The Cell Cycle and Mitosis

  1. a) How many cells do you have in your body?

b)How many new cells does your body produce every minute?

c)Why do some cells divide often, while others either do not divide in adult life, or

do so after many years?

  1. List the three stages of the cell cycle and describe each.

Stage / Description /
  1. Interphase is the longest stage of the cell cycle. What three events take place during interphase?
  1. a) What does the word replication mean?

b) What is being copied during the replication stage of interphase?

c)Why is DNA replication so important?

  1. Why is chromatin in its loosely coiled form during interphase?

  1. In the final stage before cell division, what organelles will be duplicated and why?
  1. What is the purpose ofmitosis?
  1. Complete this flow chart:

DNA/Proteins (double helix)  chromatin (loosely coiled) 

  1. Chromosomes are X shaped during prophase. Label this diagram with the words centromere, sister chromatids, duplicated DNA & proteins.

10. In the boxes found below:

  • name and draw each phase of MITOSIS
  • describe what is happening in the phase

Phase 1: ______

Description: /

Phase 2: ______

Description:

Phase 3: ______

Description: /

Phase 4: ______

Description:
  1. Mitosis only occurs in cells that are about to divide. Some cells undergo mitosis more often (i.e. stomach cells), while others remain in the interphase stage for a long period of time (i.e. brain cells). Why do you think some cells undergo mitosis more often than other cells?
  1. Why do you think it is important that DNA is compact and tightly coiled during

mitosis (in the form of chromosomes)?

  1. DNA replication and mitosis are highly controlled. If they weren't, there may be many errors in the bases causing mutations. Some cells may receive more chromosomes in the daughter cells while other daughter cells received less. What might happen to the cells if this happened?
  1. a) What is the importance of checkpoints in the cell cycle?

b)Why might a cell not divide?

Asexual Reproduction

  1. Define asexual reproduction:
  1. a) Fill in the diagram below about asexual reproductionwith the followings words: parent cell, daughter cell, 46 chromosomes

b) Are the daughter cells identical OR not identical to the parent cell?

  1. Fill the table below about the different types of asexual reproduction.

Type / Description / Diagram / Types of Species
A single parent replicates its genetic material and divides into two equal parts.
Areas of an individual undergo repeated mitosis and cell division and can develop into an identical organism.
Each fragment of an organism develops into a clone of its parent.
Special cells divide repeatedly to form structures that will eventually develop into a plant identical to the parent.
Form single-celled spores. Spores are a reproductive cell that grows into a new individual by mitosis.
  1. How does budding in yeast differ from binary fission in amoebas?

Budding in Yeast / Binary Fission in Amoebas
  1. List the advantages and disadvantages of asexual reproduction in the table below.

Advantage / Disadvantage
  1. Define clone:
  1. What is the purpose of human-assisted cloning?
  1. What isreproductive cloning?
  1. What is therapeutic cloning?
  1. Define stem cells.

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