Biology Test 2
The first phase of mitosis is called
prophase
Which of the following is a phase of mitosis?
prophase
Cyclins are a family of closely related proteins that
regulate the cell cycle
When cytoplasm from a cell that is undergoing mitosis is injected into a cell that is in interphase, the second cell
enters mitosis
All of the following are problems that growth causes for cells EXCEPT (so what are the problems a cell experiences during growth?)
excess oxygen
If a normal cell divides, you can assume that
grown too large to meet its needs
Which of the following regulates the cell cycle?
growth factors, cyclins, p53
Cancer is a disorder in which some cells have lost the ability to control their
growth rate
As a cell grows, it
has more trouble moving enough materials across its cell membrane, places more demands on its DNA, and uses up food and oxygen more quickly ( all of the above)
The cell cycle is the
series of events that cells go through as they grow and divide
What is the role of the spindle during mitosis?
It helps separate the chromosomes
During which phase of mitosis do the chromosomes line up along the middle of the dividing cell?
Metaphase
When during the cell cycle are chromosomes visible?
Only during cell division
What is a tumor?
a mass of cancer cells
The two main stages of cell division are called?
mitosis and cytokinesis
Compared to small cells, large cells have more trouble
moving materials in and out
Cancer affects
multicellular organisms
The rate at which wastes are produced by a cell partially depends on the cell's
Volume
True or False- As a cells size increases, it places more demands on its ¨DNA¨.
True
True or False- Normal cells ¨stop growing¨ when they come into contact with other cells.
True
True or False- Proteins called cyclins help regulate the cell cycle.
True
True or False- ¨Cancer¨ is a disorder in which some of the body´s cells lose the ability to control growth and division.
True
Cancer cells from masses of cells is called what?
Tumors
If the surface area of a cell increases 100 times, its volume increases about
1000
The structure labeled A in the figure is called the?
A centromere
True or False- As a cells size increases, its ratio of surface area to volume ¨increases¨.
False, Decreases
True or False- Most of a cells growth takes place during the ¨G2¨ phase of the cell cycle.
False, G1
True or False- The structure shown in the figure is a ¨replicated chromosome.¨
False, Human chromosome
True or False- The ¨smaller¨ a cell, the more difficult is it for the cell to move enough materials across its cell membrane.
False, Larger
Which pair is correct? a. G1 phase, DNA replication b. G2 phase, preparation for mitosis c. S phase, cell division d. M phase, cell growth
B- G2 phase, preparation for mitosis
The process by which cell divides into two daughter cells is called?
Cell division
Which of the following is NOT a way that cell division solves the problem of cell growth?
Cell division increases the mass of the original cell.
Cells grown in a petri dish tend to divide until they form a thin layer covering the bottom of the dish. If cells are removed from the middle of the dish, the cells bordering the open space will begin dividing until they have filled the empty space. What does this experiment show?
Cell inhibition
One difference between cell division in plant cells and in animal cells is that plant cells have
Cell plate
If a cell's DNA were not copied before cell division, the cell could
Could not divide
In eukaryotic cells, the timing of the cell cycle is regulated by?
Cyclins
Cell division is represented in figure 10-1 by the letter
D
What happens when a cell divides?
Each daughter cell receives its own copy of the parent cell's DNA
True or False- Cell division solves the problem of cell growth by ¨increasing¨ cell volume.
False decreasing
True or False- A cell's chromosomes are replicated during "interphase".
False during the S phases
True or False- If it takes a cell one hour to undergo mitosis, about ¨50 minutes¨ of time would be spent in prophase.
False, 30 minutes
True or False- Lack of control over ¨mitosis¨ is the cause of all cancers
Flase, Cell cycle
True or False- Typically, the longest phase of mitosis is ¨metaphase.¨
Flase, Prophase
During normal mitotic cell division, a parent cell that has four chromosomes will produce two daughter cells, each containing
Four chromosomes
Interphase consists of what phases?
G1, S, G2
What are the phases of the cell cycle?
G1, S, G2, M
Which events occur during interphase?
G1: size of cell increases, S: duplicates chromosomes and synthesis of DNA, G2: organelles are produced
What will stop normal cells from growing?
Growth inhibition or contact with other cells
During which phases of mitosis are structures like the one shown in Figure 10-2 visible?
Prophase & Metaphase
What are the phases of mitosis in their proper sequence?
Prophase, Metaphase, Anaphase, Telophase
When during the cell cycle is DNA replicated?
S phase
The structures labeled B in the figure is called?
Sister chromatids
Which of the following is NOT a correct statement about the events of the cell cycle.
The cell grows during the G2 phase
What happens when cells come in contact with other cells?
They stop growing
True or False- A cell splits into two daughter cells during telophase.
True
True or False- An imaginary cubic cell with a side length of 10 mm would have a ratio of surface area to volume of ¨6 : 10.¨
True
Which of the following explains why normal cells grown in a petri dish tend to stop growing once they have covered the bottom of the dish.
contact with other cells stop cell growth
What is an internal regulator of the cell cycle?
cyclin
As a cell becomes larger, its volume?
increases faster than its surface area
A cell with a defective p53 gene is likely to
stop responding to growth regulators
