Why is Chromosome 1 called Chromosome 1?Does every mitochondrion in a cell contain the same DNA?How are 23 chromosomes in human sperm chosen?What determines the number of chromosomes an organism carries?What does it mean to “map the human genome”How do chromosome pairs get “paired up” for protein synthesis?Polymorphism in number of chromosomes?How does DNA from sperm fuse with DNA in egg?Zygosity and StrandsWhat exactly happens during the crossoverWith over 400 chromosomes, does mitosis in a species of butterfly happen in the same way as in humans?
Have made several mistakes during the course of my PhD. Can't help but feel resentment. Can I get some advice about how to move forward?
Does git delete empty folders?
Why doesn't mathematics collapse down, even though humans quite often make mistakes in their proofs?
How to translate 脑袋短路 into English?
Vegetarian dishes on Russian trains (European part)
Levenshtein Neighbours
Why did St. Jerome use "virago" in Gen. 2:23?
Saying something to a foreign coworker who uses "you people"
What is the evidence on the danger of feeding whole blueberries and grapes to infants and toddlers?
Why should I pay for an SSL certificate?
Why is su world executable?
Check disk usage of files returned with spaces
The Lucky House
Did Wernher von Braun really have a "Saturn V painted as the V2"?
What are these protruding elements from SU-27's tail?
What can I do to keep a threaded bolt from falling out of it’s slot
How do neutron star binaries form?
Show two plots together: a two dimensional curve tangent to the maxima of a three dimensional plot
Independence of Mean and Variance of Discrete Uniform Distributions
Repurpose telephone line to ethernet
Polar contour plot in Mathematica?
Do banks' profitability really suffer under low interest rates
Number of matrices with bounded products of rows and columns
Control GPIO pins from C
Why is Chromosome 1 called Chromosome 1?
Does every mitochondrion in a cell contain the same DNA?How are 23 chromosomes in human sperm chosen?What determines the number of chromosomes an organism carries?What does it mean to “map the human genome”How do chromosome pairs get “paired up” for protein synthesis?Polymorphism in number of chromosomes?How does DNA from sperm fuse with DNA in egg?Zygosity and StrandsWhat exactly happens during the crossoverWith over 400 chromosomes, does mitosis in a species of butterfly happen in the same way as in humans?
.everyoneloves__top-leaderboard:empty,.everyoneloves__mid-leaderboard:empty,.everyoneloves__bot-mid-leaderboard:empty margin-bottom:0;
$begingroup$
Chromosome 1 is the designation for the largest human chromosome. Humans have two copies of chromosome 1, as they do with all of the autosomes, which are the non-sex chromosomes. Chromosome 1 spans about 249 million nucleotide base pairs, which are the basic units of information for DNA. It represents about 8% of the total DNA in human cells.
Why is Chromosome 1 called Chromosome 1? Is being the largest human chromosome the only reason?
chromosome
asked Aug 6 at 15:31
fu DLfu DL
2181 silver badge5 bronze badges
$endgroup$
|
show 2 more comments
$begingroup$
Chromosome 1 is the designation for the largest human chromosome. Humans have two copies of chromosome 1, as they do with all of the autosomes, which are the non-sex chromosomes. Chromosome 1 spans about 249 million nucleotide base pairs, which are the basic units of information for DNA. It represents about 8% of the total DNA in human cells.
Why is Chromosome 1 called Chromosome 1? Is being the largest human chromosome the only reason?
chromosome
asked Aug 6 at 15:31
fu DLfu DL
2181 silver badge5 bronze badges
$endgroup$
10
$begingroup$
If they had started with the smallest, then what if one is found later that was missed because of its small size? If you start from the largest, that's less of a problem.
$endgroup$
– forest
Aug 7 at 3:14
18
$begingroup$
Because biologists aren't C-language coders :-)
$endgroup$
– Carl Witthoft
Aug 7 at 13:27
2
$begingroup$
@forest Or, as apparently happened, if the smallest one was found to be an artifact: until 1956 it was 'accepted as fact' that humans contained 48 chromosomes! See Can't any body count?
