RegenerationRegeneration Is the ability to regrow a Is the ability to regrow a tissue, an organ or a tissue, an organ or a part of the bodypart of the body

Humans can regenerate: Humans can regenerate: blood, bone, skinblood, bone, skin

Animals that Animals that RegenerateRegenerate

What animals can What animals can regenerate?regenerate?

Many animals can Many animals can grow new parts of grow new parts of their bodies to their bodies to replace those that replace those that have been have been damageddamaged

LIZARDS--> tailLIZARDS--> tail

Animals that Animals that RegenerateRegenerate

Planarians-->Planarians-->if cut into pieces, each if cut into pieces, each piece will grow into a new worm (p.186) piece will grow into a new worm (p.186)

Sea CucumbersSea Cucumbers--> body is three feet --> body is three feet long. If cut, can grow new sea cucumberlong. If cut, can grow new sea cucumber

Sharks-->Sharks-->continually replace lost teethcontinually replace lost teeth SpidersSpiders--> regrow missing legs or parts --> regrow missing legs or parts

of legsof legs SpongesSponges--> can be divided, and will --> can be divided, and will

regrow to be exactly as before.regrow to be exactly as before.

Animals that Animals that RegenerateRegenerate

StarfishStarfish--> --> that lose arms that lose arms can grow new can grow new onesones

Sometimes an Sometimes an entire animal entire animal can regrow can regrow from a lost armfrom a lost arm

FragmentationFragmentation

A form of asexual A form of asexual reproduction where a new reproduction where a new organism is formed from a organism is formed from a part that breaks off from part that breaks off from the parentthe parent

ie. Sponge, planarianie. Sponge, planarian

Cell SpecializationCell Specialization

The nucleus of every cell contains a The nucleus of every cell contains a complete code for your characteristics.complete code for your characteristics.

(Every cell contains identical DNA)(Every cell contains identical DNA) Why can skin cells regenerate when Why can skin cells regenerate when

nerve cells can’t?nerve cells can’t? Because each cell uses only a specific Because each cell uses only a specific

part of their DNA. part of their DNA. Ie. The muscle producing part of DNA is Ie. The muscle producing part of DNA is

turned off in nerve cellsturned off in nerve cells

Cell Specialization Cell Specialization cont’dcont’d

Animals with little cell specialization Animals with little cell specialization are capable of regenerationare capable of regeneration

The cells of these organisms are The cells of these organisms are very similarvery similar

Complex animals (like dogs, Complex animals (like dogs, elephants etc.) have more cell elephants etc.) have more cell specialization (where specific parts specialization (where specific parts of the DNA are turned off)of the DNA are turned off)

Producing Plants Producing Plants without Seedswithout Seeds

What happens to a potato when it What happens to a potato when it has been left for a while?has been left for a while?

It grows eyes (tiny buds)It grows eyes (tiny buds)

see p.190see p.190

PotatoesPotatoes

So, when farmers grow potato So, when farmers grow potato crops, they make sure a section of crops, they make sure a section of the potato containing an eye is the potato containing an eye is plantedplanted

Using a potato eye to grow a new Using a potato eye to grow a new potato is a type of asexual potato is a type of asexual reproductionreproduction

What are some other examples of What are some other examples of growing a new plant from another growing a new plant from another plant?plant?

ie. Spider plantie. Spider plant

FactFact

When a new plant that has been When a new plant that has been grown from an already existing grown from an already existing plant, is the new plant is plant, is the new plant is genetically identical to the parent?genetically identical to the parent?

Yes!Yes!

DollyDolly

DollyDolly