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What are some characteristics that all living
things have?
All living things are made of cells, grow,
reproduce, respond to environments, require
nutrition, maintain homeostasis, perform
metabolic reactions
Mr. Van Roekel
11-4-14
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2.1.1 Outline the cell theory:
2.1.2 Discuss Evidence for the cell theory
2.1.3 State that Unicellular organisms carry out all the functions of life.
2.1.4 Compare the relative sizes of molecules, cell membrane thickness,
viruses, bacteria, organelles, and cells using appropriate units
2.1.5 Calculate linear magnification of drawings and the actual size of
specimens in known magnifications
2.1.6 Explain the importance of surface area to volume ratio as a factor
limiting cell size
2.1.7 State that multicellular organisms show emergent properties
2.1.8 Explain that cells in multicellular organisms differentiate to carry
out specialized functions by expressing some of their genes but not
others
2.1.9 State that Stem cells retain the capacity to divide and have the
ability to differentiate along different pathways
2.1.10 Outline one Therapeutic uses of stem cells
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Theory made up of three main points
All living things are made of one or more
cells
◦ To date, no living entity has been found that has
not been made of cells
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Two Types of organisms
◦ Multicellular Organisms – made up of many cells
and have specialized cells to carry out specific
functions
◦ Unicellular Organisms – single-celled organisms
and can carry out al functions of life independently
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Cells are the smallest unit of life
◦ Cells carry out functions of life on their own or by
various functions of organelles
◦ Parts of the cell cannot survive on their own.
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All Cells come from pre-existing cells
◦ All cells descend from common ancestor
◦ Cells multiply by division
 Mitosis & Meiosis performed by multicellular
organisms to produce daughter cells
 Binary Fission and budding performed by bacteria cells
2.1.1 Outline the cell theory
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All Living Things are made of
cells
◦ Robert Hooke- first observed cork
cells using homemade microscope.
Coined the term “cells”
◦ Antonie van Leeuwenhoek- first to
observe living cells, described them
as ‘animalcules’
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All cells come from preexisting cells
◦ Louis Pasteur- Disproved theory of spontaneous
generation. Two containers, one open to
environment, one closed. Growth only occurred in
container open to environment.
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All cells come from pre-existing cells
◦ Robert Remak- discovered/observed cell division
while studying chick embryos.
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Cells are the smallest unit of life
◦ Many cells carry out the functions of life (nutrition,
growth, reproduction, etc…)
◦ Unicellular organisms do these on own
◦ Multicellular organisms have specialized cells to
carry out all functions of life
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Discuss at least three scientists and how they
contributed to the cell theory. Discuss four
exceptions to the cell theory.
Robert Hooke – First to discover cells by looking at
cork
Antonie van Leeuwenhoek- first to observe living
cells, described them as ‘animalcules’
Robert Remak- discovered/observed cell division
while studying chick embryos.
Louis Pasteur- Disproved theory of spontaneous
generation.
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Fungal Hyphae- extremely large and multinucleated. Have a continuous cytoplasm
(acellular)
Muscle Cells – very long and multinucleated
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Unicellular Organisms (Amoeba)
◦ Atypical cells (not like normal cells) – larger than most
single celled organisms but still carries out functions of life
◦ Can one cell be “made of many cells”
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Viruses
◦ Can only reproduce using a host cell, do not perform all
functions of life. Is it living?
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Functions of life:
◦ Respiration/Metabolism – all chemical reactions in an
organism
◦ Nutrition – providing a source energy to organisms
◦ Response to environment – based on internal or
external stimulation and is essential to survival
◦ Growth and Development – may be limited but is
evident in one way or another
◦ Homeostasis – maintaining a constant internal
environment
◦ Reproduction – passing genetic material to offspring
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Unicellular organisms perform these functions on
their own
Multicellular organisms have specialized cells to
carry out these functions, but as a whole, perform
all functions of life
Plant Cell
Animal Cell
Nucleus
Bacteria
Mitochondria
100 µm
10-100 µm
3-6 µm
1-5 µm
3 µm
Virus
Ribosome
Membrane
Thickness
Molecules
100 nm
20 nm
10 nm
1 nm
2.1.4 Compare the relative sizes of molecules, cell membrane thckness,
viruses, bacteria, organelles, and cells using the appropriate SI unit.
Some units that I use & know
Unit abbr.
Metric equivalent
kilometer
km
1,000m
1 x 103m
meter
m
1m
1m
centimeter
cm
0.01m
1 x 10-2m
0.001m
1 x 10-3m
millimeter mm
micrometer
nanometer
write this
correctly
μm
0.000 001m
nm
0.000 000
001m
1x
10-6m
1 x 10-9m
To
Convert
÷ 1,000
X 1,000
X 1,000
X 1,000
μm = micrometers
We usually use this in discussion of cells.
There are 1,000μm in one mm.
2.1.5 Calculate the linear magnification of drawings and the actual size of
specimens in images of known magnification
2.1.5 Calculate the linear magnification of drawings and the actual size of
specimens in images of known magnification
2.1.5 Calculate the linear magnification of drawings and the actual size of
specimens in images of known magnification
2.1.5 Calculate the linear magnification of drawings and the actual size of
specimens in images of known magnification
2.1.5 Calculate the linear magnification of drawings and the actual size of
specimens in images of known magnification
2.1.5 Calculate the linear magnification of drawings and the actual size of
specimens in images of known magnification