CRI2231 Chapter 3 (15 questions).docx

1\. What is the primary role of DNA in genetics? a\) To provide energy for cells b\) To store genetic information and direct cell activities c\) To regulate body temperature d\) To produce nutrients for the body 2\. During which stage of prenatal development does the blastocyst form? a\) Germi...

1\. What is the primary role of DNA in genetics? a\) To provide energy for cells b\) To store genetic information and direct cell activities c\) To regulate body temperature d\) To produce nutrients for the body 2\. During which stage of prenatal development does the blastocyst form? a\) Germinal stage b\) Embryonic stage c\) Foetal stage d\) Birth stage 3\. Which process is responsible for creating gametes with half the number of chromosomes? a\) Mitosis b\) Meiosis c\) Fertilisation d\) Cross-over 4\. What is the significance of the SRY gene in prenatal development? a\) It determines the skin colour of the foetus b\) It triggers the development of male sex organs c\) It regulates brain development d\) It prevents genetic abnormalities 5\. Which of the following is a recessive genetic disorder? a\) Huntington\'s disease b\) Cystic fibrosis c\) Polydactyly d\) Marfan syndrome 6\. How do polygenic traits differ from single-gene traits? a\) Polygenic traits are influenced by multiple genes and environmental factors b\) Polygenic traits are inherited through a single gene from one parent c\) Polygenic traits do not vary across different individuals d\) Polygenic traits only affect physical characteristics 7\. What is the primary focus of genetic counselling? a\) To cure genetic disorders before birth b\) To assess the risk of genetic disorders and guide parental decision-making c\) To modify the genetic makeup of embryos d\) To ensure all pregnancies are successful 8\. Which chromosomal disorder is associated with an extra twenty-first chromosome? a\) Klinefelter syndrome b\) Turner syndrome c\) Down syndrome d\) Fragile X syndrome 9\. What is the purpose of amniocentesis in prenatal diagnosis? a\) To treat genetic disorders in utero b\) To detect chromosomal abnormalities in the foetus c\) To increase the likelihood of a healthy pregnancy d\) To determine the gender of the baby 10\. In the context of genetics, what does the term \"range of reaction\" refer to? a\) The specific environment that determines a trait b\) The range of possible phenotypes based on genetic and environmental interactions c\) The predetermined outcome of genetic inheritance d\) The variability of a trait within a single individual 11\. How do dominant gene disorders differ from recessive gene disorders? a\) Dominant disorders require both parents to pass on the gene b\) Dominant disorders are always more severe than recessive disorders c\) Dominant disorders manifest even if only one parent passes on the gene d\) Dominant disorders are less likely to be inherited than recessive disorders 12\. What is the role of the placenta during prenatal development? a\) To produce hormones that stimulate foetal growth b\) To protect the foetus from all external influences c\) To facilitate the exchange of nutrients and waste between mother and foetus d\) To determine the foetus\'s genetic traits 13\. Which prenatal diagnostic technique carries the lowest risk of miscarriage? a\) Amniocentesis b\) Chorionic villus sampling (CVS) c\) Ultrasound d\) Foetoscopy 14\. What is an example of a sex-linked recessive trait? a\) Huntington\'s disease b\) Haemophilia c\) Polydactyly d\) Cystic fibrosis 15\. What does the term \"genomic imprinting\" refer to in genetics? a\) The process by which genes are silenced in a cell b\) The differential expression of a gene depending on whether it is inherited from the mother or father c\) The replication of DNA during cell division d\) The mutation of genes due to environmental factors Answer Key ========== b\) To store genetic information and direct cell activities a\) Germinal stage b\) Meiosis b\) It triggers the development of male sex organs b\) Cystic fibrosis a\) Polygenic traits are influenced by multiple genes and environmental factors b\) To assess the risk of genetic disorders and guide parental decision-making c\) Down syndrome b\) To detect chromosomal abnormalities in the foetus b\) The range of possible phenotypes based on genetic and environmental interactions c\) Dominant disorders manifest even if only one parent passes on the gene c\) To facilitate the exchange of nutrients and waste between mother and foetus c\) Ultrasound b\) Haemophilia b\) The differential expression of a gene depending on whether it is inherited from the mother or father