Biology Predictions/Thoughts (3 Viewers)

Leadmen4y

Well-Known Member
Joined
Feb 26, 2021
Messages
478
Gender
Male
HSC
2021
random segregation occurs in anaphase I only as the second phase of meiosis does not result in any variation, merely the separation of sister chromatids
see https://ib.bioninja.com.au/higher-l...and-evolu/101-meiosis/mendel-and-meiosis.html for more info
i remember having a discussion about this with Hiva on some thread earlier
wait but isn't independent assortment how gametes are unrelatedly sorted to either side of the cell in metaphase I? (becoz I thought after that the chromatids r just pulled to the allocated side rather than randomly segretated) i thought random segregation was how each allele coding for the same trait are segregated which supposedly happens in anaphase II
 

zizi2003_

Well-Known Member
Joined
Dec 18, 2020
Messages
1,471
Gender
Female
HSC
2021
But without random segregation of sister chromatids in anaphase 2 non disjunction will occur. If you get a question regarding the mechanisms of variation in meiosis, I don't think it will be incorrect to say that random segregation occurs in both the first and second division of meiosis.
nondisjunction has nothing to do with randoms segregation tho?? it's basically when a mutation occurs in the gene coding for the microtubules that form spindles, hence the chromatids fail to separate properly. The failure to separate properly has nothing to do with random segregation which is when alleles are randomly distributed into gametes
but ur overall point is right, mutations can absolutely be induced in phase 2 of meiosis and cause variation
but with that logic, mutations also arise during anaphase of mitosis and are hence a source of variation
i wasnt talking about variation in general (including mutations), i was talking about only random segregation as a means of variation that doesnt occur in anaphase II since it's just the separation of sister chromatids just like in mitosis
ED6C4BE7-FE57-4F06-9842-89A4BCA11E72.jpeg
 

zizi2003_

Well-Known Member
Joined
Dec 18, 2020
Messages
1,471
Gender
Female
HSC
2021
wait but isn't independent assortment how gametes are unrelatedly sorted to either side of the cell in metaphase I? (becoz I thought after that the chromatids r just pulled to the allocated side rather than randomly segretated) i thought random segregation was how each allele coding for the same trait are segregated which supposedly happens in anaphase II
wdym by "gametes" are unrelatedly sorted to either side of the cell? yea independent assortment is when homologous chromosomes(maternal and paternal pairs) align in random pairs during metaphase along the metaphase plate
and yes ur definition of random segregation is right except it happens in anaphase I im sure,
 

shadowlike04

Member
Joined
Aug 9, 2021
Messages
29
Gender
Male
HSC
2022
Mechanically, the process of meiosis 2 is similar to mitosis, though its genetic results are fundamentally different. The end result is production of four haploid cells rather than diploid cells.
Chromosome segregation occurs at two separate stages during meiosis called anaphase I and anaphase II - https://en.wikipedia.org/wiki/Chromosome_segregation
Mentioning non-disjunction when talking about random segregation is an error on my part I was trying to illustrate why segregation of chromosomes is essential.
 

Leadmen4y

Well-Known Member
Joined
Feb 26, 2021
Messages
478
Gender
Male
HSC
2021
wdym by "gametes" are unrelatedly sorted to either side of the cell? yea independent assortment is when homologous chromosomes(maternal and paternal pairs) align in random pairs during metaphase along the metaphase plate
and yes ur definition of random segregation is right except it happens in anaphase I im sure,
yeah my bad I meant homologous chromosomes. thanks for the explanation
 

zizi2003_

Well-Known Member
Joined
Dec 18, 2020
Messages
1,471
Gender
Female
HSC
2021
Mechanically, the process of meiosis 2 is similar to mitosis, though its genetic results are fundamentally different. The end result is production of four haploid cells rather than diploid cells.
Mentioning non-disjunction when talking about random segregation is an error on my part I was trying to illustrate why segregation of chromosomes is essential.
yea I wasnt trying to say that meiosis 2 is exactly like mitosis, i was just talking about the mechanics of it- how they both involve the separation of sis chromatids
mhmm but it sure is complicated as to whether random segregation occurs in anaphase 1, 2 or both, since a variety of sources say diff things
but yea I think they would accept it if we say both phases 1 and 2 at this point
 

