2. INHERITANCE OF SEX
Heterochromosomes genes that determine sex, are in a pair of
chromosomes being different in shape and size.
Remain 22 pairs of chromosomes autosomes.
Somatic cells: 44 autosomes + 2 sex chromosomes.
FEMALE MALE
22 22
autosomes autosomes
XX XY
Any numerical aberration is considered a mutation disease.
Klinefelter’s syndrome karyotype 47, XXY: male phenotype, femenine
characteristics.
3. SEX-LINKED INHERITANCE RARE DISEASE
Gene not determining a sex Low incidence in the
characteristic located on X population.
chromosome. Only affect less than 5 per
Hemophilia and colour 10.000 inhabitants.
blindness: X-linked. WHO: approximately 700 rare
Y-linked women could not have diseases affecting 7% of the
that allele. world population.
Passed on from fathers to sons Spain: 3 million people with
rare diseases.
5. FATTY ACIDS and MYELIN
Long chains of hydrocarbons with a carboxyl terminal.
Saturated fatty acids single bonds which in the carbon atoms surrounded
by hydrogen atoms.
Unsaturateddouble bonds.
Monounsaturated single double bond.
Polyunsaturated 2 or more double bonds present in a long chain fatty acid.
Myelin
Lipoprotein that covers the axon of neurons.
Propagates the electrical impulses along neurons much faster.
Demyelination: slows electrical condution decreasing normal functional
activity.