Transcript Cells: The Basic Unit of Life

Cells: The Basic
Unit of Life
Organization of Life
 Everything has a least one cell
 Many living things exist as only one cell
 Other living things may have trillions of
cells
What is the world’s
largest cell?
The egg!
 The first cell of a chicken is the yolk with
a tiny white dot in it.
 It is surrounded by a clear jellylike fluid
called egg white.
 The white dot divides over and over
again to become a chick.
 We are made up of about 100 trillion
cells.
 We have about 200 different kind of cells
and each is specialized to do a particular
job
 Examples: blood cells, bone cells, nerve
cells, skin cells
Tissue
 A group of cells working in a team to
perform a specific job.
 The material around and between the
cells is also part of the tissue.
 Examples: blood, fat, muscle
Organs
 When two or more tissues work together
to perform a specific job, the group of
tissue is called an organ.
 Examples: stomach, intestines, heart,
lungs, skin
 Plants have different kinds of tissues that
work together.
 The leaf is a plant organ, so is the stem
and roots.
Organ Systems
 Organs working together to perform
particular jobs.
 Examples: digestive system, respiratory
system,
Organisms: Independent
Living
 Anything that can live on its own is an
organism.
 A single cell living on its own is called
unicellular.
 An organism that exist only as a group of
cells is called multicellular.
Populations
 A group of organisms of the same kind
living in the same area.
 Examples: deer population in a forest,
people in a specific town or city, oak
trees in a forest
Communities
 Two or more populations living in the
same area
 Example: foxes, oak trees, lizards,
flowers, and many more make up the
forest community.
 People, dogs, cats, and many more
organism make your hometown
community
Ecosystem
 It is the community and all of the
nonliving things that effect it, such as
water, soil, temperature, and light.
Complete the following
sentence.
 Cells are related to _____________ in
the same way that _____________ are
related to organ system.
Cell Theory
 In 1839 Theodor Schwann wrote the first
two parts of the cell theory:
All organisms are composed on one or
more cells.
The cell is the basic unit of life in all living
things.
In 1858 Rudolf Virchow wrote the third
theory:
All cells come from existing cells.
What do all cells have?
 Cell membrane- controls the passage of
materials in and out of the cell
 DNA-controls all the activities of the cell
and contains the information need for
new cells.
 Cytoplasm-the fluid and almost
everything in it
 Organelles-structures within the cell
Two Types of Cells
 Prokaryotic
No nucleus
No membrane covered
organelles
Circular DNA
Bacteria
 Eukaryotic
Nucleus
Membrane covered
organelles
Linear DNA
All other cells
Animal Cell
Organelles in Animal Cell
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Cell membrane
Lysosomes
Nucleus
Nucleolus
Nuclear membrane
vacuoles
mitochondria
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Golgi body
Cytoplasm
Ribosomes
Smooth ER
Rough ER
centrosomes
Plant Cell
Organelles In Plant Cell
Organelles in yellow are only found in plant cells
Cell wall
Cell membrane
Vacuoles (large)
Nucleus
Nucleolus
Nuclear membrane
Chloroplasts
mitochondria
Cytoplasm
Amyloplast
Centrosome
Rough ER
Smooth ER
Ribosomes
Golgi body
Bacteria Cells
Structure of Bacteria Cell
Nucleolus
 The nucleolus primary function is to
assemble ribosomes, is the largest
structure in the cell nucleus.