B6

• What does DNA stand for?


  Deoxyribonucleic acid
• What is DNA made of?

  Lots of similar units stuck together
• What shape does DNA form?

  Double helix
• If you unraveled DNA from a single cell, how long would it be?

  Over two meters long
• How is DNA organized in a cell?

  Separated into 46 different sections
• What do we call the tightly coiled sections of DNA?

  Chromosomes
• How many chromosomes does each human cell have?

  46 chromosomes
• How many different types of chromosomes are there?

  23 different types
• What do we call the pairs of chromosomes?

  Chromosome pairs
• What are the sex chromosomes in humans?

  X and Y chromosomes
• How many X chromosomes do women have?

  Two X chromosomes
• How many X and Y chromosomes do men have?

  One X and one Y chromosome
• When do chromosomes appear in an X shape?

  Just before cell division
• What is a gene?

  A small section of DNA coding for protein
• What does a gene code for?

  A particular sequence of amino acids
• How many different types of amino acids are there?

  20 different types
• How do amino acids form proteins?

  By combining in different sequences
• How does DNA influence cell type?

  Determines which proteins the cell produces
• What protein do red blood cells need to transport oxygen?

  Hemoglobin
• What is a genome?

  The entire set of genetic material
• How does an individual's genome compare to others?

  It differs from strangers but is similar to parents
• What can scientists do with the complete human genome?

  Identify genes linked to diseases
• What is an inherited disease?

  A disease caused by inherited genes
• How can genes affect disease risk?

  They may increase the risk of certain diseases
• What can doctors do by looking at genes?

  Choose more effective treatments
• What determines the type of cell produced?

  The proteins the cell produces
• Why do red blood cells need hemoglobin?

  To transport oxygen around the body
• What is a genome?

  The entire set of genetic material in an organism
• How can genes affect disease risk?

  They may increase the risk of diseases
• What are the relationships between DNA, chromosomes, genes, and genomes?

  • DNA is the genetic material.
  • Chromosomes are tightly coiled DNA sections.
  • Genes are segments of DNA coding for proteins.
  • The genome is the complete set of genetic material.
• What are the differences between X and Y chromosomes?

  • X chromosome: present in both genders.
  • Y chromosome: present only in males.
  • Females have two X chromosomes.
  • Males have one X and one Y chromosome.
• What are the implications of understanding the human genome?

  • Identifying disease-linked genes.
  • Developing better treatments.
  • Tracing human ancestry and migrations.
• What is an allele?

  A different version of the same gene
• What is the difference between dominant and recessive alleles?

  Dominant alleles are expressed over recessive ones
• What does homozygous mean?

  Having two identical alleles for a gene
• What does heterozygous mean?

  Having two different alleles for a gene
• What is the relationship between genotype and phenotype?

  Genotype determines the phenotype characteristics
• How do genes influence traits?

  They determine characteristics we develop
• Can a single gene determine a trait?

  Yes, sometimes traits are single-gene determined
• What is an example of a trait determined by a single gene?

  Fur color in mice