BIO Exercise 7, Mitosis and Meiosis
Question # 00050649
Posted By:
Updated on: 02/24/2015 11:21 PM Due on: 02/25/2015
Exercise 7, Mitosis and Meiosis
Activity 1, Mitosis, #1-4
1. If an organism has a diploid chromosome number of 20 and goes through mitosis, how many chromosomes will be present in each of the daughter cells? __________
2. Why does the rate of chromosome duplication increase when you get a cut?
3. What would happen if mitosis could no longer occur in an adult plant or animal? Would this be a problem? Explain.
4. Predict the relative rate of mitosis in a tree in your backyard during the four seasons of the year. Explain.
Activity 2, Stages of the cell cycle in the onion root tip, #1-7
1. Based on the descriptions of the stages of mitosis in Table 7-1, label the following events in the photographs in Figure 7-5: (i.e., in what stage of mitosis do these events occur?)
New cell wall starts to form __________
First appearance of individual chromosomes ___________
Start of separation of two sets of chromosomes ___________
Chromosomes line up in the center of the cell ___________
Daughter cells formed ______________
Cell not undergoing mitosis _____________
Table 7-2
Number of cells in each stage of the cell cycle
Interphase Prophase Metaphase Anaphase Telophase
Figure 7-6a
Figure 7-6b
Figure 7-7a
Figure 7-7b
Figure 7-8a
Figure 7-8b
Figure 7-9a
Figure 7-9b
Totals
3. Which stage of the cell cycle is the mode? ____________
4. Which stage of mitosis is the mode? _____________
5. Based on the number of cells you counted in each stage of the cell cycle, in which stage does a cell spend most of its time? ________________
6. Based on the number of cells you counted in each stage of mitosis, which stage takes the longest to complete? __________________
7. If you were looking at the photograph in Figure 7-8a three weeks after your initial count, would the distribution of the stages appear exactly the same? Explain.
Activity 3, Introduction to meiosis, # 1-5
1. In a cell with four chromosomes, there would be ______ pairs of chromosomes.
Each of these pairs would have _____ maternal and _____ paternal chromosome(s).
2. In figure 7-11a (mitosis), the parent cell contains _____ chromosomes and each daughter cell contains _____ chromosomes.
The daughter cells produced by mitosis are genetically ____________ each other.
The daughter cells produced by mitosis are genetically ____________ the parent cell.
The daughter cells produced by mitosis are _________.
The daughter cells produced by meiosis are _________.
3. In figure 7-11b (meiosis), the parent cell contains ______ chromosomes and each daughter cell contains _____ chromosomes.
The daughter cells produced by meiosis are genetically ____________ each other.
The daughter cells produced by meiosis are genetically ____________ the parent cell.
Each of the daughter cells contains ______ of the chromosomes from each pair.
4. If the diploid parent cell in figure 7-11b had eight chromosomes, how many chromosomes would be present in each daughter cell? ______
5. Because of a fertility problem, your eggs were fertilized in vitro and several embryos were frozen. If you examined one of the frozen embryos, would you expect mitosis or meiosis to be occurring in the cells? Explain.
Activity 4, Genetic diversity, #1, 2, 4, 5, and 7
1. Before crossing over occurs, are the two chromatids of the maternal chromosome identical? _____
After crossing over occurs, are the two chromatids of the maternal chromosome identical? _____
2. The event that ensures that a baby will have the normal (diploid) number of chromosomes is ___________. Explain.
4. As the number of chromosome pairs increases, the number of possible gametes __________.
5. Based only on the effects of random assortment, how many possible different genetic combinations exist each time an egg is fertilized? ____________
7. List and explain the two events that occur in meiosis that act to increase genetic diversity within a species.
Activity 1, Mitosis, #1-4
1. If an organism has a diploid chromosome number of 20 and goes through mitosis, how many chromosomes will be present in each of the daughter cells? __________
2. Why does the rate of chromosome duplication increase when you get a cut?
3. What would happen if mitosis could no longer occur in an adult plant or animal? Would this be a problem? Explain.
4. Predict the relative rate of mitosis in a tree in your backyard during the four seasons of the year. Explain.
Activity 2, Stages of the cell cycle in the onion root tip, #1-7
1. Based on the descriptions of the stages of mitosis in Table 7-1, label the following events in the photographs in Figure 7-5: (i.e., in what stage of mitosis do these events occur?)
New cell wall starts to form __________
First appearance of individual chromosomes ___________
Start of separation of two sets of chromosomes ___________
Chromosomes line up in the center of the cell ___________
Daughter cells formed ______________
Cell not undergoing mitosis _____________
Table 7-2
Number of cells in each stage of the cell cycle
Interphase Prophase Metaphase Anaphase Telophase
Figure 7-6a
Figure 7-6b
Figure 7-7a
Figure 7-7b
Figure 7-8a
Figure 7-8b
Figure 7-9a
Figure 7-9b
Totals
3. Which stage of the cell cycle is the mode? ____________
4. Which stage of mitosis is the mode? _____________
5. Based on the number of cells you counted in each stage of the cell cycle, in which stage does a cell spend most of its time? ________________
6. Based on the number of cells you counted in each stage of mitosis, which stage takes the longest to complete? __________________
7. If you were looking at the photograph in Figure 7-8a three weeks after your initial count, would the distribution of the stages appear exactly the same? Explain.
Activity 3, Introduction to meiosis, # 1-5
1. In a cell with four chromosomes, there would be ______ pairs of chromosomes.
Each of these pairs would have _____ maternal and _____ paternal chromosome(s).
2. In figure 7-11a (mitosis), the parent cell contains _____ chromosomes and each daughter cell contains _____ chromosomes.
The daughter cells produced by mitosis are genetically ____________ each other.
The daughter cells produced by mitosis are genetically ____________ the parent cell.
The daughter cells produced by mitosis are _________.
The daughter cells produced by meiosis are _________.
3. In figure 7-11b (meiosis), the parent cell contains ______ chromosomes and each daughter cell contains _____ chromosomes.
The daughter cells produced by meiosis are genetically ____________ each other.
The daughter cells produced by meiosis are genetically ____________ the parent cell.
Each of the daughter cells contains ______ of the chromosomes from each pair.
4. If the diploid parent cell in figure 7-11b had eight chromosomes, how many chromosomes would be present in each daughter cell? ______
5. Because of a fertility problem, your eggs were fertilized in vitro and several embryos were frozen. If you examined one of the frozen embryos, would you expect mitosis or meiosis to be occurring in the cells? Explain.
Activity 4, Genetic diversity, #1, 2, 4, 5, and 7
1. Before crossing over occurs, are the two chromatids of the maternal chromosome identical? _____
After crossing over occurs, are the two chromatids of the maternal chromosome identical? _____
2. The event that ensures that a baby will have the normal (diploid) number of chromosomes is ___________. Explain.
4. As the number of chromosome pairs increases, the number of possible gametes __________.
5. Based only on the effects of random assortment, how many possible different genetic combinations exist each time an egg is fertilized? ____________
7. List and explain the two events that occur in meiosis that act to increase genetic diversity within a species.
-
Rating:
/5
Solution: BIO Exercise 7, Mitosis and Meiosis (Solution)