Ch6 Cells - A tour of the Cell Chapter 6 PowerPoint...

Info iconThis preview shows pages 1–13. Sign up to view the full content.

View Full Document Right Arrow Icon
Click to edit Master subtitle style 11/10/10 A tour of the Cell Chapter 6 PowerPoint Lectures for Biology 8th edition Neil Campbell and Jane Reece Lectures by Chris Romero, updated by Erin Barley with contributions by Joan Sharp
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
11/10/10 Overview: The Fundamental Units of Life Living organisms are distinguished from non-living organisms because they are made up of cells. l All organisms are made of cells Cells were first described by Robert Hooke in 1665 Cell structure is correlated to cellular function l Structure and function….again!
Background image of page 2
11/10/10 The Fundamental Units of Life Cells are the underlying unity of life Theme : Cells are an organism’s basic units of structure and function l The cell is the lowest level of organization that can perform all activities required for life – most basic living units 1838/1839 Mattias Schleiden and Theodor Schwann l All cells come from other cells 1855 Rudolph Virchow observes cells dividing
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
11/10/10 Concept 6.1: To study cells, biologists use microscopes and the tools of Though usually too small to be seen by the unaided eye, cells can be complex Scientists use microscopes to visualize cells too small to see with the naked eye In a light microscope (LM) , visible light passes through a specimen and then through glass lenses, which magnify the image l Several lenses = compound microscope
Background image of page 4
11/10/10 Cell Size
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
11/10/10 Observing Cells The quality of an image depends on l Magnification , the ratio of an object’s image size to its real size l Resolution , the measure of the clarity of the image, or the minimum distance of two distinguishable points l Contrast , visible differences in parts of the sample
Background image of page 6
11/10/10 Observing Cells Image of pollen grain with good resolution (left) and poor resolution (right) Image of pollen grain with good contrast (left) and poor contrast (right) http://science.howstuffworks.com/light- microscope.htm/printable
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
11/10/10 Observing Cells § Microscopes § Light microscope § Brightfield (used in lab) § Fluorescent microscopes § Use fluorescent stains to identify specific structures or molecules within cells § Electron microscopes § Transmission (TEM) § Great magnification and resolution § Thin sections of specimen § Scanning (SEM) § Great magnification and resolution § Give 3-D picture of external features and shape Least detail provi ded Most detail provi
Background image of page 8
11/10/10 Observing Cells Light microscopes can magnify effectively to about 1,000 times the size of the actual specimen l Various techniques enhance contrast and enable cell components to be stained or labeled l Most subcellular structures, including organelles (membrane-enclosed compartments), are too small to be resolved by an LM
Background image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
11/10/10 Observing Cells
Background image of page 10
11/10/10 Observing Cells
Background image of page 11

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
11/10/10 Observing Cells Two basic types of electron microscopes (EMs) are used to study subcellular structures Scanning electron microscopes (SEMs) focus a beam of electrons onto the surface of a
Background image of page 12
Image of page 13
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 90

Ch6 Cells - A tour of the Cell Chapter 6 PowerPoint...

This preview shows document pages 1 - 13. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online