Science quiz 7.2

If fruit flies have eight chromosomes in their body (somatic) cells, how many chromosomes would they have in their sex cells?

If dog sex cells have 39 chromosomes, how may chromosomes are in their body (somatic) cells?

Which genetic disease played a role in the downfall of the Russian monarchy?

Is chromosome number a good predictor of the complexity of the organism?

The expected number of chromosomes in human body cells is 46. Fruit flies have only 8 chromosomes, mulberry trees have 308, and protists can have thousands. Dogs are in the middle of the range, with 78 chromosomes. How many chromosomes are in the sex cells of each of these organisms?

Genetic disorders can result from a missing piece of a chromosome. Cri du chat syndrome is caused by a shortened chromosome 5. In French, the name means “cat’s cry”. Babies with cri du chat syndrome make a cry like a kitten. Cri du chat causes many physical and mental symptoms. What is a person with an incomplete chromosome missing?

When a plant produces pollen cells with half the chromosomes of the parent cells it has completed:

When a bacterium divides to make two identical daughter cells it has completed:

When a skin cell divides rapidly to replace tissue damaged by a scrape it has completed:

Mitchell’s family has the unusual trait of having an extra finger. Many members of his family were born with an extra finger, which is a recessive trait. At a family dinner, Mitchell’s grandmother helped him sketch a pedigree of the family. Dark-shaded family members were born with an extra finger. No shading indicates people who do not have an extra finger. A question mark means it is unknown. Mitchell is #8 on the pedigree and Mitchell’s grandmother is #2. Based on the pedigree, what do you predict for family members #11, #12, and #13?