5.3 Mapping Distance

Question 1

Experiments performed by Sturtevant allowed scientists to map genes and their locations on chromosomes. What is a linkage map?

Answer 1

Genetic map that is based on recombination frequencies

Question 2

The distance between genes are called ___ ____.

Answer 2

Map units

Question 3

ONE map unit is equivalent to a __ recombination frequency. What does this represent?

Answer 3

• 1%

- express the relative distance along chromosomes

Question 4

What does 50% recombination mean in terms of mapping distance?

Answer 4

• genes that are far apart on the same xme or on two different xmes

Question 5

Non-nuclear DNA: Some traits are located on ___ found in the ___ or chloroplasts.

Answer 5

• DNA

- mitochondria

Question 6

Both chloroplasts and mitochondria are randomly assorted to gametes and daughter cells. What does this mean in terms of inheritance of mitochondrial DNA? (2)

Answer 6

• in animals, mitochondria are transmitted by the egg, NOT sperm
• therefore ALL mitochondrial DNA is maternally inherited

Question 7

Both chloroplasts and mitochondria are randomly assorted to gametes and daughter cells. What does this mean in terms of plants and inheritance? (2)

Answer 7

• in plants, mitochondria and chloroplasts are transmitted in the ovule, NOT the pollen
• therefore, both mitochondrial and chloroplast determined traits are maternally inherited?