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What is 1 + 3?
Proteins with positive charges that are wrapped around DNA within chromosomes are:
Identical copies of each chromosome are called __________________ and are joined at the
C. sister chromatids; centromere
Cell growth is assessed at the G1 checkpoint.
B. DNA replication is assessed at the G2 checkpoint.
C. Mitosis is assessed at the M checkpoint
What cell cycle regulatory protein is a tumor-suppressor protein?
Most eukaryotes have between ___________ chromosomes in their body cells
B. 10 and 50
13. During which stage of mitosis do replicated chromosomes condense and the nuclear
The spindle is:
the network of protein cables that will pull the chromatids to opposite ends of the cell
You look in the microscope and see sister chromatids moving to opposite sides of the cell.
You conclude the cell is in:
19. If cell division is no longer possible, eukaryotes can arrest the cell cycle. During which
stage is this decision made?
20. During which stage of the cell cycle does the M checkpoint occur
What is the goal of angiogenesis inhibitors?
They inhibit the formation of small blood vessels that feed a tumor
What is telomerase?
An enzyme that adds bases back to the tip of chromosomes every time a cell divides
After duplication, sister chromatids remain joined together:
by the centromere
30. Which is not correct about the way prokaryotes divide?
C. The replication of DNA occurs in one direction around the circle.
The pairing of homologous chromosomes
is called synapsis
What is the basis of Herman Muller's Ratchet theory
That once harmful mutations arise, asexual populations have no way of eliminating them.
The purpose of meiosis I is:
to separate homologous chromosomes
In humans, gametes are _______, while somatic cells are ________.
Which scientist is credited with proposing in 1887 that an egg and a sperm fuse to form a
E. van Beneden
Which is incorrect about meiosis?
C. Sister chomatids separate in anaphase I.
Independent assortment of homologous chromosomes occurs at:
B. metaphase I
In humans, _____________ divide by meiosis to produce eggs and sperm.
. germ-line cells
During which stage do chromosomes line up in single file on the equatorial plane?
C. Metaphase II
During which stage do chromosomes line up in pairs on the equatorial plane?
The main difference between prophase I and II is that in prophase I:
synapsis and crossing over occurs
In humans, how many different kinds of gametes can be produced due to independent
Animals do which type of reproduction?
C. Sexual and asexual
The random orientation of different pairs of homologous chromosomes on the metaphase
plate is responsible for __________.
After meiosis, the gamete joins with another gamete in all eukaryotic organisms.
Meiosis involves four nuclear divisions.
The development of an adult from an unfertilized egg is called ___________.
During metaphase I of meiosis, homologous chromosomes can orient themselves such that
one or the other will by chance go to a particular daughter cell in a process known as
When a gene is carried on one of the sex chromosomes, it is said to be
Put the following terms in the correct order from start to finish
chromosome → gene → primary transcript → messenger RNA → polypeptide → protein
The gene for ABO blood type encodes an enzyme that adds sugar molecules to lipids on
the surface of red blood cells.
What discovery by T. H. Morgan finally determined that genes were carried on
B. Sex-linked inheritance of eye color in fruit flies