Name ______Period:______

Biology I: DNA, Mitosis, and Meiosis Review

DNA

  1. Label the following parts on the picture: phosphate, sugar (deoxyribose), sugar phosphate backbone, hydrogen bond, nucleotide, nitrogen base, adenine, thymine, guanine, cytosine
  1. The nucleotide has three parts which include a ______, ______, and ______.

What part of the nucleotide directly codes for genetic traits? ______

  1. Adenine ( A) pairs with ______and Guanine (G) pairs with ______.

Therefore if 30% of bases in a DNA strand were composed of Guanine then… (HINT: all the percentages have to add to 100%!)

______% would be Cytosine.

______% would be Thymine.

______% would be Adenine.

  1. Write the complementary strand of DNA to the parent strand: TAGGCCTA
  1. In eukaryotes, DNA is located in which organelle? ______
  1. What is the process called when DNA copies itself? ______
  1. What type of DNA replication occurs in cells?(CIRCLE the correct answer)
  2. conservative: 2 old strands
  3. semi-conservative: 1 old strand/ 1 new strand
  4. liberal: 2 new strands

Mitosis

  1. Why do cells divide?
  1. What do spindle fibers do during mitosis?
  1. Cancer cells have lost the ability to control ______.
  1. The picture below shows the cell cycle. Label what is occurring in each stage on the chart. What parts of the cell cycle include interphase? ______
  1. Label the following parts of cell division on the picture below: interphase, prophase, metaphase, anaphase, telophase, centromere, spindle fibers, centriole. You need to make sure you can thoroughly describe all of these stages.

Meiosis

  1. What does haploid mean?
  1. What is the human haploid number? ______chromosomes
  1. What does diploid mean?
  1. What is the human diploid number? ______chromosomes
  1. In which phase does crossing over occur and what is the significance (purpose)?

15. Label these stages of meiosis below.

Place a check in the correct box for “mitosis,” “meiosis,” or “both.”

Mitosis / Meiosis / Both
16. Produces four cells from the original
17. A reduction division, meaning chromosome number is halved
18. Produces identical cells from the original
19. Crossing over occurs which creates genetic variation
20. DNAreplication occurs once during interphase before division
21. Produces two cells from the original
22. Has the step metaphase I and metaphase II
23. Produces diploid body cells
24. Produces haploidgametes (sex cells)
25. Produces different cells from the original
26. Involves chromosomes and spindle fibers
27. Would be performed by your skin cells during woundrepair