* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Looking at karyotypes
Causes of transsexuality wikipedia , lookup
Genome evolution wikipedia , lookup
Epigenetics of neurodegenerative diseases wikipedia , lookup
Medical genetics wikipedia , lookup
Segmental Duplication on the Human Y Chromosome wikipedia , lookup
Gene expression profiling wikipedia , lookup
Biology and consumer behaviour wikipedia , lookup
Point mutation wikipedia , lookup
Biology and sexual orientation wikipedia , lookup
Saethre–Chotzen syndrome wikipedia , lookup
Designer baby wikipedia , lookup
Down syndrome wikipedia , lookup
Microevolution wikipedia , lookup
Genomic imprinting wikipedia , lookup
Polycomb Group Proteins and Cancer wikipedia , lookup
Gene expression programming wikipedia , lookup
Epigenetics of human development wikipedia , lookup
Artificial gene synthesis wikipedia , lookup
Skewed X-inactivation wikipedia , lookup
Genome (book) wikipedia , lookup
Y chromosome wikipedia , lookup
X-inactivation wikipedia , lookup
Activity AB1.8 Looking at karyotypes To answer 1. Why do individuals have 2 copies of each chromosome? 2. What is a karyotype? 3. In a karyotype chromosomes are arranged according to size and which 2 other factors are considered? 4. What difference is there between the male and the female karyotype? The karyotype of a person with Klinefelter’s syndrome is shown below. 5. Describe how the Klinefelter’s karyotype is different. Klinefelter’s syndrome produces a sterile male with female features and small testes. 6. Explain why a person with Klinefelter’s syndrome is male, not female, even though they have two X chromosomes. 7. Half of all miscarriages are due to chromosome abnormalities. This means that parts of chromosomes are missing or duplicated. Using your knowledge of how genes affect development, suggest why chromosome abnormalities usually cause serious symptoms in an individual. Answers 1. One from each parent 1 2. Diagram showing the chromosomes possessed by an individual 1 3. Shape and banding 1 4. Pair 23 is either XX female or XY male 1 5. Have an extra sex chromosome (X) chromosome – XXY 1 6. Y chromosome carries the SRY gene; produces testosterone – male hormone; embryo develops into a male 2 7. genes code for a protein; if a gene is missing then a particular protein is not made or an enzyme is missing; if the chromosome is duplicated then too much of the protein / enzyme is produced 3