Genetics and Genomics

• When was the human genome sequenced?


  In 2003
• What does epigenetics explain?


  How different types of cells are formed from the same genome
• How does epigenetics influence gene expression?


  By controlling which genes are turned on or off
• What form is the genome found in all cells?

  Deoxyribonucleic acid (DNA)
• How is DNA organized in humans?


  Within chromosomes, of which humans have 46
• What is the role of most genes?


  To act as regulators for protein synthesis
• What are the building blocks of DNA?

  Nucleotides
• Which base pairs with adenine (A)?


  Thymine (T)
• What is translation?


  The process of reading mRNA to synthesize proteins
• When can chromosomes be observed?


  During the metaphase of cell division
• What type of cells contain 2 copies of each chromosome?


  Diploid cells
• What are gametes?


  Haploid cells containing one copy of each chromosome
• How do offspring inherit genes?


  They inherit a gene from each parent
• What is the purpose of mitosis?


  To replicate the genome for growth and cell renewal
• What happens during the cell cycle's interphase?


  DNA is replicated so that chromosomes have double their genetic information
• What are the main phases of mitosis?


  1. Prophase: Chromatin organizes into chromosomes
  2. Metaphase: Chromosomes align at the cell center
  3. Anaphase: Sister chromatids separate
  4. Telophase: Nuclear membranes form around each set of chromosomes
  5. Cytokinesis: Plasma membrane forms between the two new nuclei
• What is the outcome of meiosis?


  It produces gametes containing one chromosome from each of the 23 pairs
• What are the stages of meiosis?

  1. Meiosis 1:

  • Prophase 1: Tetrads form and recombination occurs
  • Metaphase 1: Chromosomes align at the cell center
  • Anaphase 1: Chromosome pairs separate
  • Telophase 1: Nuclear membranes form

  1. Meiosis 2:

  • Prophase 2: Chromosomes condense
  • Metaphase 2: Chromosomes align at the cell center
  • Anaphase 2: Sister chromatids separate
  • Telophase 2: Nuclear membranes form around each set
• What is recombination in meiosis?


  Exchanging segments of DNA between homologous chromatids
• What is independent assortment in meiosis?


  Random distribution of homologous pairs to create new cells
• What is a mutation?


  A mistake during DNA copying that changes the base sequence
• Where do most mutations occur?


  In the non-coding area of DNA
• How can mutations be inherited?


  They can occur during a person's life or be inherited
• What factors can increase the frequency of mutations?


  Chemical agents like radiation, UV light, alcohol, and tobacco
• From whom are new gene mutations predominantly inherited?


  From the father (~80%)
• How are genes inherited?


  In pairs, with different types called alleles
• What does homozygous mean?


  Having 2 identical alleles inherited
• What is a genotype?


  All the genes present in an individual's cells
• What causes single gene disorders?


  A mutation of a single gene
• What is an example of an autosomal recessive disorder?


  Cystic fibrosis
• What is Down's syndrome also known as?


  Trisomy 21
• What is Patau's syndrome also known as?


  Trisomy 13
• How are certain traits like eye color inherited?


  Through genetics, which determines how traits are passed down from generation to generation.
• What is the role of gene mutations in health conditions?


  They help determine the cause of health conditions.
• What does genomics consider compared to genetics?


  Genomics considers the whole genome rather than each individual gene.
• What does epigenetics involve?


  It includes genes that are expressed and controls gene activity.
• How do environmental factors impact epigenetics?


  They can turn genes on and off, influencing what an organism becomes.
• What do most genes code for?


  Most genes code for regulation and help produce various functions.
• What type of bonds form between DNA strands?


  Hydrogen bonds.
• What is required for proteins to be synthesized?


  Genes are required for the synthesis of proteins.