Understanding through Discussion


Welcome! You are not logged in. [ Login ]
EvC Forum active members: 86 (8943 total)
22 online now:
ringo, Thugpreacha (AdminPhat) (2 members, 20 visitors)
Newest Member: LaLa dawn
Post Volume: Total: 863,988 Year: 19,024/19,786 Month: 1,444/1,705 Week: 250/446 Day: 48/98 Hour: 1/2


Thread  Details

Email This Thread
Newer Topic | Older Topic
  
Author Topic:   Evolution Simplified
kuresu
Member (Idle past 804 days)
Posts: 2544
From: boulder, colorado
Joined: 03-24-2006


Message 136 of 170 (311485)
05-12-2006 4:31 PM
Reply to: Message 135 by robinrohan
05-12-2006 4:29 PM


Re: Heritable traits
Unless for some reason all the offspring were born homozygous dominant in the example we've been using, the answer is yes.

This message is a reply to:
 Message 135 by robinrohan, posted 05-12-2006 4:29 PM robinrohan has responded

Replies to this message:
 Message 140 by robinrohan, posted 05-12-2006 5:06 PM kuresu has responded

    
kuresu
Member (Idle past 804 days)
Posts: 2544
From: boulder, colorado
Joined: 03-24-2006


Message 137 of 170 (311486)
05-12-2006 4:37 PM
Reply to: Message 133 by robinrohan
05-12-2006 4:15 PM


Re: Clarifying sexual recombination
any mutations that have evolutionary significance occur during conception

conception, if I remeber correclty, is the process of sperm and egg meeting and combining their genetic material. mutations do happen here, but EZscience wasn't talking about those. However, these mutations do have "evolutionary significance".

you may have misunderstood EZscience when he said:

the odds are that we all carry a number of mutations that occurred during the formation of the gametes that gave rise to us when they formed a zygote

he mentioned the mutations that happen during gametic formation. These are the ones that happen while you body is making sperm or eggs (depending on your sex). The mutations from this process are the ones passed on, because gametes, not body cells, are used to form zygotes. These, then, have "evolutionary significance".

Keep in mind, if something is capable of budding (like hydra), or growing from clippings (like many plants) this isn't always the case.


This message is a reply to:
 Message 133 by robinrohan, posted 05-12-2006 4:15 PM robinrohan has responded

Replies to this message:
 Message 139 by robinrohan, posted 05-12-2006 5:01 PM kuresu has not yet responded

    
EZscience
Member (Idle past 3445 days)
Posts: 961
From: A wheatfield in Kansas
Joined: 04-14-2005


Message 138 of 170 (311487)
05-12-2006 4:37 PM
Reply to: Message 133 by robinrohan
05-12-2006 4:15 PM


Mutations
They (AbE *heritable* mutations) can occur at any time in the development of a germ cell line(the cells giving rise to sperm and eggs), but they are most likely to occur during a cell division because this is when all the genes are copied. Any other type of mutation is termed a 'somatic' mutation and is not heritable (as kuresu correctly notes).

This message has been edited by EZscience, 05-12-2006 03:41 PM


This message is a reply to:
 Message 133 by robinrohan, posted 05-12-2006 4:15 PM robinrohan has not yet responded

  
robinrohan
Inactive Member


Message 139 of 170 (311490)
05-12-2006 5:01 PM
Reply to: Message 137 by kuresu
05-12-2006 4:37 PM


Re: Clarifying sexual recombination
These are the ones that happen while you body is making sperm or eggs (depending on your sex).

OK, I got it now. You're right; I didn't understand what EZscience was saying. It's confusing. There seem to be so many different types of mutation.

This message has been edited by robinrohan, 05-12-2006 04:01 PM


This message is a reply to:
 Message 137 by kuresu, posted 05-12-2006 4:37 PM kuresu has not yet responded

  
robinrohan
Inactive Member


Message 140 of 170 (311492)
05-12-2006 5:06 PM
Reply to: Message 136 by kuresu
05-12-2006 4:31 PM


Re: Heritable traits
Unless for some reason all the offspring were born homozygous dominant in the example we've been using, the answer is yes.

