Module 4 Cell Growth, Reproduction, and Heredity Flashcards
A diploid cell has _______ the number of chromosomes as a haploid cell.
twice
An organism’s traits are determined by the specific combination of inherited _____.
genes
Identical copies of chromatin held together by cohesin at the centromere are called _____.
sister chromatids
Chromosomes are duplicated during what stage of the cell cycle?
S phase
The mitotic spindles arise from which cell structure?
centrosome
Unpacking of chromosomes and the formation of a new nuclear envelope is a characteristic of which stage of mitosis?
telophase
Many of the negative regulator proteins of the cell cycle were discovered in what type of cells?
cancer cells
_______ are changes to the order of nucleotides in a segment of DNA that codes for a protein.
gene mutations
A gene that codes for a positive cell-cycle regulator is called a(n)…
proto-oncogene
The crossover events are the second source of genetic variation produced by meiosis.
false
Meiosis is the nuclear division that forms diploid cells.
false
In metaphase I, the microtubules pull the linked chromosomes apart.
false
Meiosis usually produces ________ daughter cells.
four haploid
During meiosis II, the sister chromatids within the two daughter cells separate, forming six new haploid gametes.
false
Sexual reproduction requires fertilization, a union of four cells from two individual organisms.
false
A diploid, multicellular life-cycle stage that gives rise to haploid cells by meiosis is called a ________.
sporophyte
Germ cells are specialized cells that produce gametes.
true
A ___________occurs when a chromosome segment dissociates and reattaches to a different, nonhomologous chromosome.
translocation
The number and appearance of chromosomes including length, banding pattern, and centromere position is called __________.
karyotype
The gain of an extraneous chromosome is called __________.
trisomy
An organism with more than the correct number of chromosome sets (not just an extra chromosome) is called __________.
polyploid
The first level of DNA organization in a eukaryotic cell is maintained by which molecule?
histone
Which eukaryotic cell-cycle event is missing in binary fission?
karyokinesis
FtsZ proteins direct the formation of a _______ that will eventually form the new cell walls of the daughter cells
septum
Name the processes that eukaryotic cell division and binary fission have in common.
DNA duplication, segregation of duplicated chromosomes, and division of the cytoplasmic contents
The formation of what structure, that will eventually form the new cell walls of the daughter cells, is directed by FtsZ?
septum
Which of the following events does not occur during some stages of interphase?
separation of sister chromatids
Attachment of the mitotic spindle fibers to the kinetochores is a characteristic of which stage of mitosis?
prometaphase
Separation of the sister chromatids is a characteristic of which stage of mitosis?
anaphase
The chromosomes become visible under a light microscope during which stage of mitosis?
prophase
What structure is formed when the Golgi vesicles fuse at the metaphase plate of dividing plant cells?
cell plate
At which of the cell-cycle checkpoints do external forces have the greatest influence?
G1 checkpoint
If the M checkpoint is not cleared, what stage of mitosis will be blocked?
anaphase
Which protein is a positive regulator that phosphorylates other proteins when activated?
cyclin-dependent kinase (Cdk)
Which negative regulatory molecule can trigger cell suicide (apoptosis) if vital cell cycle events do not occur?
p53
Which molecule is a Cdk inhibitor that is controlled by p53?
p21