× Didn't find what you were looking for? Ask a question
Top Posters
Since Sunday
L
3
d
3
y
3
a
3
n
3
d
3
e
3
d
3
c
3
p
3
M
3
a
3
New Topic  
emilyliv emilyliv
wrote...
Posts: 154
Rep: 3 0
4 years ago
When it comes to karyotypes, why do the chromosomes have to be arranged from largest to smallest?
Read 67 times
2 Replies

Related Topics

Replies
wrote...
Educator
4 years ago
When it comes to karyotypes, why do the chromosomes have to be arranged from largest to smallest?

I'd assume that chromosomes labelled 1 through 22 are based on size. By labelling them from largest to smallest, you can easily identify which is chromosome 1, 2, etc. The 23rd pair are the sex chromosomes, they're arranged at the end. If it's a female, they'll match, if a male, they don't.

From my research, the chromosomes are cut out and arranged according to a convention, called the Denver classification, that was established by a group of geneticists.

                                                                                                                                       
     

            Table       of Denver Chromosome Classification            

   
     

Chromosome       Group            

   
     

Chromosome       number            

   
     

Description       of chromosomes            

   
     

A            

   
     

1       - 3            

   
     

Large,       metacentric            

   
     

B            

   
     

4       - 5            

   
     

Large,       submetacentric            

   
     

C            

   
     

6       - 12            

   
     

Medium-sized,       submetacentric; X chromosome closely resembles pair number 6, longest in       group            

   
     

D            

   
     

13       - 15            

   
     

Medium-sized,       acrocentric; all three pairs with satellites on short arm            

   
     

E            

   
     

16       - 18            

   
     

Smallest       of the medium-sized; pair 16 metacentric; others submetacentric            

   
     

F            

   
     

19       - 20            

   
     

Short,       metacentric            

   
     

G             

     

21       - 22            

   
     

very       short; acrocentric; both with satellites            

   
emilyliv Author
wrote...
4 years ago
Thanks that helped!
New Topic      
Explore
Post your homework questions and get free online help from our incredible volunteers
  950 People Browsing
Related Images
  
 290
  
 108
  
 310
Your Opinion
How often do you eat-out per week?
Votes: 81

Previous poll results: Who's your favorite biologist?