Image from: http://biologytb. net23. net/text/chapter27/27images/27-02 Cells & Tissues (3.1)

Cells There are 75 to 100 trillion cells in the human body. Most cells are specialized to perform specific roles. What causes them to differentiate? Image: http://i1-news.softpedia-static.com/images/news2/Cooperative-Behavior-Increases-Cellular-Mobility-2.jpg

Cell Specialization Factors that affect cell specialization: cell cytoplasm environmental conditions neighbouring cells Image: http://kmbiology.weebly.com/uploads/6/0/1/1/6011704/5007385.jpg?491

Abnormal Development Environmental factors such as exposure to chemicals can cause abnormal cell specialization & development. Image: http://pubs.usgs.gov/fs/fs-043-01/images/fig3.jpg

Turning on/off genes When cells are specialized, they have certain genes “turned off” and others “turned on”. Image: http://www.mentalhealthy.co.uk/sites/default/files/Depositphotos_4925217_XS.jpg

Specialized animal cells are organized into tissues, just like plant cells.

Types of Tissues Image: http://www.wonderwhizkids.com/resources/content/imagesv4/biology/concept/basic_principle/Animal_Tissues.gif

Epithelial Tissue Strongly connected cells form barriers that line the surfaces of the body. e.g., skin epithelia, columnar epithelia (line the digestive tract & glands) Image: http://web.clark.edu/rrausch/biolabs/histo/epithelia/PCCE_100.jpg

Muscle Tissue Changes shape by shortening & lengthening. e.g., skeletal muscle, smooth muscle, cardiac muscle Image: http://sciencelearn.org.nz/var/sciencelearn/storage/images/contexts/sporting-edge/science-ideas-and-concepts/muscle-structure-muscle-under-the-microscope/9302-34-eng-NZ/Muscle-structure-muscle-under-the-microscope.jpg

Nervous Tissue coordinates body actions using cells called neurons moves information between brain/spinal cord to muscles/glands & detects environmental information Image: https://o.quizlet.com/i/8hCwUBKPV_6OwDITTWmQQw_m.jpg

Connective Tissue strengthens, supports, protects, and connects cells & tissues e.g., bone, fat, blood Image: http://www.quia.com/files/quia/users/lmcgee/Systems/9AP_Chapter_40_AnimalForm_and_Function/Connective_Tissue_Types.jpg

Image: https://rhvillegas. files. wordpress

Organ Donation According to the Trillium Gift of Life Network, there are approximately 1600 Ontarians on transplant waiting lists. Image: http://financialtribune.com/sites/default/files/field/image/12_Transplant%20(3).jpg

Organs for Transplant Image: http://s.hswstatic.com/gif/organ-transplant-statistic2.gif

Living Donation Living donation accounted for 255 transplants in Ontario in 2012. Because of the long wait lists, sometimes people look for donors on social media, or turn to illegal organ trade themselves… Image: http://yourblackworld.net/wp-content/uploads/2012/06/01/kidney.jpg