DNA 1 - Chromosomes, Genome & Migration

• What is DNA classified as?

  A polymer made of similar units
• How many strands does DNA have?

  Two strands
• What shape does DNA form?

  A 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 is unique about the 23rd pair of chromosomes?

  They are sex chromosomes
• What chromosomes do women have?

  Two X chromosomes
• What 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
• What determines the type of cell produced?

  The 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 their parents' genomes?

  More similar to parents than strangers
• What can scientists identify by studying the human genome?

  Genes linked to certain diseases
• What is an inherited disease?

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

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

  Choose more effective treatments
• How can genomes help trace human migrations?

  By showing genetic differences between populations
• What is the next topic to be discussed in the following video?

  Alleles, genotypes, and phenotypes