Karyotypes Karyotypes DefinitionDefinition - A picture of chromosomes cut out and grouped together. Typical human karyotype: 46 total chromosomes 23 total pairs 44 autosomes 2 sex chromosomes (XX or XY) An embryo without an X chromosome is incapable of survival Is the following individual male or female? Is this karyotype of a male or female? question here] A.Male[Option 1] B.Female Normal Human Female Normal Human Female Why? Because she lacks a Y chromosome. Is the following individual male or female? Is this karyotype of a male or female? question here] A.Male[Option 1] B.Female Normal Human Male Normal Human Male Why? Because he has a Y chromosome. Non-disjunction Non-disjunction is a failure of chromosomes to properly separate during either Stage 1 or Stage 2 of meiosis Upon fertilization the zygote may have one too many chromosomes ( trisomy) or one too few chromosomes (monosomy) Which chromosome number shows non-disjunction? (Enter the number of the chromosome. Use 23 for the X/Y chromosomes) Monosomy X Female Turner Syndrome Pectus excavatum (picture) Short stature Webbed neck Abnormal eye features (drooping eyelids) Absent or retarded development of secondary sexual characteristics that normally appear at puberty Infertility Dry eyes Which chromosome number shows non-disjunction? (Enter the number of the chromosome. Use 23 for the X/Y chromosomes) Trisomy 21 Down Syndrome Female Down Syndrome Most commonly known trisonomy 1:700 births; 1 in 6 die within 1 st year Average age is 16.2 years Common facial feature Short stature Stubby fingers and toes Large tongue makes speech difficult Which chromosome number shows non-disjunction? (Enter the number of the chromosome. Use 23 for the X/Y chromosomes) Patau Syndrome (Trisomy 13) 1:15,000 births as most fetuses die before term Of those that survive, 5% live to age 3; 45% die within the first month Serious eye, brain, and circulatory defects Which chromosome number shows non-disjunction? (Enter the number of the chromosome. Use 23 for the X/Y chromosomes) XXY Klinefelter Syndrome Tall (around six feet) Hypogonadism (small testes) Unable to produce sperm (infertile) Sparse facial and body hair Gynecomastia (male breast disorder) Which chromosome number shows non-disjunction? (Enter the number of the chromosome. Use 23 for the X/Y chromosomes) XYY Jacobs Syndrome Tend to have a wiry-build Severe acne Minor birth defects Minor outturning of the elbows Fertility is not affected
