Concept 7 All cells arise from pre-existing cells.
Cross pure-bred pea plants to identify dominant flower color.
HI! The common fruit fly is a favorite organism used by many genetic researchers. Let's look at the chromosome number of fruit flies. If fruit fly skin cells have eight chromosomes, how many chromosomes do fruit fly wing cells have? 8. That is correct. 4. No, try again. 16. No, that's too many. 0; only cells on the body have chromosomes. No, cells have chromosomes no matter where they are located. With the exception of sex cells (eggs and sperm), there will be the same number of chromosomes in all cells of the body. If fruit fly skin cells have eight chromosomes then wing cells will also have eight chromosomes. These body (somatic) cells undergo mitosis. Fruit fly somatic cells have eight chromosomes. During the metaphase stage of mitosis, how many chromatids are there? 4. No, there are more than 4 chromatids. 8. No, 8 is the chromosome number. 16. That is correct. 32. No, a fruit fly cell will not have 32 chromatids. There are two chromatids for every chromosome. Fruit flies have 16 chromatids during the metaphase stage of mitosis. At the end of mitosis, how many chromosomes does each daughter cell have? There are 32 chromosomes in each daughter cell. No, a fruit fly cell will not have 32 chromosomes. One cell will have 16 chromosomes, the other will have none. No, both daughter cells will have the same number of chromosomes. Each daughter cell will have 16 chromosomes. No, the cells have divided. Each daughter cell will not have 16 chromosomes. Each daughter cell will have 8 chromosomes. That is correct. By the end of mitosis, there are two daughter cells. Each daughter cell will have the same amount of genetic material as the parent – 8 chromosomes.