HSC Biology. Year 2014 Mark Pages 21 Published Jan 12, Biology: Option Genetics: The Code Broken. By Leah (97.7 ATAR)

Transcription

1 HSC Bilgy Year 2014 Mark Pages 21 Published Jan 12, 2017 Bilgy: Optin Genetics: The Cde Brken. By Leah (97.7 ATAR)

2 Pwered by TCPDF ( Yur ntes authr, Leah. Leah achieved an ATAR f 97.7 in 2014 while attending Tara Anglican Schl Fr Girls Currently studying Bachelr f Primary Educatin at The University f Sydney Achievements: 2nd in State HSC Gegraphy 2014 Caltex All Runder Award 2014 Gegraphy Teacher's Assciatin Arthur Phillip Award 2011 and 2012 Band 6 HSC Bilgy Band 6 HSC General Mathematics Band 6 HSC Gegraphy (mark f 97) Band 6 HSC Fd Technlgy Band 6 Studies f Religin I Leah says: Hi all, I achieved an ATAR f 97.7 in the 2014 HSC ranking 2nd in the State in Gegraphy. I'm currently studying a Bachelr f Primary Educatin at the University f Sydney and am super passinate abut educating yung peple t achieve incredible things. I have ver 2 years f tutring experience and my ntes cmprehensively cver all HSC syllabus dt pints. My advice is wrk hard and play hard- after all, this is yur last year f schl! Enjy yur last sprts carnivals, muck up days and all the extra curricular activities yu d whilst studying diligently and thrughly t enjy the all imprtant balance f year 12.

3 GENETICS THE CODE BROKEN HSC BIOLOGY NOTES Transfer f infrmatin frm DNA thrugh RNA t prduce a sequence f amin acids in a plypeptide- DNA RNA Nucletides- single base, sugar, phsphate Wund t frm duble helix In chrmsmes f eukarytic (membrane bund) rganisms- DNA is wrapped arund prteins called histnes Gene begins with a nn-cding sequence called a prmted, ends with a terminatr Genes cntain exns (cding) and nn-cding sequences called intrns Cndensatin- DNA wraps int a tight spiral- cils and flds many times during replicatin preparatin mrna (messenger RNA), trna (transfer RNA), rrna (ribsmal RNA) RNA structure- single stranded, ribse sugar, Uracil instead f thymine, nly a few thusands bases lng trna- clver shape, anti-cdn n ne end, accepting end hlds amin acid nn-cding strand cdes fr a prtein intrns are transcribed with exns then later intrns are cut ut because mrna is s lng, several ribsmes can attach t it, making several plypeptides at the same time Functin Ribsme- site f prtein synthesis trna- carries amin acid t ribsme DNA- carries genetic infrmatin, prvides a template fr plypeptide synthesis 1.a Cnstruct a DNA mdel- Dexyribnucleic sugar and phsphate backbne Cmplementary bases- Adenine& thymine, guanine& cytsine Nucletide- ne sugar, phsphate, nitrgenus base Duble helix- spiral Phsphate smaller than sugar

4 GENETICS THE CODE BROKEN HSC BIOLOGY NOTES 2 1.b Outline the current understanding f gene expressin- Gene expressin- refers t a gene being turned n t prduce a plypeptide which then shws the trait phentypically 1. Unpacking the chrmsme DNA wund arund histnes, DNA must be unpacked in the regin f the chrmsme t be read 2. Turning n the gene An enhancer must bind t a prmter fr gene expressin t ccur Prmtr (marker)- shrt regulatry area at the start f a gene, acts as a binding site (TATA bx- adenine and thymine) Enhancer (marker)- shrt regin f DNA that is far away frm the gene they influence- when in cntact with prmtr, increase the rate f transcriptin Transcriptin factrs (regulatry prteins) bring enhancers t prmtrs and bind them- this marker signals RNA plymerase t bind and start transcriptin in PCR plymerase chain reactin 3. Transcriptin in the nucleus 4. RNA prcessing (spicing f intrns, capping and tailing) mrna is made f 80% nn-cding junk DNA called intrns mrna needs t be mdified befre leaving the nucleus intrns remved by RNA splicing (restrictin enzyme cuts and leaves sticky endsligase enzyme pastes ) mrna receives a cap and tail (cnsisting f several bases) t prevent mlecule frm being degraded mrna is used thusands f times at ribsmes befre it is recycled 5. Translatin At ribsme in cytplasm t prduce plypeptide 6. Prtein Mdificatin Prteins assembled by cutting, flding and crss linking plypeptides t frm a specific #D prtein Jined and flded depending n functin 2.1 Characteristics determined by multiple alleles- Multiple alleles Invlves ne gene- but many alleles exist 2 r mre alleles cntrl 1 characteristic (hwever each individual can nly have a maximum f 2 alleles) Gives rise t discrete characteristics Fund n the same lcus n hmlgus chrmsmes

5 Pwered by TCPDF ( GENETICS THE CODE BROKEN HSC BIOLOGY NOTES 3 E.g. in human bld types- I A antigen A, I B antigen B, I n antigens E.g. in drsphilia melangaster (fruit fly)- w + red eyes, w a aprict eyes, w h hney eyes, w p pearl eyes, w i ivry eyes, w white eyes E.g. fur clur in rabbits- C intense black, c ch chinchilla (white fur, black tips), c h Himalayan (black eyes, nse, feet), c albin 2.2 Inheritance f ABO and Rhesus bld grups- If transfusin are given t thse wh are nt bld type cmpatible- agglutinatin- immune system attaches t cells and cause them t clump Bld Types ABO A (I a, I a )- a antigen, b antibdies B (I b, I b )- b antigen, a antibdies AB (I a,i b )- bth antigens, n antibdies O (I,i)- n antigens, a and b antibdies A and B c-dminant (tw alleles expressed heterzygus), O recessive Bld O universal dnr - bld can be given t anyne Bld AB universal recipient - accept any bld Bld grups can be used in paternity tests t determine wh is nt the father (nt definitive n wh is the father) Rhesus factr is an extra antigen n bld cells- nt a prblem with transfusins but is a prblem with difficult pregnancies Rh negative- recessive- prduce antibdies (Rh- dd) Rh psitive- dminant- n antibdies (Rh+ Dd r DD) If mum is Rh-, and baby is Rh+, in prblem pregnancies, mums immune system prduces antibdies and memry cells. If 2 nd pregnancy difficult, blds mix, mums antibdies cause agglutinatin in baby and destry fetal cells 2.a Predict the inheritance patterns f ABO bld grups and Rhesus factr-