Chapter 10 Mitosis and Chapter 11.4 Meiosis Test review Name______

(answer key)

Vocabulary Terms:

Define each of the following terms.

Mitosis:division of the cell nucleus (chromosomes)

Cell Division:process by which a cell divides into two daughter cells

Cell Cycle:is the series of events that cells go through as they grow and divide

Chromosome:threadlike structure within the nucleus containing genetic information that is passedfrom parent to offspring. Two sister chromatids attached at the center by a centromere.

Sister Chromatid: one of two identical “sister” parts of a duplicated chromosome

Centromere:area where chromatids of a chromosome are attached

Spindles:fanlike microtubule structure that helps separate chromosomes during mitosis and meiosis

Haploid:cell that contains only a single set of chromosomes and therefore only a single set of genes ( 23 humans)

Diploid:refers to a cell that contains both sets of homologous chromosomes (humans 46)

Gamete:specialized cell involved in sexual reproduction (sex cells) eggs and sperm

Sex Cell: eggs and sperm , gametes

Meiosis:process by which the number of chromosomes per cell is cut in half through separation of homologous chromosomes in a diploid cell.

Crossing Over: process in which homologous chromosomes exchange portions of their chromatids during meiosis

Homologous Chromosome:chromosomes that each have a corresponding chromosome from the opposite sex parent, matching in size , shape , bands of DNA

Cell Plate:formed during plant cytokinesis, divides the cytoplasm and organelles in plant cell division

Centrioles:structures located in the cytoplasm of animal cells used to divide the chromosome

Tetrad:structure containing 4 chromatids that form during prophase I of meiosis

Fill in the blank

  1. As a cell becomes larger, its volume increases faster than its surface area. This places demands on the cells _DNA_, and makes it difficult to take in adequate nutrients and expel wastes.
  2. Chromosomes become visible during Cell Division and specifically in prophase.
  3. The cell cycle includes G1, G2, S phases, and M phase.
  4. The cell cycle is the series of events that cells go through as they grow and divide.
  5. When cells come in contact with other cells they stop growing.
  6. Controls on cell growth and division can be turned on and off.
  7. Cancer is a disorder in which some cells have lost their ability to control their growth rate.
  8. Cancer cells form masses of cells called tumors.
  9. An organisms diploid number is 14, its haploid number is7.
  10. Gametes (sex cells) have one allele for each gene.
  11. Gametes are produced by the process ofMeiosis.
  12. Chromosomes form tetrads during Prophase I of meiosis.
  13. Unlike mitosis, meiosis results in the formation of 4 (#) genetically different cells.
  14. A cell that has 5 chromosomes in the G1 phase will have 10 (#) chromatids in the G2 phase.
  15. The number of sister chromatids in a human body cell entering cell division is 92 (#).

Short Answer

  1. Name factors that help to regulate the timing of the cell cycle?Contact with other cells, cyclins, growth factors, and any other internal or external regulator.

17.During which two phase of mitosis are chromosomes visible? Prophase and Metaphase

  1. Draw and Label a chromosome with centromere and sister chromatids?
  1. Describe cytokinesis and explain the differences between plant and animal cytokinesis? Cytokinesis is the division of the cytoplasm and organelles, plant cells form a cell plate, and animal cells have cleavage furrow or pinching in.
  1. Briefly describe G1, S, G2, and M phases of cell division?

G1= cell Growth S phase= DNA synthesis G2= preparation for cell divison(mitosis)

  1. Explain the differences in the number of cells produced in meiosis for females vs. males? Females produce 1 egg and 3 polar bodies, males produce four sperm (genetically different)
  1. Explain why the daughter cells produced by meiosis are genetically different from each other, whereas cells produced by mitosis are not?Daughter cells produced in meiosis are genetically different from each other because during meiosis homologous chromosomes in parent cell form tetrads and then separate. As a result, each daughter cell receives one chromosome from each homologous pair; the chromosome it receives is random. Thus each daughter cell has a different combination of chromosomes. Also because crossing over during prophase I may result in new gene combinations. In mitosis, homologous chromosomes usually do not form tetrads and separate, therefore crossing over usually does not occur.

23. Explain why only mutations occurring in gametes (sex cells) can be passed on to offspring? Meiosis creates sex cells used in reproduction. The egg and sperm both haploid, unite to form a diploid zygote , any change in the DNA(mutation) is then passed to the offspring. Mitosis is the process of producing genetically identical body cell, which would not affect future offspring.

24List two problems that growth causes for cells? As a cell grows larger, more demands are placed on its DNA, and the cell has more trouble moving enough nutrients and wastes across the cell membrane.

25 Describe what events occur during Interphase? G1, S phase, G2

26. What are some factors that can stop cells from growing?.Contact with other cells, chemotherapy, growth inhibitors

27. Homologous chromosomes are the two sets of chromosomes found in a body cell- one set inherited from the male parent and the other inherited from the female parent.

28. Mitosis produces diploid cells, whereas meiosis produces haploid gametes. Mitosis cells are genetically identical to the parent cell and meiosis cells are genetically different.

29. Cancer cells left untreated can form a mass called a tumor, which can then have cells break loose and spread throughout the body disrupting normal cell activities and causing serious medical problems.

30. Cancer can be treated by radiation or chemotherapy as well as removing cancerous cells, to avoid cancer you should stay away from cancer causing agents.