TEAS 7 - Science (Cellular Reproduction) Flashcards
___ is the cellular division process where one cell divides to produce two identical daughter cells
Mitosis
Mitosis is the cellular division process where one cell divides to produce ___ ___ daughter cells
two identical
What are the four phases of mitosis?
- prophase
- metaphase
- anaphase
- telophase
What is the stage of the cell cycle that occurs before mitosis begins?
Interphase
___ is important because it is the time when the cell is preparing to divide into two daughter cells.
Interphase
During interphase, the cell ___ in size, produces ____ organelles and proteins, and duplicates all of its DNA.
The cell then has ___ copies of its DNA going into mitosis, which is organized into two sister chromatids as the DNA condenses.
increases
additional
two
A single chromosome is called ____. A duplicated chromosome is called a ____ or sister ____.
chromatid
chromosome
sister chromatids
What is the first stage of mitosis?
prophase
Prophase is the ___ stage of mitosis, where the cell begins the process of dividing into two daughter cells.
first
At the beginning of prophase, the chromatin, which is the combination of DNA and proteins, starts to ___.
This condensation causes the chromatin to coil and compact, resulting in the formation of distinct structures called ___.
Chromosomes are ___ to manage and distribute during cell division.
condense
chromosomes
easier
As the mitotic spindle develops, it interacts with the chromosomes at specialized protein structures called ___ which are formed at the centromere region of each chromosome.
kinetochores
The mitotic spindle is a structure composed of ___ that helps in the movement and separation of chromosomes during cell division.
microtubules
Another process that is happening in prophase is the breakdown of the ___ ___, the membrane that surrounds the nucleus.
nuclear envelope
The nucleus of the cell is surrounded by a membrane called the ___ ___, which separates the nucleus from the rest of the cell.
nuclear envelope
In what region of the chromosome are kinetochores found?
centromere
What is the center region of chromosomes called?
the centromere
Where do spindle fibers attach to align and position the chromosomes in the cell?
the kinetochore
___ is the stage of mitosis where the chromosomes line up in the center of the cell as the cell gets ready to divide.
Metaphase
Metaphase is the next stage of mitosis, where the chromosomes line up in the ___ of the cell as the cell gets ready to divide.
center
During metaphase, spindle fibers continue to exert tension on the chromosomes, aligning them along the ___ ___ in the center of the cell.
This alignment ensures that each chromosome is properly ___ for the upcoming separation.
metaphase plate
positioned
In prophase, two ___, which are small organelles located near the nucleus, move to opposite ends of the cell.
centrosomes
As the centrosomes move, they generate ___ ____ that extend from each centrosome toward the center of the cell. These spindle fibers form a complex network known as the ___ ___.
spindle fibers
mitotic spindle
Why does the nuclear envelope break down during prophase?
this breakdown allows the chromosomes to be exposed to the cytoplasm of the cell
The metaphase plate is an ___ plane that runs through the ___ of the cell and is perpendicular to the spindle fibers. The chromosomes line up in a single file line along this plate.
imaginary
center
The alignment of chromosomes in metaphase is essential for ensuring that each daughter cell receives an ___ and ___ set of chromosomes during cell division.
equal
complete
In anaphase, the spindle fibers ___ and pull the sister chromatids (the two identical parts of a chromosome) apart towards the ___ poles of the cell.
shorten
opposite
In ___, the spindle fibers shorten and pull the sister chromatids (the two identical parts of a chromosome) apart towards the opposite poles of the cell.
anaphase
At the start of anaphase, what happens to the connections holding the sister chromatids together, the centromeres?
they dissolve
Before moving into ___, the cell completes a quick checkpoint to make sure that all the chromosomes are lined up correctly and that all of them are connected to the spindle fibers by their ___.
anaphase
kinetochores
When the centromeres dissolve, it allows the sister chromatids to ___ and become individual chromosomes. Each chromosome now consists of a single ___.
separate
chromatid
Once the sister chromatids have separated, they move toward opposite ___ of the cell. This movement is facilitated by the ___ of the spindle fibers attached to the chromosomes.