Leadmen4y

Well-Known Member
Joined
Feb 26, 2021
Messages
478
Gender
Male
HSC
2021
yea I wasnt trying to say that meiosis 2 is exactly like mitosis, i was just talking about the mechanics of it- how they both involve the separation of sis chromatids
mhmm but it sure is complicated as to whether random segregation occurs in anaphase 1, 2 or both, since a variety of sources say diff things
but yea I think they would accept it if we say both phases 1 and 2 at this point
yeah I saw it as anaphase II way back when we were doing mod 5 but I dug the theory n the textbooks all say its anaphase I or doesn't mention it like pearson. i think its confusing since apparently law of segregation and random segregation r different, and chromosome segregation occurs in both anaphase I and II but only I is random. hoping they don't ask meiosis on Monday at this point lol
 

cloud_berry

Well-Known Member
Joined
Jan 11, 2021
Messages
275
Gender
Female
HSC
2021
idk if i redo past trial papers or not, i already did all the practice papers for the new syllabus while studying for trials
 

lily5885

Member
Joined
Nov 3, 2021
Messages
46
Gender
Female
HSC
2021
guys are you going to memorise examples of a genetic disease for each type of mutation like frameshift, chromosomal, etc
 

icycledough

Well-Known Member
Joined
Aug 5, 2021
Messages
784
Gender
Male
HSC
2020
idk if i redo past trial papers or not, i already did all the practice papers for the new syllabus while studying for trials
As biology is in 2 days, it really depends on you whether you want to do past papers, as there are definitely positives and some negatives. Past papers for the sake of it won't be effective, but timed past papers (closed book), marked after and gone through will be much more useful for your study. If you don't want to, then make sure you are doing some sort of active recall study, rather than just 'reading through notes or a textbook', which will prevent you from retaining information. You may want to consolidate your knowledge of weak topics through textbook questions, Youtube/Khan Academy videos, and other resources you have available.
 

lily5885

Member
Joined
Nov 3, 2021
Messages
46
Gender
Female
HSC
2021
reading ur notes is probs the most ineffective study strategy out there, just do some papers lol
i somewhat agree. Reading yournotes is good for a general basis which is what ive been doing but then ive also balanced this with lots and lots of practice papers... not point indoing past papers if you have no idea what youre talking about
 

lily5885

Member
Joined
Nov 3, 2021
Messages
46
Gender
Female
HSC
2021
past hsc questions in order of topics:

Module 5 Heredity - Reproduction

YearQuestions
20202, 3, 25(a-c)
20199, 27(a-b)
2019 Sample1, 11(a-b), 12
201110
Module 5 Heredity - Cell Replication
YearQuestions
202016
20194
2019 Sample2, 13(a-c), 14(a-b)
20184, 29, 33(a)(i)
201713, 17, 19
201610, 13, 26
201523
201229
20114
Module 5 Heredity - DNA and Polypeptide Synthesis
YearQuestions
20205, 20
201914, 33(a)
2019 Sample3, 4, 15
201826(a), 28
201733(c), 34(a)
201511, 14, 34(b)
201432(a), 33(a)
201332(a), 33(b)
20128, 17, 33(b)
201133(b), 34(a)
Module 5 Heredity - Genetic Variation
YearQuestions
202014, 19, 26(a), 26(b)
201911, 17, 28(a), 30, 33(b)(i)
2019 Sample8, 5, 6, 7, 9, 16(a-b), 17
201814, 19, 28, 33(c)(ii)
201712, 15, 24(a-b), 28
20168, 14
20152, 15
201410, 15
20135, 18, 33(a)
201223(b)
20115, 17
Module 5 Heredity - Inheritance Patterns In a Population
YearQuestions
2019 Sample10, 18(a-b)
201734(b), (e)
201433(c)
201333(e)
201134(d), (e)
Module 6 Genetic Change - Mutation
YearQuestions
202017, 18, 23(a-b), 28(b), 29
20193, 13, 15, 22, 25(a-b), 26
2019 Sample1, 2, 3, 4, 8(a-c), 9
201826(b)(i), 33(b)
201734(c)
20164
20141
201225, 33(d)
Module 6 Genetic Change - Biotechnology
YearQuestions
2019 Sample5, 6, 10, 11(a), 12(a)
201832(a)(i), 33(d), 33(e)
201618
201529, 33(a)(i), 33(d)(i)
Module 6 Genetic Change - Genetic Technologies
YearQuestions
202012, 13
20198
2019 Sample7, 10, 11(a-b), 12(b), 13, 14
201810
201731, 33(b)
201633(c)(ii), 33(e)
201416, 33(b)
201330, 33(d)
20121, 33(a)
201133(d)
Module 7 Infectious Disease - Causes of Infectious Disease
YearQuestions
20204, 7, 32(a), 32(b)(i)
201931(a-b)
2019 Sample1, 2, 3, 12, 13
20188, 11, 22, 30
201714
20162, 15, 25
20159
20145, 12, 13
20131, 24, 28(a)
20124, 16
20119, 19, 29
Module 7 Infectious Disease - Responses to Pathogens
YearQuestions
2019 Sample4, 5, 15(a-b)
Module 7 Infectious Disease - Immunity
YearQuestions
20195
2019 Sample6, 7, 8, 16(a-b), 17(a-b)
20183, 16
20174, 6, 11, 30
201611, 19, 20
201517, 19, 20, 27(b)
201417, 21
20132, 4, 6, 21
20123, 13
20118, 14, 16
Module 7 Infectious Disease - Prevention, Treatment and Control
YearQuestions
20206, 15, 21, 22
20192, 10, 32(a-b)
2019 Sample9, 10, 12
201824, 30
201729
201628, 30
201512, 13, 21
201411, 18, 22(a), 23, 25
20133, 7, 11, 28(b)
20126, 7, 27
20117, 24, 26
Module 8 Non-Infectious Disease - Homeostasis
YearQuestions
20201, 31(a-b)
201912, 21, 29
2019 Sample1, 2, 3, 10(a-b)
20189, 21, 26(b)(ii)
20171, 2
201623(b)
20153, 7, 8
20143
201314, 15, 17, 23
201218
20113, 32(a)
Module 8 Non-Infectious Disease - Causes and Effects
YearQuestions
2019 Sample4
201422(b)
20125, 12
Module 8 Non-Infectious Disease - Epidemiology
YearQuestions
20208, 9, 27(a)
201933(b)(ii), 33(c)
2019 Sample5, 6, 11
201516
201223(a), 26
201127
Module 8 Non-Infectious Disease - Prevention
YearQuestions
201923
2019 Sample7
Module 8 Non-Infectious Disease - Technologies and Disorders
YearQuestions
202011, 24(a-c)
20196
2019 Sample8, 9, 13(a-b)
20187, 15, 26(b)(ii), 31(a)(c)(d)
20177, 32(a)(b)(c)(e)
20167, 9, 32(e)
201531, 32(e)
20146, 31(c)
201329, 31(b-d)(e)(ii)
201231(a-b)
201132(c)(e)
 

