Chapter 1 - Cells: Discovery & Exploration

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Chapter 1: Cells -Discovery & Exploration

Nature of Biology 1

Chapter 1

Pages 2-21

Chapter 1 - Cells: Discovery & Exploration

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Cells & Microscopes

Cells are the basic structural and functional units of all living things.

Although most cells are too small to be seen with the unaided eye, microscopes give enlarged images of cells and their structures.

Fig 1.4 – Examples of Cells p4

Chapter 1 - Cells: Discovery & Exploration

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Chapter 1 - Cells: Discovery & Exploration

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Cells“An Historical Overview”

Cells were first identified and named by Robert Hooke in 1665.

The Cell Theory arose in the mid 1800’s.

Cell Theory – “All living things consist of one or more organised structures that are called cells or products of cells. Cells are the basic functional unit of life.”

Quick Check Questions 2, 3,4,6,7 p9

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Quick-check page 9

2. Who was credited with the discovery of the basic building blocks of life?

A: Robert Hooke 3. Who is credited with the discovery of the cell nucleus? A: Robert Brown 4. What was the important contribution by Schleiden and

Schwann to Biology? A. They created the cell theory:

All living things consist of one or more organised structures called cells or products of cells.

Cells are the basic functional unit of life.

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Quick Check cont…

6. Which person is more likely to have permanent damage after an accident: person A who survives after blood loss or person B who survives after some loss of brain tissue? Explain.

A. Person B. This is because blood cells are constantly replaced by the body. In contrast, brain cells are not replaced during a person’s lifetime. Therefore, person B cannot reproduce new brain cells and is more likely to have permanent damage than person A.

7. How many micrometres (µm) are there in a millimetre? A. 1000

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Tools for viewing cells

Various types of microscopes can be used to examine cells.

Light microscopes (LM’s) reveal details about the arrangement of cells and the internal structure of cells. Fig 1.9

Phase contrast microscopes allow the study of unstained living cells. Fig 1.11

Fluorescence microscopes reveal details of chemical substances present in cells. Fig 1.12

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Tools for viewing cells

Chapter 1 - Cells: Discovery & Exploration

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Tools for viewing cells

Transmission electron microscopes (TEM’s) reveal fine detail of the internal structure of cells.

Scanning electron microscopes (SEM’s) reveal details of cell surfaces.