semi-conservative nature of DNA replication, natural selection, and chemiosmosis.

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Description

Explore the fundamental concepts of cell theory and its implications for understanding life. This quiz covers the basics of cellular structure, the distinction between living cells and subcellular components, and the historical evidence supporting these scientific principles. Test your knowledge on the foundational theories that govern biology.