OK, then it's not an absolute. It's possible, though perhaps unlikely, that a positive trait would appear and not be passed down.

So what you need is not only this appearance of a positive trait but also that individual has to mate with the right partner. Otherwise evolution will not occur.


This message is a reply to:
 Message 136 by kuresu, posted 05-12-2006 4:31 PM kuresu has responded

Replies to this message:
 Message 141 by kuresu, posted 05-12-2006 5:14 PM robinrohan has responded
 Message 147 by kuresu, posted 05-12-2006 5:38 PM robinrohan has responded

  
kuresu
Member (Idle past 804 days)
Posts: 2544
From: boulder, colorado
Joined: 03-24-2006


Message 141 of 170 (311493)
05-12-2006 5:14 PM
Reply to: Message 140 by robinrohan
05-12-2006 5:06 PM


Re: Heritable traits
you may be taking my comment a bit out of context, or something like that. We have assumed that blue eyes are reccesive in the example. in order for it to be expressed, the person must be "bb". However, it could be that the person is "Bb", in which case he still carries the gene. a right partner isn't needed, unless you mean someone of the opposite sex in your species (for mating, sexes are required). The person carrying the gene just has to mate in order to pass it down, barring the unlikely scenario that you quoted that I gave.

This message is a reply to:
 Message 140 by robinrohan, posted 05-12-2006 5:06 PM robinrohan has responded

Replies to this message:
 Message 142 by robinrohan, posted 05-12-2006 5:18 PM kuresu has responded

    
robinrohan
Inactive Member


Message 142 of 170 (311497)
05-12-2006 5:18 PM
Reply to: Message 141 by kuresu
05-12-2006 5:14 PM


Re: Heritable traits
The person carrying the gene just has to mate in order to pass it down, barring the unlikely scenario that you quoted that I gave.

Just the fact that the unlikely scenario is possible means the process is not absolute. However unlikely, it might not happen.


This message is a reply to:
 Message 141 by kuresu, posted 05-12-2006 5:14 PM kuresu has responded

Replies to this message:
 Message 143 by kuresu, posted 05-12-2006 5:23 PM robinrohan has responded

  
kuresu
Member (Idle past 804 days)
Posts: 2544
From: boulder, colorado
Joined: 03-24-2006


Message 143 of 170 (311500)
05-12-2006 5:23 PM
Reply to: Message 142 by robinrohan
05-12-2006 5:18 PM


Re: Heritable traits
I think my post was more to dispel the need for the "right partner" in order to pass on the gene. That wasn't quite clear in my last post.

let me try again. the right partner is not needed in order to pass on the gene, that person just has to mate.


This message is a reply to:
 Message 142 by robinrohan, posted 05-12-2006 5:18 PM robinrohan has responded

Replies to this message:
 Message 144 by robinrohan, posted 05-12-2006 5:25 PM kuresu has responded

    
robinrohan
Inactive Member


Message 144 of 170 (311502)
05-12-2006 5:25 PM
Reply to: Message 143 by kuresu
05-12-2006 5:23 PM


Re: Heritable traits
the right partner is not needed in order to pass on the gene, that person just has to mate.

OK, so being born homozygous dominant has nothing to do with the parents.


This message is a reply to:
 Message 143 by kuresu, posted 05-12-2006 5:23 PM kuresu has responded

Replies to this message:
 Message 145 by kuresu, posted 05-12-2006 5:31 PM robinrohan has responded

  
kuresu
Member (Idle past 804 days)
Posts: 2544
From: boulder, colorado
Joined: 03-24-2006


Message 145 of 170 (311506)
05-12-2006 5:31 PM
Reply to: Message 144 by robinrohan
05-12-2006 5:25 PM


Re: Heritable traits
it has everything to do with the parents. my objection was when you said that in order to pass on the gene the person with it needed to mate with the "right person". Which is why I said that the person carrying the blue eye gene just needed to mate in order to pass it on.

