Lesson 14: Genetics

Question 1

What sort of experiments did Gregor Mendel carry out in the mid- 19th century?

Answer 1

• 19th century: Gregor Mendel carried out breeding experiments on plants.

Question 2

What was one of the observations from Gregor Mendel’s experiments where he bred plants?

Answer 2

• One of his observations was that the inheritence of each characteristic is determined by “units” that are passed on to descendents unchanged.

Question 3

What was observed in the late 19th century?

Answer 3

• In the late 19th century behaviour of chromosomes during cell division
  was observed.

Question 4

What was observed in the early 20th century? What idea did this lead to?

Answer 4

• In the early- 20th century, it was observed that chromosomes and Mendel’s units behaved in similar ways.
• This led to the idea that the units, now called genes, were located on chromosomes.

Question 5

What was determined and the mechanism of what was worked out in the mid-20th century?

Answer 5

• In the mid-20th century the structure of DNA was determined and the mechanism of gene function worked out.

Question 6

What led to the gene theory being developed?

Answer 6

• This scientific work by many scientists led to the gene theory being
  developed.

Question 7

Why was the importance of Mendel’s discovery only recognised after his death?

Answer 7

• At the time, scientists did not understand how inheritene worked (DNA hadn’t been discovered yet.)
• Many scientists believed that characteristics were “blended” when inherited.