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Aim: What are Prokaryotes ?. Do now: What is the difference between a prokaryotic cell and a eukaryotic cell, and what is more ‘complex’?. http://www.youtube.com/watch?v=u54bRpbSOgs What is called the instructions for life? Are all cells in your body the same? Do cells live forever?.
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Aim: What are Prokaryotes? Do now: What is the difference between a prokaryotic cell and a eukaryotic cell, and what is more ‘complex’?
http://www.youtube.com/watch?v=u54bRpbSOgsWhat is called the instructions for life?Are all cells in your body the same?Do cells live forever?
Prokaryotic • Do not have structures surrounded by membranes • Few internal structures • One-celled organisms, Bacteria http://library.thinkquest.org/C004535/prokaryotic_cells.html
Bacteria features • No nucleus • Flagella or cilia --- extensions of the body that help propel the bacteria around fluid • Some have a cell wall (typically on plant cells) • Free floating DNA – not housed in a nucleus
ProkaryoticBacteria • Good bacteria • Everyone has bacteria that lives within our body: this bacteria helps us digest food • Also good bacteria breaks down nutrients in order to recycle them back into the world • Bad bacteria • Bad bacteria causes disease: these are called pathogenic bacteria
http://www.youtube.com/watch?v=IekdfJ-7Zyk • What do are some of the things good bacteria does to help us survive? • Why is overuse of antiBIOTICS bad?
Good bacteria • Certain bacteria help us digest Bacteroidesbiacutis Why do beans make you gassy?
Bad bacteria – infectious/pathogenic bacterai • Bacillus anthracis -anthrax • Chlamydia trachomatis • Escherichia coli • Salmonella typhi • Streptococcus agalactiae • Yersinia pestis (plague)
Bacteria Can divide quickly and They mutate often • This allows them to adapt quickly • These mutations are only sped up by not having a nucleus – Exposed DNA increases the chance of mutations What does it mean to mutate?
Exit question • Antibiotics fights all bacteria it comes in contact with? Why is bad to take antibiotics all the time?