$endgroup$
– user1136
Aug 7 at 20:20
4
$begingroup$
@forest But it would have been much more embarrassing if they'd started with the largest and then found a larger one! (I'm looking at you, zeroth law of thermodynamics.)
$endgroup$
– David Richerby
Aug 8 at 17:12
1
$begingroup$
@user1136 Is there some reason it's written "any body" (this is the actual title of the paper) or do I need to write a follow-up called "Can Anybody Spell?"
$endgroup$
– David Richerby
Aug 8 at 17:17
|
show 2 more comments
$begingroup$
Chromosome 1 is the designation for the largest human chromosome. Humans have two copies of chromosome 1, as they do with all of the autosomes, which are the non-sex chromosomes. Chromosome 1 spans about 249 million nucleotide base pairs, which are the basic units of information for DNA. It represents about 8% of the total DNA in human cells.
Why is Chromosome 1 called Chromosome 1? Is being the largest human chromosome the only reason?
chromosome
asked Aug 6 at 15:31
fu DLfu DL
2181 silver badge5 bronze badges
$endgroup$
Chromosome 1 is the designation for the largest human chromosome. Humans have two copies of chromosome 1, as they do with all of the autosomes, which are the non-sex chromosomes. Chromosome 1 spans about 249 million nucleotide base pairs, which are the basic units of information for DNA. It represents about 8% of the total DNA in human cells.
Why is Chromosome 1 called Chromosome 1? Is being the largest human chromosome the only reason?
chromosome
chromosome
asked Aug 6 at 15:31
fu DLfu DL
2181 silver badge5 bronze badges
asked Aug 6 at 15:31
fu DLfu DL
2181 silver badge5 bronze badges
asked Aug 6 at 15:31
fu DLfu DL
2181 silver badge5 bronze badges
asked Aug 6 at 15:31
fu DLfu DL
2181 silver badge5 bronze badges
asked Aug 6 at 15:31
fu DLfu DL
2181 silver badge5 bronze badges
2181 silver badge5 bronze badges
10
$begingroup$
If they had started with the smallest, then what if one is found later that was missed because of its small size? If you start from the largest, that's less of a problem.
$endgroup$
– forest
Aug 7 at 3:14
18
$begingroup$
Because biologists aren't C-language coders :-)
$endgroup$
– Carl Witthoft
Aug 7 at 13:27
2
$begingroup$
@forest Or, as apparently happened, if the smallest one was found to be an artifact: until 1956 it was 'accepted as fact' that humans contained 48 chromosomes! See Can't any body count?
$endgroup$
– user1136
Aug 7 at 20:20
4
$begingroup$
@forest But it would have been much more embarrassing if they'd started with the largest and then found a larger one! (I'm looking at you, zeroth law of thermodynamics.)
$endgroup$
– David Richerby
Aug 8 at 17:12
1
$begingroup$
@user1136 Is there some reason it's written "any body" (this is the actual title of the paper) or do I need to write a follow-up called "Can Anybody Spell?"
$endgroup$
– David Richerby
Aug 8 at 17:17
|
show 2 more comments
10
$begingroup$
If they had started with the smallest, then what if one is found later that was missed because of its small size? If you start from the largest, that's less of a problem.
$endgroup$
– forest
Aug 7 at 3:14
18
$begingroup$
Because biologists aren't C-language coders :-)
$endgroup$
– Carl Witthoft
Aug 7 at 13:27
2
$begingroup$
@forest Or, as apparently happened, if the smallest one was found to be an artifact: until 1956 it was 'accepted as fact' that humans contained 48 chromosomes! See Can't any body count?
$endgroup$
– user1136
Aug 7 at 20:20
4
$begingroup$
@forest But it would have been much more embarrassing if they'd started with the largest and then found a larger one! (I'm looking at you, zeroth law of thermodynamics.)
$endgroup$
– David Richerby
Aug 8 at 17:12
1
$begingroup$
@user1136 Is there some reason it's written "any body" (this is the actual title of the paper) or do I need to write a follow-up called "Can Anybody Spell?"
