1. Cell Reproduction Review

2. How do cells reproduce?
Cell division

3. What is binary fission?
A form of cell division in which a prokaryotic cell divides into two cells that identical in size and genetic content

4. What kind of cell is a bacterium (prokaryote or eukaryote)?

5. How do bacteria reproduce?
Binary fission
Is this a type of asexual or sexual reproduction?
Asexual

6. What are the 3 main steps involved in binary fission
What are the 3 main steps involved in binary fission? Draw and describe each step. 1.
DNA is replicated
(See pic below) 2.
Cell wall and cell membrane forms between the 2 chromosomes. (See pic below) 3.
Two new daughter cells form. (See pic below)

7. 6. What is the cell cycle?
Sequence of events in the growth and division of a eukaryotic cell

8. 7. What are the phases of the cell cycle? (Draw a Diagram and label)

9. 8. Mitosis Nuclear Division Cytokinesis Ctyoplasmic Division
What happens during each phase of the cell cycle? 8.
Interphase
G1: Cell Growth
S: Synthesis of DNA (DNA Replication)
G2: Cell Growth, Organelles are copied
Mitosis
Nuclear Division
Cytokinesis
Ctyoplasmic Division

10. 9. What can cause normal cells to become cancerous? Broken cell cycle
Including:
Regulation of cell division is lost
Cells don’t respond normally to control mechanisms
Cells continue to divide without passing through G1

11. 10. What type of cells reproduce faster (prokaryote or eukaryote)?
Prokaryotes (Some as fast as every 20 minutes)

12. 11. What are chromosomes?
Strands of DNA that determine the genetic blueprint of the cell

13. 12. Each species of organism has a specific chromosome number.
How many chromosomes do bacteria have? 1
How many chromosomes do humans have in each body cell? 46

14. 13. Are the chromosomes visible in the eukaryotic cell during interphase?No
What do you call the chromosomal material at this time?
Chromatin

15. 14. When do chromosomes become visible in the cell?
During the first phase of mitosis (prophase)

16. 15. Label the diagram of how chromosomes look when they first become visible in the cell?
A: Chromosome/Sister chromatids (Chromatids are two copies of the same chromosome as the result of DNA replication)
B: Centromere (structure that holds the two chromatids together)
C: Chromatid

17. 16. What are somatic cells?
All the cells in an organism that ARE NOT the sex cells

18. 17. How many chromosomes are found in each human somatic cell?46

19. 18. What are homologous chromosomes?
Pairs of chromosomes that contain genes coding for the same traits (one from mother, one from father)

20. 19. How many pairs of homologous chromosomes are found in each human somatic cell?

21. 20. One homologue in each pair comes from the organism’s ___________ and the other homologue in each pair comes from the organism’s ________.
Mother, Father

22. 21. How do you refer to a cell that contains 2 sets of chromosomes (homologous chromosomes)?
Diploid

23. 22. How is the diploid number of a cell represented?
2n (where n = number of different chromosomes)

24. 23. What is the diploid number of human somatic cells?46

25. 24. What are gametes?
Sex cells (sperm and egg cells)

26. 25. How do you refer to a cell that contains only 1 set of chromosomes?
Haploid

27. 26. How is the haploid number of a cell represented?

28. 27. What is the haploid number of human gametes?23

29. 28. What is a karyotype?
A photo of the chromosome in a dividing cell that shows the chromosomes arranged by size, shape, and banding pattern.

30. 29. What is the purpose of doing a karyotype?
To determine the chromosome number of an organism and see if there are any abnormalities.

31. 30. Look at the karyotype and complete 1-4 in the box:
Put a box around the autosomes
Put a circle around the sex chromosomes
Is this normal or abnormal karyotype?
Male or female?

32. 31. What are autosomes?
Chromosomes that are not directly involved in determining the gender (sex) of an organism.
33. How many autosomes do human somatic cells have?
44 total or 22 pairs

33. 32. What are sex chromosomes?
Chromosomes directly involved in determining the gender (sex) of an organism.
34. How many sex chromosomes do human somatic cells have?
2 total or 1 pair

34. 35. What are the two types of sex chromosomes?
X and Y
36. What 2 sex chromosomes do human males have? And females?
Male = XY Female = XX

35. 37. Who determines the gender (sex) of a human child? And why?
Male. Females can only donate an X chromosome, but males can donate either an X or Y.

36. 38. How many autosomes do human gametes have
38. How many autosomes do human gametes have? ______ total (no pairs because gametes are haploid). 22
39. How many sex chromosomes do human gametes have? 1

37. 40. What is mitosis?
Division of a cell’s two nuclei (2 sets of chromosomes)

38. 41. Label the 4 sub phases of mitosis (in order) and write the major event in that phase.

39. Prophase:
Chromatin in the nucleus begins to condense and becomes visible in the light microscope as chromosomes
The nucleolus and nuclear membrane disappears
Centrioles begin moving to opposite ends of the cell
Spindle begins to form
Metaphase
Chromosomes line up along the middle (equator) of the cell
Anaphase
Sister chromatids separate at the centromere and move to opposite sides of the cell
Telophase
New nuclear membranes form around the daughter nuclei
Chromosomes uncoil and are no longer visible under the light microscope
Spindle fibers disappears
Cytokinesis or the partitioning of the cell may also begin during this stage

40. 42. What is cytokinesis?
Division of a cell’s cytoplasm to form two new daughter cells

41. 43. What is meisosis?
Type of cell division that produces the gametes (sex cells) of organisms.

42. 44. List the 8 sub phases of meiosis (in order)
Meiosis 1: Prophase I, Metaphase I, Anaphase I, Telophase I
Meiosis 2: Prophase II, Metaphase II, Anaphase II, Telophase II

43. 45. What are the main differences between Meiosis I and II?
Meiosis 1 = homologous chromosomes match up, line up and separate; chromosome numbers go from diploid to haploid
Meiosis 2 = Chromosomes line up and sister chromatids separate; chromosome number goes from haploid to haploid (just like mitosis, but cells haploid)

44. 46. What is crossing-over?
Exchange of genetic material between homologous chromosome that results in genetic recombination.
THIS IS WHY YOU ARE SO UNIQUE!!!
When does it occur?
Prophase I of Meiosis I

45. 47. Look on the second to last page of your foldable notes to fill in this table!!!
You must know this entire table for the test!

46. 48. What is spermatogenesis
Process in which sperm cells are made
How many are made? Do they all survive?
4 and yes!
How do they compare in size?
All the same size!

47. 49. What is oogenesis?
Process in which egg cells (ova) are made
How many egg cells are made? Do they all survive?
4, no (1 large egg cell survives)
Are they all the same size?
1 large cell and 3 smaller ones

48. 50. What is fertilization?
Union of a sperm and egg cell as a result of sexual reproduction.

49. 51. What is a zygote?
A fertilized egg

50. 52. What is nondisjunction?
When chromosomes don’t separate properly during meiosis, which causes the gametes to have an abnormal number of chromosomes (1 or 3).

51. 53. What is trisomy?
3 copies of the same chromosome are found in a cell
Ex: Trisomy 21 (Down Syndrome), Trisomy 18 (Edward’s syndrome)

52. 54. What is monosomy?

53. 55. What happens to offspring that receive an abnormal number of chromosomes?

54. 56. What are mutations?
A change in the nucleotide sequence of a DNA molecule