This message is a reply to:
 Message 144 by robinrohan, posted 05-12-2006 5:25 PM robinrohan has responded

Replies to this message:
 Message 146 by robinrohan, posted 05-12-2006 5:33 PM kuresu has not yet responded

    
robinrohan
Inactive Member


Message 146 of 170 (311507)
05-12-2006 5:33 PM
Reply to: Message 145 by kuresu
05-12-2006 5:31 PM


Re: Heritable traits
it has everything to do with the parents. my objection was when you said that in order to pass on the gene the person with it needed to mate with the "right person".

OK, I must be confused about who's being born homozygous dominant. I thought you meant the offspring of the one with the positive trait.


This message is a reply to:
 Message 145 by kuresu, posted 05-12-2006 5:31 PM kuresu has not yet responded

  
kuresu
Member (Idle past 804 days)
Posts: 2544
From: boulder, colorado
Joined: 03-24-2006


Message 147 of 170 (311510)
05-12-2006 5:38 PM
Reply to: Message 140 by robinrohan
05-12-2006 5:06 PM


Re: Heritable traits
not only this appearance of a positive trait but also that individual has to mate with the right partner

you and I seem to be misunderstanding each other, and the post I'm replying to is where it's starts, I think.

in the quote, do you mean by appearance the phenotypical expression of the gene? phenotype is the physical characteristics of the organism. Genotype is the genetic characteristics of the organism. genotype controls phenotype.


This message is a reply to:
 Message 140 by robinrohan, posted 05-12-2006 5:06 PM robinrohan has responded

Replies to this message:
 Message 148 by robinrohan, posted 05-12-2006 5:45 PM kuresu has responded

    
robinrohan
Inactive Member


Message 148 of 170 (311515)
05-12-2006 5:45 PM
Reply to: Message 147 by kuresu
05-12-2006 5:38 PM


Re: Heritable traits
in the quote, do you mean by appearance the phenotypical expression of the gene? phenotype is the physical characteristics of the organism. Genotype is the genetic characteristics of the organism. genotype controls phenotype.

I have that terminology down. But something can be passed on either recessively or dominantly. Just because it's recessive, it doesn't mean it can't appear later. I thought you were saying that there was one unlikely scenario in which the positive trait would not be passed down at all.

Come to think of it though, if it doesn't appear in the phenotype (if it's recessive), it wouldn't affect survival rate, I would assume.


This message is a reply to:
 Message 147 by kuresu, posted 05-12-2006 5:38 PM kuresu has responded

Replies to this message:
 Message 149 by kuresu, posted 05-12-2006 6:05 PM robinrohan has responded

  
kuresu
Member (Idle past 804 days)
Posts: 2544
From: boulder, colorado
Joined: 03-24-2006


Message 149 of 170 (311523)
05-12-2006 6:05 PM
Reply to: Message 148 by robinrohan
05-12-2006 5:45 PM


Re: Heritable traits
i was. it's a highly unlikely event when the single gene is considered. If two are considered, such as eye color and skin color, and if they are linked or not linked, that event becomes more likely, but I don't know how to do linked gene crosses.

it woulnd't affect survival rate, but it could still be passed down, and that increases the chance of two heterozygotes in a population mating. Then there would be a homozygous recessive.

Taking the example differently. If the blue eye was dominant over brown eye, then you end up with the trait being passed down much more easily. And not all mutations are not recessive, so . . .


This message is a reply to:
 Message 148 by robinrohan, posted 05-12-2006 5:45 PM robinrohan has responded

Replies to this message:
 Message 150 by robinrohan, posted 05-12-2006 6:08 PM kuresu has responded

    
robinrohan
Inactive Member


Message 150 of 170 (311524)
05-12-2006 6:08 PM
Reply to: Message 149 by kuresu
05-12-2006 6:05 PM


Re: Heritable traits
i was

OK, but just to clear this up, it doesn't have anything to do with the partner? It's just about the genetic make-up of the individual with the positive trait?


This message is a reply to:
 Message 149 by kuresu, posted 05-12-2006 6:05 PM kuresu has responded

Replies to this message:
 Message 151 by kuresu, posted 05-12-2006 7:07 PM robinrohan has responded

  
Newer Topic | Older Topic
Jump to:


Copyright 2001-2018 by EvC Forum, All Rights Reserved

™ Version 4.0 Beta
Innovative software from Qwixotic © 2019