Chromosomes
,
genes &
karyotypes
Today’s
Helix
Complete Feedback
Rotational Graffiti & DNA stuffing
Mini Teach
Video
Karyotype Lab (outside?!)
2
COMPLET
E ME!
3
Pairs
activity
P. 14
5
Homologous Chromosomes
Chromosomes that
contain the same
sequence of genes as
another chromosome.
6
Genes & Alleles
Gene
Allele
A specific DNA
sequence that
expresses a trait. A
gene is part of a
chromosome and is
passed onto offspring.
A different form of the
same gene
7
Genes & Alleles
Gene
Allele
A specific DNA
sequence that
expresses a trait. A
gene is part of a
chromosome and is
passed onto offspring.
A different form of the
same gene
8
Chromosomes are paired
46 chromosomes in 23 pairs
• Two chromosomes specify sex
• XX for female and XY for male
• The rest (autosomes) are arranged in
pairs, numbered 1 through 22, from largest
to smallest.
9
Karyotype
A photograph
of pairs of
homologous
chromosome
s during
metaphase
10
Chromosomes
and
Karyotypes
Video: Amoeba Sisters (7:32 min)
h t t p s : //w w w.yo u t u b e .c o m/w a tch ? v=
m B q 1 U LW J p _ M
11
Karyotyping &
Genetic
By studying
karyotypes, we can become
Conditions
genetic detectives:
1. Look at the karyotype provided. How does
it differ from the person next to you? What
can you infer from the karyotype provided?
12
Karyotyping &
Genetic
2. Use
your karyotype as a template to
Conditions
compare with karyotypes of people (?) with
genetic conditions
3. Match up the karyotype with the
description of the genetic condition
13