$endgroup$
– David Richerby
Aug 8 at 17:17
10
10
$begingroup$
If they had started with the smallest, then what if one is found later that was missed because of its small size? If you start from the largest, that's less of a problem.
$endgroup$
– forest
Aug 7 at 3:14
$begingroup$
If they had started with the smallest, then what if one is found later that was missed because of its small size? If you start from the largest, that's less of a problem.
$endgroup$
– forest
Aug 7 at 3:14
18
18
$begingroup$
Because biologists aren't C-language coders :-)
$endgroup$
– Carl Witthoft
Aug 7 at 13:27
$begingroup$
Because biologists aren't C-language coders :-)
$endgroup$
– Carl Witthoft
Aug 7 at 13:27
2
2
$begingroup$
@forest Or, as apparently happened, if the smallest one was found to be an artifact: until 1956 it was 'accepted as fact' that humans contained 48 chromosomes! See Can't any body count?
$endgroup$
– user1136
Aug 7 at 20:20
$begingroup$
@forest Or, as apparently happened, if the smallest one was found to be an artifact: until 1956 it was 'accepted as fact' that humans contained 48 chromosomes! See Can't any body count?
$endgroup$
– user1136
Aug 7 at 20:20
4
4
$begingroup$
@forest But it would have been much more embarrassing if they'd started with the largest and then found a larger one! (I'm looking at you, zeroth law of thermodynamics.)
$endgroup$
– David Richerby
Aug 8 at 17:12
$begingroup$
@forest But it would have been much more embarrassing if they'd started with the largest and then found a larger one! (I'm looking at you, zeroth law of thermodynamics.)
$endgroup$
– David Richerby
Aug 8 at 17:12
1
1
$begingroup$
@user1136 Is there some reason it's written "any body" (this is the actual title of the paper) or do I need to write a follow-up called "Can Anybody Spell?"
$endgroup$
– David Richerby
Aug 8 at 17:17
$begingroup$
@user1136 Is there some reason it's written "any body" (this is the actual title of the paper) or do I need to write a follow-up called "Can Anybody Spell?"
$endgroup$
– David Richerby
Aug 8 at 17:17
|
show 2 more comments
2 Answers
2
active
oldest
votes
$begingroup$
Chromosomes were first known about from karyograms (that's the word for chromosome pictures like these) sort of like this one (1)(2):
The scientists looking at these chromosomes didn't know much about them at first. They were discovered before anything was understood about genes, but by 1922 it was thought they were the carriers of genes. Without much understanding of the chromosomes, and certainly no understanding of what they carried, scientists needed an easy way to order and compare them. They chose a straight forward option - size - and paired them up and then lined them up biggest to smallest. Because the sex chromosomes didn't fit into this scheme of matching pairs they were left to the end.
Hence Chromosome 1 is Chromosome 1 because it is the largest autosomal chromosome.
Notes:
- The actual first karyogram was of a plant, this one is of a human male.
- The image above is public domain, obtained from Wikipedia, and originally made by the National Human Genome Research Institute.
answered Aug 6 at 18:10
Jack AidleyJack Aidley
6,26724 silver badges45 bronze badges
$endgroup$
3
$begingroup$
This also works for chromosomes in other species, but sometimes with complications due to interspecific phylogenetics. Chromosome 2 turned out to be two smaller primate chromosomes fused, and these half-chromosomes are now called 2A and 2B. In particular, in non-human primates this has required a renaming of chromosomes, and one that isn't as simple for them as numbering by size.
$endgroup$
– J.G.
