biology chapter 11
A cell that has 10 chromosomes in the G1 phase will have ______ chromatids in the G2 phase.
20
during normal mitotic cell division a parent cell that has eight chromosomes will produce two daughter cells, each containing...
8 chromosomes
distinguish between chromatids and chromatin
Chromatids: two identical DNA strands joined by a centromere Chromatin: the material that makes up chromosomes (DNA & protein)
what are the 4 steps of the cell cycle. describe what happens in each event.
G1 phase- cell grows larger S phase- cell makes new DNA for daughter cell G2 phase- cell makes new organelles for daughter cell mitosis- cell division (prophase, metaphase, anaphase, telophase)
the process by which a cell divides into two daughter cells is called...
cell division
which event occurs during interphase?
cell grows, replicated DNA for daughter cell, makes organelles for daughter cells (g1, s, g2)
One difference between cell division in plant cells and in animal cells is that plant cells have _____ while animal cells have ____
cell plate ; cleavage
the "X" shaped figure inside the nucleus is called a _____. the center of this structure is called the _____. the two "V" shaped objects that connect in the center are called ______
chromosome ; centromere ; sister chromatids
the process by which a cell divides into two daughter cells is called
cytokinesis
the two main stages of cell division are called...
cytokinesis ; mitosis
(honors) assume that prophase begins with twelve chromatids in the nucleus of a cell. when telophase ends, how many chromosomes will be present in each new nucleus? explain your answer. (numbers in question may be different on the exam).
each nucleus will have six chromosomes. twelve chromosomes is equivalent to six chromosomes since one chromosome is made of two chromatids. each of these six chromosomes will be an exact copy of the parent cell's DNA. when the cell divides, it takes each chromosome and replicates it in the S phase. this allows each replicated cell to have the same amount of chromosomes
When during the cell cycle are chromosomes visible?
only during cell division
during which phase(s) of mitosis are "X" shaped structures visible?
prophase, metaphase
list the phases of mitosis in their proper sequence.
prophase, metaphase, anaphase, telophase
list the 4 stages of mitosis. describe what happens during each of the 4 stages
prophase- the chromatin condenses into chromosomes. the centrioles separate (in animal cells); spindles form. the nuclear membrane and nucleolus break down metaphase- the chromosomes line up across the midline of the cell each chromosome is attached to a spindle fiber at the centromere anaphase- sister chromatids separate into individual chromosomes. they form the classic shape of a "V" as they move towards opposite poles telophase- chromosomes reach opposite sides of the dividing cell. the spindle breaks down. two new nuclear envelopes and nucleoli re-form. the chromosomes uncoil into chromatin
cyclins are a family of closely related proteins that...
regulate the cell cycle
the cell cycle is....
series of events that cells go through as they grow and divide
during metaphase, each chromosome is connected to a (an) ____ and its centromere
spindle
a cell with a defective p53 gene is likely to
stop responding to growth regulators
(honors) describe how the cell cycle is regulated
the cell cycle is regulated by internal regulators and external regulators. internal regulators make sure the cell doesn't go into mitoses until all of the DNA has been replicated. external regulators direct the cells to speed up or slow down the cell cycle. growth factors are external regulators that stimulate the growth and division of cells
what happens when cells come into contact with each other?
the cells will stop growing and dividing
you will complete a paragraph about the cell cycle by filling in the blanks. to do this correctly, you must know the structure names, the stage names in order and what happens in each stage
the eukaryotic cell cycle has two main parts, interphase and mitosis. before dividing the cells must prepare. this preparation is known as interphase. there are three phases of interphase, G1, S, and G2. during the G1 phase, the cell grows larger. during the S phase, the cell makes new DNA for the daughter cell. and lastly, during the G2 phase, the cell makes new organelles for the daughter cell. once interphase has been completed, cell division can begin, this process is also known as mitosis. there are four stages of mitosis, prophase, metaphase, anaphase, and telophase. in prophase, the chromatin condenses into chromosomes and the nuclear envelope and membrane disintegrate. during metaphase, the chromosomes line up in the middle of the cell and each chromosome is attached to a spindle fiver at the centromere. during anaphase, the chromatids separate into individual chromosomes as they move to opposite poles of the cell. in the last phase, telophase, the chromosomes reach opposite sides pf the dividing cell. the spindles break down and a new nuclear envelope and nucleoli re-form. the chromosomes then unwind into chromatin. once mitosis is finished, the cycle starts over again until the cells run out of room to replicate.
what is the role of the spindle during mitosis?
the spindle fibers help separate the chromosomes
Cancer is a disorder in which some cells have lost the ability to control their...
growth
describe how a plant cell produces a new cell wall during cytokinesis
in plants, a cell plate is formed during cytokinesis in between each new nuclei. this plate is formed by a fusion of vesicles from the Golgi complex. after this, each cell forms its own cell wall by laying down cellulose and other polysaccharides.
together, the G1 phase, S phase and G2 phase are called...
interphase
during which phase of mitosis do the chromosomes line up along the middle of the dividing cell?
metaphase
Compared to small cells, large cells have more trouble...
moving needed materials in and waste products out
as a cell becomes larger, what happens to the volume and the surface area?
the volume increases faster than the surface area
cancer cells form masses of cells called
tumors
if the length of a cell increases 3 times, its volume increases about....
27x
When during the cell cycle is a cell's DNA replicated?
s phase
