Please enable JavaScript.

Coggle requires JavaScript to display documents.

Chapter 15 - Coggle Diagram

- - - - Banding pattern
      - Location of centromere
      - Chromosome composition within a given
        species tends to remain relatively constant Humans - 2 sets of 23
        chromosomes (total of 46) Dog - 2 sets of 39 chromosomes (total of 78) Fruit fly - 2 sets of 4 chromosomes (total of 8) Tomato - 2 sets of 12 chromosomes (total of 24)
      - Giemsa stain
        gives G banding
      - .
        
        Short arm is p, long arm is q
        
        Metacentric – middle
        
        Submetacentric – off center
        
        Acrocentric – near end
        
        Telocentric – at the end
- - - - Euploid refers to the normal number of chromosomes, where two sets are typical in a diploid organism.
      - Polyploid refers to organisms with three or more sets of chromosomes, such as triploid (3n) or tetraploid (4n).
      - .
        
        Aneuploidy: Abnormal number
        
        of a particular chromosome:
        
        Trisomic: Refers to having three copies of a chromosome, such as in trisomy 21 (Down syndrome), where there are two normal copies of a chromosome plus a third (2n+1).
        
        Aneuploidy: An abnormal number of a particular chromosome.
        Monosomic: Missing one normal copy of a chromosome (2n-1).
        
        Nondisjunction: A failure of chromosomes to sort properly during cell division, which can lead to the production of aneuploid gametes during meiosis.
- - - - Variations in chromosome structure and number can significantly impact organisms, leading to several human diseases and playing a key role in the evolution of new species.
      - Chromosome variation occurs when the structure or number of chromosomes changes, making an individual different from others of the same species (abnormal). However, between species, variations in chromosome structure and number are normal.