Aug 7 at 7:58
$begingroup$
@user1136: double checking, I see that it was the first observation of chromosomes that was in 1842 but Karyograms were presumably a bit later. Human chromosomes are not the easiest to see so the science advanced in other organisms earlier
$endgroup$
– Jack Aidley
Aug 8 at 6:38
$begingroup$
It seems to me that most of the early 'chromosome counters' were concerned with 'how many' rather than 'taking a roll call'. One of the first to tabulate the chromosomes and to label the largest (in terms of length) 'Chromosome 1' is (Hsu, 1952). To quote from that paper (Fig 14): "Diagrammatic representation of the haploid set of human chromosomes including the sex pair... The autosomes are numbered according to their length, regardless of the position of the centromeres
$endgroup$
– user1136
Aug 12 at 9:40
$begingroup$
There is, of course, a glaring error in Fig. 14 of (Hsu, 1952): his diagram shows 48 chromosomes. (The definitive 'game-changing' paper giving the correct number of 46 is (Tjio & Levan, 1956)
$endgroup$
– user1136
Aug 12 at 9:52
add a comment |
$begingroup$
Size is a difficult one to judge when chromosomes are similar sizes, and it was more difficult before staining of the bands.
Because of this, some chromosome naming systems group chromosomes into different categories of the centromere type (acrocentric, telocentric), so the largest do not always necessarily descend in order of size. Some genomes still use a sub-classification system, such as Feline (A1, A2, B1, B2), though it is a lot easier to treat chromosomes numerically in programs.
answered Aug 8 at 17:18
Stephen DavisonStephen Davison
111 bronze badge
$endgroup$
$begingroup$
Welcome to Biology.SE! While interesting, this doesn't really answer the OP question. ——— Please take the tour and then consult the help pages on the standards for How to Answer effectively. Thanks! 😊
$endgroup$
– tyersome
Aug 9 at 16:30
add a comment |
Your Answer
StackExchange.ready(function()
var channelOptions =
tags: "".split(" "),
id: "375"
;
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function()
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled)
StackExchange.using("snippets", function()
createEditor();
);
else
createEditor();
);
function createEditor()
StackExchange.prepareEditor(
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: false,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: null,
bindNavPrevention: true,
postfix: "",
imageUploader:
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
,
noCode: true, onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
);
);
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function ()
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fbiology.stackexchange.com%2fquestions%2f85990%2fwhy-is-chromosome-1-called-chromosome-1%23new-answer', 'question_page');
);
Post as a guest
Required, but never shown
2 Answers
2
active
oldest
votes
2 Answers
2
active
oldest
votes
active
oldest
votes
active
oldest
votes
$begingroup$
Chromosomes were first known about from karyograms (that's the word for chromosome pictures like these) sort of like this one (1)(2):
The scientists looking at these chromosomes didn't know much about them at first. They were discovered before anything was understood about genes, but by 1922 it was thought they were the carriers of genes. Without much understanding of the chromosomes, and certainly no understanding of what they carried, scientists needed an easy way to order and compare them. They chose a straight forward option - size - and paired them up and then lined them up biggest to smallest. Because the sex chromosomes didn't fit into this scheme of matching pairs they were left to the end.
Hence Chromosome 1 is Chromosome 1 because it is the largest autosomal chromosome.
Notes:
- The actual first karyogram was of a plant, this one is of a human male.
- The image above is public domain, obtained from Wikipedia, and originally made by the National Human Genome Research Institute.
answered Aug 6 at 18:10
Jack AidleyJack Aidley
6,26724 silver badges45 bronze badges
$endgroup$
3
$begingroup$
This also works for chromosomes in other species, but sometimes with complications due to interspecific phylogenetics. Chromosome 2 turned out to be two smaller primate chromosomes fused, and these half-chromosomes are now called 2A and 2B. In particular, in non-human primates this has required a renaming of chromosomes, and one that isn't as simple for them as numbering by size.
$endgroup$
– J.G.
