CELLS

MITOSIS

TISSUE

CANCER

What do the following organisms have in common?

skink Conch

deer

starfish

salamander

They have body parts that can….. REGROW!

Humans have limited abilities to regrow body parts….

A healthy liver can

regenerate … that’s why you

can be a living donor and

donate a portion of your liver

to someone with a diseased

one

But now – medical breakthroughs in regenerative medicine has led to this….

PlanariaLaboratory Investigation

Learning Goal…..

To become familiar with Planaria (flatworms) and why they are important organisms in regenerative medicine

What are Planaria?

flatworms Most live in freshwater Avoid light (“negative

phototaxis”) Free living – not parasites Carnivores – eat decaying

meat, insects and larvae (egg yolks or liver in the lab)

1-20 mm in size Exhibit bilateral symmetry

This picture has been released it into the public domain.

Single opening (mouth/anus) – the Pharynx (feeding tube)

-branched intestines- to distribute nutrients to all cells

Digestive System Nervous system

- Can detect temperature changes, light, touch and chemicals in its environment. What type of tissue would help it do these things?

Movement You will notice that a

Planarian can twist, turn, stretch and contract (shorten) its body - What type of tissue would permit such movement?

You may also notice your worm “gliding” across the water. This is because they have CILIA on their ventral surface that “sweep” them along.

These simple flatworms are easily damaged, but …….

Planaria have an amazing ability to regenerate parts of themselves – into a complete flatworm

They make excellent organisms to study because they regrow fairly quickly and easily in a lab environment

By studying planarian regeneration, scientists can learn more about the complexity of tissue regeneration 1/279th

What type of cells do Planaria have to allow them to re-grow and form any type of cell it

needed?

Slide courtesy of Dr. Sánchez Alvarado and Dr. Kyle Gurley

Learning Goal……• To establish the variables for

our investigation of tissue regeneration in Planaria

Our Laboratory Investigation-

The effect of ___________on the amount of tissue regrowth in severed planaria

Group Discussion:What variables might affect how much a

flatworm can regrow in a 2 week period?

Record your ideas on the sticky note paper

provided. One variable per sticky note.

Group 1 Group 2 Group 3

Yoanna Cole Austin

Brandon Justina Joyal

Supriya Mallika Bianca

Nisarg Anjila Monashi

Sonia Candice

Group 4 Group 5 Group 6

Yordel Priyanka Sneh

Dennishia Shadavia Surbi

Manjot Namita Ramlah

Ocean Ranjeet Impreet

For Our Investigation …..

The Independent Variable will be the effect of a specific vitamin

What vitamin?

Answer…

Vitamin DWhat is it?- A vitamin produced naturally in our body in

response to UV radiation from sunlight.- Added to foods – like eggs and milk - to increase intake

Headlines….

Vitamin D deficiency common in cancer patients - Medical Xpressmedicalxpress.com/.../2011-10-vitamin-d-deficiency-common-cance...Cached

3 Oct 2011 – More than three-quarters of cancer patients have insufficient levels of ... of patients had vitamin D concentrations either deficient (less than 20 ...

Skin Cancer Patients More Likely to Be Deficient in Vit D - - TIME ...healthland.time.com/.../balancing-skin-cancer-risk-and-low-vitamin-...Cached - Similar

19 Oct 2010 – It's a health conundrum that doctors have been trying to resolve for several years now: most Americans are deficient in vitamin D, which can ...

Cancer and diabetes patients trend toward vitamin D deficiency ...www.themedifastplan.com/.../cancer-and-diabetes-patien... - United StatesCached

10 Oct 2011 – Sunlight is the recognized as the best natural source of vitamin D, but ... The vitamin D deficient cancer patients were put on a regimen of ...

Vitamin D deficiency tied to host of dangers - The Boston Globewww.boston.com › News › Boston Globe › Health / ScienceSimilar

30 Dec 2004 – ... deficiency of vitamin D among Americans is more harmful than once ... increasing their risk of fractures, muscle weakness, and even cancer

Our Investigation

Purpose: How does Vitamin D (independent variable) affect the amount of tissue regeneration (dependent variable) that occurs in a 2 week period?

What variables would we have to keep constant to

make this a scientifically valid experiment?

Record your answers on sticky notes of a

different colour than the first task

What do you notice about the list of all the

possible independent variables and the list of

constant variables you just came up with?

Making Observations…

Select one or two worms from the container and do the following:

- Observe how it swims- flip it over, does it flip back on its own- Shine a light on it – what does it do?- Sketch it

In closing……

William Wallace – a 13th century Scottish man who led his people to fight for Scotland’s independence from England

BABattle cry:

FREEDOM!

?RIDDLE

If Planaria were to take over the world, what would be their battle cry?

http://www.cheeksofgod.com/planarian-man/

Care for your Planaria. Then what?

Your group will make observations on Monday, Wednesday and Friday for two weeks

You will measure the severed sections and determine the length of time (in days) required for the planarian to regenerate

You will record your results in your handouts You will determine if vitamin D has an effect

on regeneration

Slide courtesy of Dr. Sánchez Alvarado and Dr. Kyle Gurley