chapter 14
What was the goal of the Human Genome Project?
To map and sequence all of the DNA in the human genome and identify all human genes.
Why is the X chromosome considered more important than the Y chromosome?
The X chromosome carries many essential genes needed for survival while the Y chromosome carries fewer genes and mainly determines male traits.
What is selective breeding?
It is when humans choose organisms with desired traits to reproduce.
Who was Charles Darwin and what did he propose about how species change over time?
Charles Darwin was a scientist who proposed that species evolve overtime through natural selection.
What is gel electrophoresis used for?
It is used to separate DNA fragments by size for purposes, such as forensics, paternity, testing, and genetic research.
A gel electrophoresis which DNA fragments move farther through the gel?
Smaller DNA fragments move farther because they pass more easily through the pores of the gel.
What does “survival of the fittest” mean in evolution?
It means individuals best adapted to their environment are more likely to survive and reproduce
How does geographic distribution relate to evolution?
Animals in different locations adapt to their environment and become different overtime.
Why is red-green color blindness more common in males??
It is an X-linked recessive trait, and males only have one X chromosome.
What is nondisjunction and what can it cause?
It is the failure of chromosomes to separate during meiosis, causing extra or missing chromosomes.
What is comparative embryology?
Comparing embryos of different species to see how they are alike in early development.
What is comparative anatomy?
Comparing body structures of different species to see similarities
What causes down syndrome and how does it usually occur?
An extra copy of chromosome 21 caused by nondisjunction.
What is the most common type of dwarfism and what causes it?
Achondroplasia, caused by a gene mutation that affects bone growth.
What is natural selection?
A process where organisms with helpful traits survive and pass those traits to their offspring.
How was Lamarck’s idea different from Darwin’s?
Lamarck thought organisms could pass on traits they gained during life, but Darwin believed traits, had to already be inherited.
What causes Tay - Sachs disease and how does it affect the brain?
A missing enzyme causes fatty substances to build up in the brain leading to nerve damage.
What causes cystic fibrosis and what body system systems does it affect?
A mutation in CTFR gene causes thick mucus that affects the lungs and digestive system.
How can natural selection lead to new species?
Over many generations, differences build up until groups can no longer reproduce with each other.
What is comparative biochemistry?
Comparing DNA or proteins of different organisms to see how closely related they are.