Aug 7 at 7:58
$begingroup$
@user1136: double checking, I see that it was the first observation of chromosomes that was in 1842 but Karyograms were presumably a bit later. Human chromosomes are not the easiest to see so the science advanced in other organisms earlier
$endgroup$
– Jack Aidley
Aug 8 at 6:38
$begingroup$
It seems to me that most of the early 'chromosome counters' were concerned with 'how many' rather than 'taking a roll call'. One of the first to tabulate the chromosomes and to label the largest (in terms of length) 'Chromosome 1' is (Hsu, 1952). To quote from that paper (Fig 14): "Diagrammatic representation of the haploid set of human chromosomes including the sex pair... The autosomes are numbered according to their length, regardless of the position of the centromeres
$endgroup$
– user1136
Aug 12 at 9:40
$begingroup$
There is, of course, a glaring error in Fig. 14 of (Hsu, 1952): his diagram shows 48 chromosomes. (The definitive 'game-changing' paper giving the correct number of 46 is (Tjio & Levan, 1956)
$endgroup$
– user1136
Aug 12 at 9:52
add a comment |
$begingroup$
Chromosomes were first known about from karyograms (that's the word for chromosome pictures like these) sort of like this one (1)(2):
The scientists looking at these chromosomes didn't know much about them at first. They were discovered before anything was understood about genes, but by 1922 it was thought they were the carriers of genes. Without much understanding of the chromosomes, and certainly no understanding of what they carried, scientists needed an easy way to order and compare them. They chose a straight forward option - size - and paired them up and then lined them up biggest to smallest. Because the sex chromosomes didn't fit into this scheme of matching pairs they were left to the end.
Hence Chromosome 1 is Chromosome 1 because it is the largest autosomal chromosome.
Notes:
- The actual first karyogram was of a plant, this one is of a human male.
- The image above is public domain, obtained from Wikipedia, and originally made by the National Human Genome Research Institute.
answered Aug 6 at 18:10
Jack AidleyJack Aidley
6,26724 silver badges45 bronze badges
$endgroup$
3
$begingroup$
This also works for chromosomes in other species, but sometimes with complications due to interspecific phylogenetics. Chromosome 2 turned out to be two smaller primate chromosomes fused, and these half-chromosomes are now called 2A and 2B. In particular, in non-human primates this has required a renaming of chromosomes, and one that isn't as simple for them as numbering by size.
$endgroup$
– J.G.
Aug 7 at 7:58
$begingroup$
@user1136: double checking, I see that it was the first observation of chromosomes that was in 1842 but Karyograms were presumably a bit later. Human chromosomes are not the easiest to see so the science advanced in other organisms earlier
$endgroup$
– Jack Aidley
Aug 8 at 6:38
$begingroup$
It seems to me that most of the early 'chromosome counters' were concerned with 'how many' rather than 'taking a roll call'. One of the first to tabulate the chromosomes and to label the largest (in terms of length) 'Chromosome 1' is (Hsu, 1952). To quote from that paper (Fig 14): "Diagrammatic representation of the haploid set of human chromosomes including the sex pair... The autosomes are numbered according to their length, regardless of the position of the centromeres
$endgroup$
– user1136
Aug 12 at 9:40
$begingroup$
There is, of course, a glaring error in Fig. 14 of (Hsu, 1952): his diagram shows 48 chromosomes. (The definitive 'game-changing' paper giving the correct number of 46 is (Tjio & Levan, 1956)
$endgroup$
– user1136
Aug 12 at 9:52
add a comment |
$begingroup$
Chromosomes were first known about from karyograms (that's the word for chromosome pictures like these) sort of like this one (1)(2):
The scientists looking at these chromosomes didn't know much about them at first. They were discovered before anything was understood about genes, but by 1922 it was thought they were the carriers of genes. Without much understanding of the chromosomes, and certainly no understanding of what they carried, scientists needed an easy way to order and compare them. They chose a straight forward option - size - and paired them up and then lined them up biggest to smallest. Because the sex chromosomes didn't fit into this scheme of matching pairs they were left to the end.
Hence Chromosome 1 is Chromosome 1 because it is the largest autosomal chromosome.
Notes:
- The actual first karyogram was of a plant, this one is of a human male.
- The image above is public domain, obtained from Wikipedia, and originally made by the National Human Genome Research Institute.
answered Aug 6 at 18:10
Jack AidleyJack Aidley
6,26724 silver badges45 bronze badges
$endgroup$
Chromosomes were first known about from karyograms (that's the word for chromosome pictures like these) sort of like this one (1)(2):
The scientists looking at these chromosomes didn't know much about them at first. They were discovered before anything was understood about genes, but by 1922 it was thought they were the carriers of genes. Without much understanding of the chromosomes, and certainly no understanding of what they carried, scientists needed an easy way to order and compare them. They chose a straight forward option - size - and paired them up and then lined them up biggest to smallest. Because the sex chromosomes didn't fit into this scheme of matching pairs they were left to the end.