poles
shortening
While anaphase is primarily focused on the separation and movement of chromosomes, it also marks the beginning of ___, the division of the cell’s cytoplasm.
cytokinesis
What is cytokineses?
the division of the cell’s cytoplasm
Cytokinesis the division of the cell’s ___.
cytoplasm
As the spindle fibers contract, they pull the chromosomes in the direction of the ___ located at opposite ends of the cell.
centrosomes
In animal cells, a contractile ring composed of actin (___) and myosin proteins forms in the center of the cell. The ring contracts, leading to the formation of a cleavage furrow that eventually ___ the cell into two daughter cells.
microfilaments
pinches
What happens to the spindle fibers during telophase?
they disappear
During ___, the spindle fibers disappear, and a nuclear envelope reforms around each set of chromosomes.
telophase
During telophase, the spindle fibers ___, and a ___ envelope reforms around each set of chromosomes. The chromosomes begin to ___, and the cell begins to ___, creating two identical daughter cells.
disappear
nuclear envelope
uncoil
divide
In telophase, ___ distinct groups of chromosomes are present, one at each pole of the cell.
two
As telophase progresses, the chromosomes begin to decondense or ___. They transition from their highly condensed state back into their extended form of ___.
uncoil
chromatin
Why do chromosomes decondense during telophase?
to allow the genetic material to become accessible for gene expression and other cellular processes
At what stage of mitosis does the nuclear envelope reform around each set of chromosomes?
telophase
The nuclear envelope is made up of two ___ bilayers, and it separates the genetic material from the rest of the cell.
phospholipid bilayers
Within each newly forming nucleus, the ___, which is responsible for producing ribosomes, reappears.
nucleolus
The nucleolus is composed of RNA, proteins, and DNA segments, and it plays a vital role in ___ synthesis.
protein synthesis
Telophase also marks the completion of ___, the process of dividing the cell’s cytoplasm into two daughter cells.
cytokinesis
In animal cells, the contractile ___ formed during anaphase contracts further, forming a ___ furrow that pinches the cell in half.
ring
cleavage
After mitosis, the two daughter cells will continue to grow and carry out their functions, identical to the ___ cell that produced them.
parent
___ is important because it allows cells to divide and produce new, identical, cells for growth and repair, and it also plays a crucial role in asexual reproduction in some organisms.
Mitosis
Which of the following correctly differentiates diploid cells from haploid cells?
There are (2n) number of chromosomes in diploid cells and (n) number of chromosomes in haploid cells.
Which of the following statements is CORRECT about daughter cells formed during mitotic cell division?
Mitosis results in two identical daughter cells to their parent cell.
The process of asexual reproduction when a prokaryotic cell divides to form two identical cells where each has the potential to grow and become an independent cell is called:
Binary fission
Which of the following lists the phases of mitosis in the correct order?
Prophase, Metaphase, Anaphase, Telophase
The process of nuclear division in eukaryotic cells that occurs when a parent cell divides to produce two identical daughter cells is known as:
Mitosis
Humans have 46 chromosomes in each somatic cell. How many chromosomes will be there in each daughter cell that has been formed after mitosis?
46
Is mitosis involved in gamete cells (germ cell formation or division)?
No
*Mitosis occurs in somatic cells; this means that it takes place in all types of cells that are not involved in the production of gametes.
Which of the following is correct about sister chromatids?
Sister chromatids are the two identical copies of a chromosome.
Which of the following statements best describes what happens during prophase?
The nucleolus shrinks and disappears
*Prophase is the first phase of mitosis or cell division. During prophase, the nuclear membrane disappears.
The filaments or thread-like structures that form mitotic spindles and are involved in chromosomal segregation are called:
Spindle fibers
The phase in which the mitotic spindle grows and some of the microtubules start to attach to chromosomes is known as:
Prometaphase
*In the late prophase (sometimes also called prometaphase), the mitotic spindle begins to attach to and organize the chromosomes.
