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=The rest of the term:= Wednesday: Finish Outcome 7-you must have completed your work on cloning-see questions at the bottom of this page. We will also look at your wikipages on selective breeding. HGP homework now overdue. Thursday: Start Outcome 8 Friday: Continue Outcome 8 Monday: Conclude GCB Tuesday: Revision/Work on famous female and male scientist.Elizabeth Blackburn? Ian Frazer Wednesday: Looking at the H's. Is this our last lesson-party time!!!!!

=Biodiversity= http://vimeo.com/14105623 (short) =26th August= Don't forget to look in the Genetics The Code Broken section of the wiki. In particular, click on websites for some good resources. =A bit of fun... [|the giant squid dissection]=

=6th August= Mutations: =http://www.abc.net.au/science/articles/2010/08/05/2973348.htm= =Discussion posts are the place to ask your questions.= Start a new post for a new topic area or question?? Might make it less confusing. Up to you. =Question: if all the females eggs are produced prior to birth, how does maternal age affect Down's syndrome and non disjunction?= Maternal age and meiosis-interest only

WHAT IS A "TRUE EGG"?

“Eggs” are produced in the ovaries, BUT these are not "true eggs" yet, and will never complete meiosis (a special type of cell division) and become "true eggs" unless OR until they are first fertilized by a sperm. Within the ovary, a follicle consists of one potential egg cell surrounded by special cells to nourish and protect it.

HOW MANY EGGS DOES A WOMAN ACTUALLY HAVE?

A human female typically has about 400,000 follicles/potential eggs, all formed before birth. Only several hundred (about 480) of these “eggs” will actually ever be released during her reproductive years. Normally, in humans, after the onset of puberty, due to the stimulation of follicular-stimulating-hormone (FSH) one “egg” per cycle matures and is released from its ovary. One month the left ovary will release a potential egg and the next month the right ovary will release a potential egg.

Its a start and has given me more questions to ask and answer!!!

and more.... Of the 7 million potential oocytes that form during the 5th month of female embryo development, 99.9% will be eliminated prior to being ovulated and these are resorbed by the body. Potential oocytes remain in a latency phase until hormones released at puberty result in oocytes going through meiosis I and being ripened individually and released on a monthly basis. At the end of meiosis, females have two daughter cells and meiosis II only occurs if and when fertilization occurs by a sperm cell. At that time both daughter cells divide to form 4 cells and of the 4 cells formed, 3 are discarded. An egg cell that is not fertilized is ovulated as a pair of daughter cells which are ultimately discarded at menstruation are not "finished" eggs. They have not undergone meiosis II. Without fertilization by a sperm making its way to the fallopian tube, meiosis II will not occur and the spent egg released will have two identical daughter cells.

So-I think I get it. =A GREAT RESOURCE **This website has podcasts of ALL the HSC outcomes-download and listen while you are walking, eating, sleeping......... [] Welcome to Year 12 Biology:**=

[|**http://www.hhmi.org/biointeractive/dna/animations.html**]

**You might like to look at this site which has a lot of [|Biology video clips]as part of your revision.**
**14th June** (LH) Use the links on the toolbar to find information on your core topics and option.

I will add general links to this page:

http://www.learner.org/courses/biology/archive/animations.html

Good for immune response http://www.learner.org/courses/biology/archive/animations/hires/a_hiv1_h.html

Have a look at some videos from ABC Catalyst http://www.abc.net.au/tv/geo/catalyst/vodcast/default.htm

15th June (LH) We can start using this page to communicate as a blog. I have Code Broken context and you will get the syllabus at the end of the week. The first outcome deals with protein synthesis and DNA replication so make sure this is just revision as we will move quickly through this.

16th June []

25th June Transforming medicine in the genome age http://news.bbc.co.uk/2/hi/science_and_environment/10388183.stm

LH 25.6 I am inviting Ms Halletts class to join

25/06/10 Georgia McCarthy - just joined Wiki! Looking forward to looking around the site.

26/06/10 Helen Pope - joined :)

26th June (JH) Happy holidays everyone! Thanks Ms Herbert for inviting our class to join the wiki on Friday. Great CysticFibrosis site in websites CB.

27th June Rebecca Hill-Scott just joined!!

30th June Chelsea Witham joined :D gotta love bio.

4th July LH-back from Port Douglas-loved the Daintree rainforest-the oldest in the world-floated on boat past crocodiles and red mangroves-solve their problem of estuarine environment by collecting salt in their leaves, which then turn yellow and fall off. Was I the only one excited by this???? probably.