Daily Entry

• 1. A specialized cell that functions in sending chemical and electrical signals is?

• 2. A living plant specialized cell that transports sugar?

• 3. Blood cells with nuclei are referred to as?• 4. A specialized cell that has a lot of

mitochondria and a flagellum for movement?• 5. An unspecialized cell?

Stem Cells

Video

(Both links are to the same video, try the other if one doesn’t work)

• http://www.eurostemcell.org/films/a-stem-cell-story/English

• http://www.youtube.com/watch?v=2-3J6JGN-_Y

Introducing stem cells

Stem cell biology basics

A life story…

What is a stem cell?

Identical stem cells

Stem cell

SELF-RENEWAL(copying)

Stem cell

Specialized cells

DIFFERENTIATION(specializing)

Stem cell= an undifferentiated cell that has not been given a specific job or function yet, once it is given a specific job it is then differentiated/specialized

1 stem cell

Self renewal - maintains the stem cell pool

4 specialized cells

Differentiation - replaces dead or damagedcells throughout your life

Why self-renew AND differentiate?1 stem cell

Where are stem cells found?

1. embryonic stem cellsblastocyst - a very early

embryo

2. tissue stem cellsfetus, baby and throughout life

Types of stem cell:1) Embryonic stem cells

Embryonic stem (ES) cells:Where we find them

blastocyst

outer layer of cells= ‘trophectoderm’

cells inside = ‘inner cell mass’

embryonic stem cells taken fromthe inner cell mass

culture in the labto grow more cells

fluid with nutrients

Embryonic stem (ES) cells:What they can do

embryonic stem cells

PLURIPOTENT- capable of developing into any type of cell, these are very important to research

all possible types of specialized cells

differentiation

neuronsgrow under conditions B

Embryonic stem (ES) cells:Challenges

embryonic stem cells

skin

grow under conditions A

blood

grow under conditions C

liver

grow under conditions D

?

Types of stem cell:2) Tissue stem cells

Tissue stem cells:Where we find them

muscles

skin

surface of the eye brain

breast

intestines (gut)

bone marrow

testicles

Tissue stem cells:What they can do

MULTIPOTENT-can give rise to other types of cells but it is limited in its ability to differentiateEx:Bone marrow also contains multipotent stem cells that give rise to all blood cell types but not any other type of specialized cells

blood stem cell

found in bone marrow

differentiation

only specialized types of blood cell:red blood cells, white blood cells,

platelets

Pros vs. Cons

• Transplant organs• Discovery of new

medicine/drugs• Cure for diseases

– Cancer

• Skin grafts• Genetic disorders• Injuries and healing

– Spinal

• Cloning

• Ethical/emotional issues– abortion

• Religious beliefs• Fear of cloning• Against human

experimentation• Long term side affects are

unknown and still in progress

• Multipotent• Expensive

HOW COULD STEM CELL RESEARCH BENEFIT OTHER COUNTRIES?Think Globally

Think-Pair-Share

• Think: President Obama recently overturned a ban on federal funds for stem cell research. Should stem cell research be federally funded?

• Are you for or against stem cell research?• Pair: Turn to your neighbor and share your

thoughts

Left-side Activity

• Create a public announcement, newspaper article, flyer, advertisement, t-shirt design ect. Representing your opinion on stem cell research

• Include– What a stem cell is– The two types of stem cells– Where stem cells come from– How they can be used – Illustration