Hence Chromosome 1 is Chromosome 1 because it is the largest autosomal chromosome.
Notes:
- The actual first karyogram was of a plant, this one is of a human male.
- The image above is public domain, obtained from Wikipedia, and originally made by the National Human Genome Research Institute.
answered Aug 6 at 18:10
Jack AidleyJack Aidley
6,26724 silver badges45 bronze badges
edited Aug 6 at 19:52
answered Aug 6 at 18:10
Jack AidleyJack Aidley
6,26724 silver badges45 bronze badges
answered Aug 6 at 18:10
Jack AidleyJack Aidley
6,26724 silver badges45 bronze badges
answered Aug 6 at 18:10
Jack AidleyJack Aidley
6,26724 silver badges45 bronze badges
6,26724 silver badges45 bronze badges
3
$begingroup$
This also works for chromosomes in other species, but sometimes with complications due to interspecific phylogenetics. Chromosome 2 turned out to be two smaller primate chromosomes fused, and these half-chromosomes are now called 2A and 2B. In particular, in non-human primates this has required a renaming of chromosomes, and one that isn't as simple for them as numbering by size.
$endgroup$
– J.G.
Aug 7 at 7:58
$begingroup$
@user1136: double checking, I see that it was the first observation of chromosomes that was in 1842 but Karyograms were presumably a bit later. Human chromosomes are not the easiest to see so the science advanced in other organisms earlier
$endgroup$
– Jack Aidley
Aug 8 at 6:38
$begingroup$
It seems to me that most of the early 'chromosome counters' were concerned with 'how many' rather than 'taking a roll call'. One of the first to tabulate the chromosomes and to label the largest (in terms of length) 'Chromosome 1' is (Hsu, 1952). To quote from that paper (Fig 14): "Diagrammatic representation of the haploid set of human chromosomes including the sex pair... The autosomes are numbered according to their length, regardless of the position of the centromeres
$endgroup$
– user1136
Aug 12 at 9:40
$begingroup$
There is, of course, a glaring error in Fig. 14 of (Hsu, 1952): his diagram shows 48 chromosomes. (The definitive 'game-changing' paper giving the correct number of 46 is (Tjio & Levan, 1956)
$endgroup$
– user1136
Aug 12 at 9:52
add a comment |
3
$begingroup$
This also works for chromosomes in other species, but sometimes with complications due to interspecific phylogenetics. Chromosome 2 turned out to be two smaller primate chromosomes fused, and these half-chromosomes are now called 2A and 2B. In particular, in non-human primates this has required a renaming of chromosomes, and one that isn't as simple for them as numbering by size.
$endgroup$
– J.G.
Aug 7 at 7:58
$begingroup$
@user1136: double checking, I see that it was the first observation of chromosomes that was in 1842 but Karyograms were presumably a bit later. Human chromosomes are not the easiest to see so the science advanced in other organisms earlier
$endgroup$
– Jack Aidley
Aug 8 at 6:38
$begingroup$
It seems to me that most of the early 'chromosome counters' were concerned with 'how many' rather than 'taking a roll call'. One of the first to tabulate the chromosomes and to label the largest (in terms of length) 'Chromosome 1' is (Hsu, 1952). To quote from that paper (Fig 14): "Diagrammatic representation of the haploid set of human chromosomes including the sex pair... The autosomes are numbered according to their length, regardless of the position of the centromeres
$endgroup$
– user1136
Aug 12 at 9:40
$begingroup$
There is, of course, a glaring error in Fig. 14 of (Hsu, 1952): his diagram shows 48 chromosomes. (The definitive 'game-changing' paper giving the correct number of 46 is (Tjio & Levan, 1956)
$endgroup$
– user1136
Aug 12 at 9:52
3
3
$begingroup$
This also works for chromosomes in other species, but sometimes with complications due to interspecific phylogenetics. Chromosome 2 turned out to be two smaller primate chromosomes fused, and these half-chromosomes are now called 2A and 2B. In particular, in non-human primates this has required a renaming of chromosomes, and one that isn't as simple for them as numbering by size.
