BIOL 1010 Online
Define and discuss karyotyping.
Explain homologous chromosomes.
Understand gender identification with X and Y.
Describe gender development.
Explain X linked traits.
DNA is packaged inside the eukaryotic cell as
. Chromosomes are rod-
like structures containing both DNA and associated proteins called
number of chromosomes varies with each species but there are 46 chromosomes in
or body cells. These 46 chromosomes can be grouped into pairs called
based on centromere location and size of the chromosome. Of the
23 pairs, 22 pairs are
(non-sex chromosomes) and 1 pair represents the
consisting of an X and either another X, if the individual is female,
or a Y, if male. Of the autosomes, the largest pair is designated as pair 1 and the
smallest is designated as pair 22. During genetic testing, a
chromosomes is performed.
are arranged as pairs and
large chromosomal abnormalities can be detected. Any extra (Trisomy 21/Down’s
Syndrome or Klinefelter’s Syndrome) or missing (Turner’s Syndrome) chromosomes
indicate an abnormal karyotype. For example, Down’s Syndrome is denoted by the
presence of three #21 chromosomes. Therefore, an individual with Down’s syndrome