Biology Unit 4 Questions Megathread

[Russ]

You're both right and wrong.
Sperm have practically no cytoplasm and, as such, practically no organelles. The secondary oocyte/egg has a lot of cytoplasm and thus a lot of organelles. That's why mitochondrial DNA is such a good marker of maternal lineage.

However, when it comes to proteins involved in structure of organelles, they're obviously determined by both maternal and paternal alleles via Mendelian inheritance.

[Zebra]

If there was reproductive isolation (ie blue birds refused to mate with red birds) in a population that lived in the same area , would this confer sympatric speciation (formation of two or more descendant species from a single ancestor all occuping the same geographical location)?

don't tell me i have to learn what a sympatric speciation is...

[nooshnoosh95]

If there was reproductive isolation (ie blue birds refused to mate with red birds) in a population that lived in the same area , would this confer sympatric speciation (formation of two or more descendant species from a single ancestor all occuping the same geographical location)?

don't tell me i have to learn what a sympatric speciation is...

all we were taught was sympatric is variation that occurs without physical isolation and allopatric is speciation that results when a population is divided by a physical barrier (geographic isolation)
so i guess you wouldnt need to know much detail, because that was everything we learnt about allopatric and sympatric

[WhoTookMyUsername]

yeah it won't hurt to know it but its hugely unlikely there will be any marks on the exam on it. VCAA feels it just complicates things up too much and like to go by the principle that speciation is due to geographic barriers

[Kaille]

does mendel's first law (principle of segregation) result in variation in the gametes?

[lexitu]

Second law mainly - independent assortment If alleles of genes that are not linked can be assort in different combinations then gametes will be almost infinitely varied. Of course, alleles have to segregate for this to happen in the first place, but it's the independent assortment, as well as crossing over that results in variation.

[Kaille]

ohh i see thanks

[WhoTookMyUsername]

Is coexistence conclusive proof that neither species was the ancestor of the other?

Sources seem to say it is,
but couldn't evolution occur where one species is split into two populations, one diverges into new species and the other stays the same (what is this speciation called? NOB says branching but that doesn't... sound right?)

and then they reintegrate and coexist?

[Kaille]

are block mutations in the bio course? i haven't seen much of it my textbook.....

[Kaille]

would i be awarded the mark if i said "the amount of males and females affected are equal" (in reference to providing evidence of an autosomal pedigree)?

[lexitu]

would i be awarded the mark if i said "the amount of males and females affected are equal" (in reference to providing evidence of an autosomal pedigree)?

Depends what the question is, but probably not, because the sample you are using is too small for that to be useful. It's better to say why it's not the alternative and why it is the type of inheritance that it is with relation to people in the pedigree.

[WhoTookMyUsername]

Is coexistence conclusive proof that neither species was the ancestor of the other?

Sources seem to say it is,
but couldn't evolution occur where one species is split into two populations, one diverges into new species and the other stays the same (what is this speciation called? NOB says branching but that doesn't... sound right?)

and then they reintegrate and coexist?

[scar]

are block mutations in the bio course? i haven't seen much of it my textbook.....

Yes definitely!!!   Look at VCAA 2008  Short Answer Q4.  Major marks all mased around the idea of block mutations!!

[WhoTookMyUsername]

(sorry to repost but questions seem to always get lost when others are asked after on previous pages
Is coexistence conclusive proof that neither species was the ancestor of the other?

Sources seem to say it is,
but couldn't evolution occur where one species is split into two populations, one diverges into new species and the other stays the same (what is this speciation called? NOB says branching but that doesn't... sound right?)

and then they reintegrate and coexist?

also:
q) what are the names of eukaryotic organisms that contain DNA from other species?

this was on a prac exam

i said "transfected"
most of my friends said transgenic
,
i thought transfected was more accurate as transgenic can refer to prokaryotes as well..

also

what is the best defintion for transcription?
i've seen so many but yet to see one i really like

[omgwtf123]

q) what are the names of eukaryotic organisms that contain DNA from other species? Isn't that transgenic organisms, because prokaryotes that contain DNA from other species areknown as "transformed" organisms. I may be wrong, but hope this helps