Chapter 06: Genetics Ibsen: Oral Pathology for the Dental Hygienist, 7th Edition MULTIPLE CHOICE 1. Which statement is correct concerning chromosomes? a. Chromosomes are located in the of the cell. b. Mature germ cells (ova and spermatozoa) contain 46 chromosomes. c. Chromosomes can only be seen clearly under a microscope when the nucleus and
cell are dividing. d. Chromosomes contain RNA, which directs the production of amino acids,
polypeptides, and proteins by the cell. ANS: C
Chromosomes can only be seen clearly under a microscope when the nucleus and cell are dividing. At other times the genetic material is dispersed in the nucleus. Chromosomes are located in the nucleus of the cell. They contain the hereditary units called genes that are transmitted from one generation to another. Each cell of the human body, with the exception of mature germ cells, has 46 chromosomes. Half of these chromosomes are derived from the father and the other half from the mother. Chromosomes contain DNA, which directs the production of amino acids, polypeptides, and proteins by the cell. REF: Chromosomes, page 188
OBJ: 1
2. The gap 2 (G2) phase of mitosis a. begins when mitotic division ends. b. ends when mitotic division begins. c. precedes the S phase. d. is when replication of DNA takes place. ANS: B
The G2 phase of mitosis ends when mitotic division takes place and follows the S phase. Replication of DNA takes place in the S phase. The gap 2 (G2) phase of mitosis ends when mitotic division begins. The G2 phase of mitosis follows the S phase. Replication of DNA takes place during the S phase. REF: Mitosis, page 188
OBJ: 2
3. The correct order for the stages of mitosis is a. prophase, anaphase, metaphase, telophase. b. prophase, metaphase, anaphase, telophase. c. prophase, metaphase, telophase, anaphase. d. metaphase, prophase, telophase, anaphase. ANS: B
