Mitosis Lab Report PDF

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This is the basis of a mitosis lab. An A average was made on these reports....

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BIOL 1111L Clayton State University

Lab Topic 9 Mitosis Written by Nikki T. Sawyer, Clayton State University, Morrow GA (2014)

Objectives Upon completion of this exercise, students should be able to  Define and use the terms in bold from this laboratory exercise  Describe the stages of interphase  Describe the stages of mitosis (prophase, metaphase, anaphase, telophase)  Describe the process of cytokinesis and how it differs in animal cells and plants cells  Identify each stage of mitosis by examining pictures of plants cells and animal cells

Introduction All new cells come from previously existing cells. New cells are formed by the process of cell division which involves both replication of the cell’s nucleus (mitosis) and division of the cytoplasm (cytokinesis). It is imperative that the DNA be moved in an extremely efficient manner during division. If the DNA were to be moved in a way that jeopardizes the integrity of its code, the resulting cells would have defective information that would likely to lead to the new cell’s dysfunction or death. Cell division is just one part of a larger cell cycle. The cell cycle includes all of the mitotic phases plus the intervening interphase. The total time required for the completion of one cell cycle varies from one organism to the next and varies between tissues of the same organism. In general, cells spend about 90% of their time in interphase. The interphase portion of the cell cycle can be further broken down into G1, S, and G2 phases. There is also a G0 phase for non-dividing cells. You will learn about the events that occur during each of these phases as you complete the virtual mitosis lab. Once a cell has received a signal directing it to divide, the nucleus and the duplicated chromosomes (sister chromatids) within it are separated during the process of mitosis, and the cytoplasm and organelles are separated in the process of cytokinesis. These processes result in two identical copies of the original cell. These two identical copies are called daughter cells. Mitosis can be divided into four general stages: prophase, metaphase, anaphase, and telophase. In some textbooks, the events that occur during prophase are broken down into an early prophase and a late prophase (or prometaphase) stage. For this lab, you will only focus on the four main stages and events that occur during prometaphase will be included with the prophase stage. You will learn about these events and the events that occur during the other mitotic stages as you complete the virtual mitosis lab. After the nucleus has been replicated, the cytoplasm and its organelles is divided through a process called cytokinesis. The process of cytokinesis usually begins concurrently with the telophase stage of mitosis. The process of cytokinesis is different in animal cells and plant cells. This difference is due to the fact that plant cells have cell walls and animal cells do not have cell walls. Therefore, the outer surface of a plant cell is more rigid than the outer surface of an animal cell, necessitating different methods of dividing the cell as a whole. You will learn about cytokinesis in both plant cells and animal cells as you complete the virtual lab.

BIOL 1111L Clayton State University

Finally, you will also learn how to identify the stages of mitosis and cytokinesis by examining pictures of cells as you complete the virtual lab. As you work through the virtual lab, complete the report sheet provided. You can find the questions and images in the virtual lab.

BIOL 1111L Clayton State University

Name ______________________________________________________

Mitosis Lab Report Answer the questions provided in your virtual lab. Exercise 1: Interphase 1.1

Three things that occur in interphase include:   

the production of new organelles, increase volume of cytoplasm, and division of mitochondria and chloroplasts, which is all done in the G1 Phase DNA replication, which occurs in the S Phase Final growth, which occurs in the G2 Phase

1.2

To visually determine whether a cell is in interphase, you should look for an intact, solid nucleus. Individual chromosomes will not be easily seen.

1.3

a. Frequently dividing cell type: Skin cells

b. Infrequently dividing cell type: Liver Cells

c. How would they differ in interphase? The interphase of skin cells would be much faster due to the fact that they divide and grow more frequently than liver cells.

Exercise 2: Mitosis 2.1

a. Number of cells at the beginning of mitosis: 1 b. Number of cells at the end of mitosis: 2

BIOL 1111L Clayton State University

c. Similarity of daughter cells to each other: Daughter cells are very much alike despite the fact that they are separated from the parent cell. They are very identical to each other, sharing the exact same DNA.

2.2

a. Prophase

d. Prophase

b. Telophase

e. Metaphase

c. anaphase

f. Prophase

2.3 Chromosomes condense before mitosis so that they are able to move smoothly in between each face and not become fragile, or breakable.

Exercise 3: Mitosis Stage Identification Look at the pictures of cells provided in your virtual lab. Identify the stage of mitosis (prophase, metaphase, anaphase, telophase) for each picture provided. 3.1 Anaphase

3.5 Prophase

3.2 Prophase

3.6 Telophase

3.3 Metaphase

3.7 Anaphase

3.4 Telophase

3.8 Metaphase

Exercise 4: Cytokinesis 4.1 Cytokinesis differs in plant cells and animal cells due to the fact that plant cells have cell walls and animal cells do not.

BIOL 1111L Clayton State University

4.2 cell plate

4.3 contractile ring

4.4 The process of cytokinesis involves the division of the cytoplasm and all of the enclosed organelles....