TEST TWO Various Questions 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
The first level of DNA organization in a eukaryotic cell is
maintained by which molecule?
Histones
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
Attachment of the mitotic spindle fibers to the
kinetochores is a characteristic of which stage of
mitosis?
Metaphase
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
- The fusing of Golgi vesicles at the metaphase plate of
dividing plant cells forms what structure?
Cell plate
At which of the cell-cycle checkpoints do external forces
have the greatest influence?
G1
What is the main prerequisite for clearance at the G2
checkpoint?
Accurate and complete DNA replication
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)
Many of the negative regulator proteins of the cell cycle
were discovered in what type of cells?
cancer cells
Which negative regulatory molecule can trigger cell
suicide (apoptosis) if vital cell cycle events do not occur?
p53
__________ 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
A mutated gene that codes for an altered version of Cdk
that is active in the absence of cyclin is a(n) _____.
oncogene