Transcript Cells and Living Things

CELLS AND LIVING THINGS
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Read pp. 388-396
CELL
Smallest basic functional unit of life
 All living things are made up of one or more cells
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FOUR CHARACTERISTICS
COMMON TO
LIVING THINGS
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All living things grow
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All living things move
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Cell number increases and new cells replace old cells
Movement involves changes to shape and position or can
refer to legs and wings!
All living things respond to stimuli in their
environment
A stimulus is anything that causes a living thing to
respond
 A cat hisses; your stomach rumbles
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All living things reproduce
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Produce more of their own kind (offspring)
EXAMINING VERY SMALL LIVING THINGS
Anything smaller than 0.1mm the naked eye can’t see, so
you need a microscope
 The microscope is used by scientists to observe very small
unicellular and multicellular living things.
 Early microscopes were built in the late 1600’s.
 Anton van Leeuwenhoek was one
of the first people to build a
microscope.
 He could magnify up to 250x, and
used it to observe microscopic
living things.
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COMPOUND MICROSCOPE
The compound light microscope has
two sets of lenses that magnify an image.
 When you look through a microscope you see a
magnified, inverted and reversed image.
 Each of the objective lenses has a
different magnification power.
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Low power = 4x objective
Med power = 10x objective
High power = 40x objective
Multiply the objective by the
eyepiece for total magnification.
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Example: High Power = 40 x 10 = 400 x
MICROSCOPE FOLDABLE
Distribute a microscope image
 Add flaps to each part with the definition of each
beneath the flap.
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MICROSCOPE RESOLVING POWER
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ability to distinguish between two dots or
objects that are very close together is called
resolving power.
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human eye has a certain resolving power. You can
see the individual dots in diagrams A, B and C. The
human eye does not have the resolving power to see the
dots in diagram D.
P. 397
 Questions 1-4
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CORE LAB – SETTING UP AND USING A
MICROSCOPE
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Check your understanding
Questions 1, 2, 3, 4, 5, 6, 7, and 9
 Pause and reflect
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Read pp. 402-406
CELL PARTS
An analogy is a way to understand new ideas by
making a comparison.
 A factory can be used as an analogy for the cell.
 Parts of the cell that allow the cell to survive are
called organelles.
 Organelles take up about 5 to 30 percent of the
cell. The rest of the cell consists of water.
 Read pp. 402-403
 Do activity 10-2A, p. 404 (perhaps a class
discussion)
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THE FUNCTIONS OF CELL ORGANELLES
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The cell membrane protects the cell and selectively
regulates the movement of particles in and out of the cell.
Cytoplasm, the jelly-like substance within the cell, contains
organelles, water, and other life supporting materials.
The nucleus:
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controls all the activities within the cell.
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contains deoxyribonucleic acid (DNA).
ENERGY IN THE CELL
The mitochondria are the organelles that produce energy
in the cell.
 When the cell changes chemical energy, in the food we
eat, to energy the cell can use, it is called cellular
respiration.
 The total of all the chemical reactions that take place in
our cells is called our metabolism.
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Cellular Respiration
(c) McGraw Hill Ryerson 2007
ORGANELLES FOR ASSEMBLY,
TRANSPORT, AND STORAGE
Proteins are essential for all life
and are assembled by the
ribosomes.
 Proteins then pass through the
endoplasmic reticulum and are
placed in vesicles by the Golgi
body.
 Vacuoles are temporary storage
compartments.
 Lysosomes break down food
particles, cell wastes, and wornout organelles.
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(c) McGraw Hill Ryerson 2007
See pages 28-29
THE DIFFERENCE BETWEEN PLANT AND
ANIMAL CELLS
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Plant cells have two parts that are not found
in animal cells:
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Cell Wall
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Chloroplasts
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protects the cell and gives cell shape
change the Sun’s energy into chemical energy
Other key difference is plants have on large
vacuole whereas animal cells have several
small vacuoles.
Locate the cell wall
and chloroplast
See pages 29-30
Photosynthesis
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QUIZ!!!!
CELL THEORY
The cell is the basic unit of life.
 All organisms are composed of one or more cells.
 All cells come from other living cells.
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(c) McGraw Hill Ryerson 2007
PLANT AND ANIMAL ORGANELLES
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Organelle ~ structures of cells that perform a
specific function
Create a foldable of an animal and a plant cell
Draw a typical plant cell on a large sheet of
paper.
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Create flaps for each organelle with the definition of
each underneath
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CREATE A 3D model of a cell (class activity) p.
407
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LAB 10-2C Plant vs. Animal cells
DIVIDING CELLS
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Read p. 410-411
All cells divide during their life cycle
When cells divide, one cell becomes 2!
Your skin cells divide to replace the cells you rub off
or if you scrape yourself.
When a cell divides, the genetic material duplicates
and then divides into 2 identical sets of chromosomes
– this is called mitosis.
Each daughter cell (the new cells) gets one set of the
duplicated genetic material.
 See figure 10.10
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Only exception to this type of division is your sperm
cell and egg cells (more on this next year)
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Checking concepts...
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Questions 1-16
Test