$endgroup$
– J.G.
Aug 7 at 7:58
$begingroup$
This also works for chromosomes in other species, but sometimes with complications due to interspecific phylogenetics. Chromosome 2 turned out to be two smaller primate chromosomes fused, and these half-chromosomes are now called 2A and 2B. In particular, in non-human primates this has required a renaming of chromosomes, and one that isn't as simple for them as numbering by size.
$endgroup$
– J.G.
Aug 7 at 7:58
$begingroup$
@user1136: double checking, I see that it was the first observation of chromosomes that was in 1842 but Karyograms were presumably a bit later. Human chromosomes are not the easiest to see so the science advanced in other organisms earlier
$endgroup$
– Jack Aidley
Aug 8 at 6:38
$begingroup$
@user1136: double checking, I see that it was the first observation of chromosomes that was in 1842 but Karyograms were presumably a bit later. Human chromosomes are not the easiest to see so the science advanced in other organisms earlier
$endgroup$
– Jack Aidley
Aug 8 at 6:38
$begingroup$
It seems to me that most of the early 'chromosome counters' were concerned with 'how many' rather than 'taking a roll call'. One of the first to tabulate the chromosomes and to label the largest (in terms of length) 'Chromosome 1' is (Hsu, 1952). To quote from that paper (Fig 14): "Diagrammatic representation of the haploid set of human chromosomes including the sex pair... The autosomes are numbered according to their length, regardless of the position of the centromeres
$endgroup$
– user1136
Aug 12 at 9:40
$begingroup$
It seems to me that most of the early 'chromosome counters' were concerned with 'how many' rather than 'taking a roll call'. One of the first to tabulate the chromosomes and to label the largest (in terms of length) 'Chromosome 1' is (Hsu, 1952). To quote from that paper (Fig 14): "Diagrammatic representation of the haploid set of human chromosomes including the sex pair... The autosomes are numbered according to their length, regardless of the position of the centromeres
$endgroup$
– user1136
Aug 12 at 9:40
$begingroup$
There is, of course, a glaring error in Fig. 14 of (Hsu, 1952): his diagram shows 48 chromosomes. (The definitive 'game-changing' paper giving the correct number of 46 is (Tjio & Levan, 1956)
$endgroup$
– user1136
Aug 12 at 9:52
$begingroup$
There is, of course, a glaring error in Fig. 14 of (Hsu, 1952): his diagram shows 48 chromosomes. (The definitive 'game-changing' paper giving the correct number of 46 is (Tjio & Levan, 1956)
$endgroup$
– user1136
Aug 12 at 9:52
add a comment |
$begingroup$
Size is a difficult one to judge when chromosomes are similar sizes, and it was more difficult before staining of the bands.
Because of this, some chromosome naming systems group chromosomes into different categories of the centromere type (acrocentric, telocentric), so the largest do not always necessarily descend in order of size. Some genomes still use a sub-classification system, such as Feline (A1, A2, B1, B2), though it is a lot easier to treat chromosomes numerically in programs.
answered Aug 8 at 17:18
Stephen DavisonStephen Davison
111 bronze badge
$endgroup$
$begingroup$
Welcome to Biology.SE! While interesting, this doesn't really answer the OP question. ——— Please take the tour and then consult the help pages on the standards for How to Answer effectively. Thanks! 😊
$endgroup$
– tyersome
Aug 9 at 16:30
add a comment |
$begingroup$
Size is a difficult one to judge when chromosomes are similar sizes, and it was more difficult before staining of the bands.
