LEARNING GOALS:
-Use terminology related to living things
-Explain the importance of cell specialization
-Explain link between specialized cells, tissues, organs,
and organ systems
SUCCESS CRITERIA:
 Define: cell specialization, stem cell
 Use a flowchart to explain the link between specialized cells,
tissues, organs, and organ systems
 List the factors that influence cell specialization in animals
 List types of tissues in animals
 Discuss ethical/societal concerns about stem cells
CELLS, TISSUES, ORGANS,
SYSTEMS
-Levels of Organization
-Types of cells
-Types of tissues
-Cell Differentiation
-Stem cells
MINDS-ON
https://www.youtube.com/watch?v=BmFEoCFDi-w
Cell Specialization
 A society relies on its specialists to function efficiently/properly.
 Similarly, a multicellular organism relies on different types of cells
to function efficiently/properly.
Blood Cell
Bone Cell
Muscle Cell
Brain Neuron
 Specialized Cells – a cell that can perform a specific function
 In order to effectively perform their specialized functions, cells
have developed specific physical and chemical characteristics that
best suit their role.
i.e.
Muscle cells require large amounts of energy, thus they contain a
lot of mitochondria
Cells that produce mucous in the intestine have a lot of Golgi
bodies
Levels of Organization
 Unicellular organisms (i.e. Bacteria, algae etc...) are able to function
independently without the direct help of other cells
 However, the specialized cells within multicellular organisms (i.e. bone cell,
blood cell etc...) would not survive long if they became separated from their
surrounding cells.
 The cells within multicellular organisms are organized into a
hierarchy.
 Only by working together as a whole organism can
these specialized cells survive and reproduce.
Levels of Organization
Organ
Systems
Organs
Tissues
Cells
 TISSUE
o A collection of similar cells that perform a specific function.
o In animals, there are FOUR types:
 ORGANS
o A structure composed
of different tissues
working together to
perform a complex
body function
o Common organs in
animals include:
Heart / Stomach /
Lungs / Kidneys / Liver
/ Eyes / Brain /
Intestines / Skin
 ORGAN SYSTEMS
o A system of one or more organs and structures that work
together to perform a major vital body function such as
digestion or reproduction.
o Most organs work within a single organ system.
i.e. The stomach is part of the digestive system
o
Some organs may play a
role in more than one
system.
i.e. The pancreas is part
of the digestive system,
as well as the endocrine
system (glands that
regulate the body by
secreting hormones into the
bloodstream).
Human Organ Systems
Cellular Differentiation
 All multicellular organisms begin life as a single cell zygote
(fertilized egg) .
 As it undergoes a series of cell divisions, the cells are said to be in
the process of cellular differentiation.
 This is where they begin to show specialization in their shape,
contents, and function. The zygote is now called an embryo.
FUN FACTS: Did you know...?
 During the early stages
of embryonic
development, many
vertebrates (animals
with a backbone) have
remarkably similar
forms/structures.
Stem Cells
https://www.youtube.com/watch?v=evH0I7Coc54
Stem Cells
 In animals, a cell that can differentiate into many different cell
types is called a stem cell.
 Depending on the type of
nutrients it receives and
other environmental
factors, different parts of
its DNA can be turned on
or off.
 This results in the
formation of specific type
of cell/tissue.
Stem Cell Research
 In general, there are two types of stem cells:
1. Embryonic Stem Cells:
Stem cells that are harvested early enough in the embryonic
stage, so that they can be differentiated into any kind of cell.
i)
Early embryonic stem cells:
Totipotent = capable of dividing and forming into a complete
mature organism
ii) Late embryonic stem cells:
Pluripotent = capable of developing into many different cell types
2) Tissue/Adult Stem Cells:
Harvested from the specialized tissue of mature organisms. These cells
can only differentiate into certain types of cells.
i.e.
Tissue stem cells from the bone marrow can differentiate into white
blood cells, red blood cells, or platelets.
This procedure is often used to treat patients with Leukemia or other
cancers that affect blood cells.
 Research in the field of stem cells holds great promise for
organ/tissue transplants and regeneration. But it’s not without
its controversies.
 However, since the umbilical cord contains a rich supply of tissue
stem cells, some parents will have their child’s umbilical cords
stored in a blood bank for future use
THINK-PAIR-SHARE
What are some
ethical, legal,
and social issues
associated with
STEM CELLS?
Next Class…
• Looking at animal and plant cells under the microscope!
LEARNING GOALS:
-Investigate specialized cells in the human body (or in plants)
-Draw labelled biological diagrams
SUCCESS CRITERIA:
 Use a microscope to differentiate between animal and plant cells
 Draw biological diagrams of plant and animals cells using checklist provided