Documents BIO 1140
Cells: Structure and varieties
-All living things (organism) are built from cells
Cell: a small membrane bound unit filled with a concentrated aqueous solution of chemicals
with reproduction capacity.
Biology is important for agriculture
-Dependence on other organisms
-Agriculture began 10 000 years ago
-Advance in crop production
-Genetics Engineering for climate challenges
Cell differs in size
E. coli is 1 micrometre
Frog egg is 1 micrometre
Most cell is 1-100 micrometre
Eukaryotic cell is 10-100 micrometre diameter
Why are cells small and large organisms made if many small cells?
To function, cells must maintain a large surface area to volume ratio
-When the cell gets bigger it needs gets more important.
If the cell volume is too big, but the surface is not too big to exchange that material, the cell
cant function.
-Accumulation of waste
Cells comes in a variety of shapes
Cell also differs in nutritional requirements
Cells became visible in the 17th century
, Robert Hook (put 2 lenses together) (1665)
Quark, a plant tissue
Anton, Van (1670) observed living organisms
Cell biology emerged by the publication of Matthias Shleiden (1838) -all plants are made of
cells, Shwann- all living things are made up of cells.
The cell Theory (1838)
Cells are the fund unit of life
All living organisms are composed of cells
Original theory
Modern cells evolve from a common ancestor
In light microscopes glass lenses and visible light are used to form an image
Light and electric microscopes
Magnification (1000X), resolution 200nm
See living cells
Bright field microscopy
Background is bright, hardly distinguish the cells
Phase contrast microscopy
Contrast is increased, this enhances light and dark regions in the cell and make it easier to
see details
Differential interference- contrast microscopy, 2 beams of polarized light
Stained bright-field microscopy a stain enhances contrast and reveal details
Cells: Structure and varieties
-All living things (organism) are built from cells
Cell: a small membrane bound unit filled with a concentrated aqueous solution of chemicals
with reproduction capacity.
Biology is important for agriculture
-Dependence on other organisms
-Agriculture began 10 000 years ago
-Advance in crop production
-Genetics Engineering for climate challenges
Cell differs in size
E. coli is 1 micrometre
Frog egg is 1 micrometre
Most cell is 1-100 micrometre
Eukaryotic cell is 10-100 micrometre diameter
Why are cells small and large organisms made if many small cells?
To function, cells must maintain a large surface area to volume ratio
-When the cell gets bigger it needs gets more important.
If the cell volume is too big, but the surface is not too big to exchange that material, the cell
cant function.
-Accumulation of waste
Cells comes in a variety of shapes
Cell also differs in nutritional requirements
Cells became visible in the 17th century
, Robert Hook (put 2 lenses together) (1665)
Quark, a plant tissue
Anton, Van (1670) observed living organisms
Cell biology emerged by the publication of Matthias Shleiden (1838) -all plants are made of
cells, Shwann- all living things are made up of cells.
The cell Theory (1838)
Cells are the fund unit of life
All living organisms are composed of cells
Original theory
Modern cells evolve from a common ancestor
In light microscopes glass lenses and visible light are used to form an image
Light and electric microscopes
Magnification (1000X), resolution 200nm
See living cells
Bright field microscopy
Background is bright, hardly distinguish the cells
Phase contrast microscopy
Contrast is increased, this enhances light and dark regions in the cell and make it easier to
see details
Differential interference- contrast microscopy, 2 beams of polarized light
Stained bright-field microscopy a stain enhances contrast and reveal details