Because of this, some chromosome naming systems group chromosomes into different categories of the centromere type (acrocentric, telocentric), so the largest do not always necessarily descend in order of size. Some genomes still use a sub-classification system, such as Feline (A1, A2, B1, B2), though it is a lot easier to treat chromosomes numerically in programs.
answered Aug 8 at 17:18
Stephen DavisonStephen Davison
111 bronze badge
$endgroup$
$begingroup$
Welcome to Biology.SE! While interesting, this doesn't really answer the OP question. ——— Please take the tour and then consult the help pages on the standards for How to Answer effectively. Thanks! 😊
$endgroup$
– tyersome
Aug 9 at 16:30
add a comment |
$begingroup$
Size is a difficult one to judge when chromosomes are similar sizes, and it was more difficult before staining of the bands.
Because of this, some chromosome naming systems group chromosomes into different categories of the centromere type (acrocentric, telocentric), so the largest do not always necessarily descend in order of size. Some genomes still use a sub-classification system, such as Feline (A1, A2, B1, B2), though it is a lot easier to treat chromosomes numerically in programs.
answered Aug 8 at 17:18
Stephen DavisonStephen Davison
111 bronze badge
$endgroup$
Size is a difficult one to judge when chromosomes are similar sizes, and it was more difficult before staining of the bands.
Because of this, some chromosome naming systems group chromosomes into different categories of the centromere type (acrocentric, telocentric), so the largest do not always necessarily descend in order of size. Some genomes still use a sub-classification system, such as Feline (A1, A2, B1, B2), though it is a lot easier to treat chromosomes numerically in programs.
answered Aug 8 at 17:18
Stephen DavisonStephen Davison
111 bronze badge
answered Aug 8 at 17:18
Stephen DavisonStephen Davison
111 bronze badge
answered Aug 8 at 17:18
Stephen DavisonStephen Davison
111 bronze badge
answered Aug 8 at 17:18
Stephen DavisonStephen Davison
111 bronze badge
111 bronze badge
$begingroup$
Welcome to Biology.SE! While interesting, this doesn't really answer the OP question. ——— Please take the tour and then consult the help pages on the standards for How to Answer effectively. Thanks! 😊
$endgroup$
– tyersome
Aug 9 at 16:30
add a comment |
$begingroup$
Welcome to Biology.SE! While interesting, this doesn't really answer the OP question. ——— Please take the tour and then consult the help pages on the standards for How to Answer effectively. Thanks! 😊
$endgroup$
– tyersome
Aug 9 at 16:30
$begingroup$
Welcome to Biology.SE! While interesting, this doesn't really answer the OP question. ——— Please take the tour and then consult the help pages on the standards for How to Answer effectively. Thanks! 😊
$endgroup$
– tyersome
Aug 9 at 16:30
$begingroup$
Welcome to Biology.SE! While interesting, this doesn't really answer the OP question. ——— Please take the tour and then consult the help pages on the standards for How to Answer effectively. Thanks! 😊
$endgroup$
– tyersome
Aug 9 at 16:30
add a comment |
Thanks for contributing an answer to Biology Stack Exchange!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
Use MathJax to format equations. MathJax reference.
To learn more, see our tips on writing great answers.
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function ()
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fbiology.stackexchange.com%2fquestions%2f85990%2fwhy-is-chromosome-1-called-chromosome-1%23new-answer', 'question_page');
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
10
$begingroup$
If they had started with the smallest, then what if one is found later that was missed because of its small size? If you start from the largest, that's less of a problem.
$endgroup$
– forest
Aug 7 at 3:14
18
$begingroup$
Because biologists aren't C-language coders :-)
$endgroup$
– Carl Witthoft
Aug 7 at 13:27
2
$begingroup$
@forest Or, as apparently happened, if the smallest one was found to be an artifact: until 1956 it was 'accepted as fact' that humans contained 48 chromosomes! See Can't any body count?
$endgroup$
– user1136
Aug 7 at 20:20
4
$begingroup$
@forest But it would have been much more embarrassing if they'd started with the largest and then found a larger one! (I'm looking at you, zeroth law of thermodynamics.)
$endgroup$
– David Richerby
Aug 8 at 17:12
1
$begingroup$
@user1136 Is there some reason it's written "any body" (this is the actual title of the paper) or do I need to write a follow-up called "Can Anybody Spell?"
$endgroup$
– David Richerby
Aug 8 at 17:17