Lysosomes and Peroxisomes

Lysosomes and Peroxisomes

By: Heather R, Chelsie W. and Cullen M.

Lysosomes and Peroxisomes• Lysosomes and Peroxisomes are both

found in the cytoplasm in some cells. Lysosomes are found in eukaryotic animal cells and rarely in plant cells. Peroxisomes are found in both, but in far greater numbers in eukaryotic cells.

Peroxisomes

• Peroxisomes are organelles found in the cytoplasm, they are some of the first organelles to develop in cells. They are responsible for removing toxins from the cell and especially hydrogen peroxide, which is a natural by-product of cell metabolism.

DescriptionPeroxisomes: diameters of about 0.5 micron

Postage Stamp (1 inch) -> 25 400Eye of a needle ->1230Table Salt -> 120Spider web (individual strand) -> 2-3Millimeter- 0.001

*Round or oval bodies-chiton-mollusc-Hepatopancreas organ

In depth look at Peroxisomes

• Unlike mitochondria they cannot replicate using there own DNA and they must be created from DNA stored in the nucleus. Once created they wait for an particular amino acid signal, called a peroxiosomal targeting signal to hit the receptors to begin its job.

Associated Problems • The Peroxisomes are associated with

metabolic diseases, approximately 1 in every 20 000 people suffer from a mutation of a Peroxisomes, or lack of them. There are some nasty disease associated with it especially Zellwegar’s disease in new-borns, most will die before the age of one.

Lysosomes• The job of a lysosome contains

certain hydrolytic enzymes used for digestion. The lysosome will bond with particlues brought into the cell by phagocytosis. The lysosome will release its contents into the membrane of the foreign particle. These enzymes will break down and digest the particle.

Description cont...Lysosomes:

“

• suicide-bags• Lysis- dissolution or

destruction• Tiny, smaller than

vacuoles• Found in tears and

saliva• 200nm - 500nm• Kiss and Run!

In depth look at Lysosomes• The enzymes called hydrolases are

created in the cells endoplasmic reticulum. They are then transported to the golgi apparatus where the lysosome is created and released into the cytoplasm of the cell. The lysosome will bond to either a phagosome or a defective or worn out organelle. It will inject the hydrolases into the membrane.

Associated Problems• If certain hydrolases are missing from

a cell, serious illness can occur due to a build up of molecules and organelles.

Apoptosis• Programmed cell death• No harmful substances into area• Health of body• Immortal (cancer)• Works too well-> kills too many cells->tissue

damage (strokes & Parkinson's)

• http://highered.mcgraw-hill.com/sites/0072495855/student_view0/chapter2/animation__lysosomes.html