lily5885

Member
Joined
Nov 3, 2021
Messages
46
Gender
Female
HSC
2021
Questions Covering Multiple Topics
YearQuestionsTopics
202028(a)Mod 5 Cell Replication Mod 5 Genetic Variation
202032(b)(ii)Mod 5 DNA and Polypeptide Synthesis Mod 7 Causes of Infectious Disease
202030Mod 6 Biotechnology Mod 6 Genetic Technologies Mod 7 Prevention, Treatment and Control Mod 8 Prevention
202010Mod 6 Mutation Mod 6 Genetic Technologies
202032(b)(ii)Mod 5 DNA and Polypeptide Synthesis Mod 7 Causes of Infectious Disease
202030Mod 6 Biotechnology Mod 6 Genetic Technologies Mod 7 Prevention, Treatment and Control Mod 8 Prevention
202032(c)Mod 7 Response to Pathogens Mod 7 Immunity Mod 7 Prevention, Treatment and Control
202027(b)Mod 8 Causes and Effects, Mod 8 Epidemiology
2019 Sample Mod 711, 18Mod 7 Causes of Infectious Disease Mod 7 Prevention, Treatment and Control
2019 Sample Mod 714Mod 7 Causes of Infectious Disease Mod 7 Responses to Pathogens
201928(b)Mod 5 Cell Replication Mod 5 Genetic Variation
201918Mod 5 Reproduction Mod 8 Homeostasis
201919, 20, 24Mod 6 Biotechnology Mod 6 Genetic Technologies
20197Mod 7 Causes of Infectious Disease Mod 7 Prevention, Treatment and Control
20191Mod 7 Causes of Infectious Disease, Mod 8 Cause and Effects
201933(d)Mod 7 Causes of Infectious Disease, Mod 8 Causes and Effects, Mod 8 Epidemiology
201916Mod 7 Immunity Mod 7 Prevention, Treatment and Control
201429Mod 5 Reproduction, Mod 5 cell replication
201230Mod 7 Causes of Infectious Disease, Mod 7 Causes of Infectious Disease
201215Mod 8 Homeostasis, Mod 8 Technologies and Disorders
201131Mod 6 Biotechnology, Mod 7 Prevention, Treatment and control, Mod 5 DNA and Polypeptide Synthesis
201125Mod 8 Homeostasis, Mod 8 Technologies and Disorders
 

Leadmen4y

Well-Known Member
Joined
Feb 26, 2021
Messages
478
Gender
Male
HSC
2021
i somewhat agree. Reading yournotes is good for a general basis which is what ive been doing but then ive also balanced this with lots and lots of practice papers... not point indoing past papers if you have no idea what youre talking about
yeah ofc its good to get a general understanding, but doing it more than even once is ineffective imo there are way better ways to memorise stuff like flashcards
 

lily5885

Member
Joined
Nov 3, 2021
Messages
46
Gender
Female
HSC
2021
nondisjunction has nothing to do with randoms segregation tho?? it's basically when a mutation occurs in the gene coding for the microtubules that form spindles, hence the chromatids fail to separate properly. The failure to separate properly has nothing to do with random segregation which is when alleles are randomly distributed into gametes
but ur overall point is right, mutations can absolutely be induced in phase 2 of meiosis and cause variation
but with that logic, mutations also arise during anaphase of mitosis and are hence a source of variation
i wasnt talking about variation in general (including mutations), i was talking about only random segregation as a means of variation that doesnt occur in anaphase II since it's just the separation of sister chromatids just like in mitosis
View attachment 33922
thanksso much forthis,really helpedme !
 

Users Who Are Viewing This Thread (Users: 0, Guests: 3)

Top