Which of the following is the characteristic of metaphase?
Metaphase plate formation
“Sister chromatids separate from each other and move towards the opposite poles of the cell.”
The above statement best describes which of the following phases of the mitotic cell cycle?
Anaphase
Cytokinesis begins at which phase of the cell cycle?
Anaphase
___ is a cellular division process where one cell divides twice to produce four, haploid daughter cells
Meiosis
___ cells have two sets of chromosomes.
Diploid
___ cells have one set of chromosomes.
Haploid
A ___ is a sex cell that joins with another gamete during fertilization to create a zygote with two sets of chromosomes.
Gamete
___ ___ is the process of homologous chromosomes exchanging segments of their DNA, resulting in genetic variation among offspring.
Crossing over
Meiosis begins with a phase called ___, during which the cell grows, carries out its normal functions, and duplicates its DNA.
interphase
How many phases are there in meiosis?
2
Meiosis consists of two main phases – Meiosis ___ and Meiosis ___.
Meiosis I
Meiosis II
Each phase of meiosis results in ___ cell division.
one
Each phase of meiosis results in ___ cell division, which is why the cells need __ phases in order to divide twice.
one
two
Meiosis I results in ___ daughter cells. Meiosis II results in ___ daughter cells, as each of the daughter cells from Meiosis I divides into another two cells.
2
4
The most significant event in prophase I is ___ ___ pairing. Homologous chromosomes, which are a pair of similar chromosomes (one from each parent), come together and form a structure called a ___.
homologous chromosome
tetrad
In ___, the cell prepares for division. The nuclear membrane starts to break down, and the chromosomes condense and become visible.
Prophase I
Crossing over is a genetic exchange that promotes genetic ___.
diversity
___ is the first phase of meiosis. It begins with one cell that divides into two daughter cells. Each daughter cell has the same number of chromosomes as the original cell.
Meiosis I
What are the stages of Meiosis?
Meiosis I - Prophase I, Metaphase I, Anaphase I, and Telophase I
Meiosis II - Prophase II, Metaphase II, Anaphase II, and Telophase II
What is a tetrad?
During prophase I, a pair of similar chromosomes (a pair from each parent), come together to form a tetrad.
During this pairing of tetrads, sections of the chromosomes may exchange genetic material through a process known as ___ ___. This genetic exchange promotes genetic diversity.
crossing over
In ___, the homologous pairs of chromosomes line up along the center of the cell, called the metaphase plate, and become attached to spindle fibers.
The alignment of chromosomes is random, leading to ___ ___, which further increases genetic diversity.
Metaphase I
independent assortment
In ___, the homologous chromosomes separate and are pulled to opposite poles of the cell by the spindle fibers. The sister chromatids remain attached to each other at their centromeres.
Anaphase I
In ___, the separated homologous chromosomes reach the opposite poles of the cell. The nuclear membrane reforms around each set of chromosomes, and the cell undergoes cytokinesis, resulting in two daughter cells.
Telophase I
In telophase I, each daughter cell has only ___ chromosome from each homologous pair, and each chromosome consists of ___ sister chromatids.
one
two
___ is the second phase of meiosis.
Meiosis II
There is no DNA duplication in the two phases of Meiosis, so the daughter cells have ___ the amount of chromosomes as the original cells.
half
The ___ daughter cells from Meiosis I go through another round of cell division in Meiosis II, creating ___ new daughter cells.
2
4
In ___, the chromosomes align individually along the metaphase plate, attached to spindle fibers.
Metaphase II
The daughter cells of Meiosis II become ___ (sex cells) that have the potential to combine with another gamete to create a ___ set or collection of chromosomes.
gametes
full
In ___, the two daughter cells from meiosis I enter a brief interphase, where no DNA replication occurs. The chromosomes recondense, and the nuclear membrane begins to break down.
Prophase II
In ___, the centromeres divide, separating the sister chromatids. The spindle fibers pull the chromatids to opposite poles of the cell.
Anaphase II
In ___, the chromosomes reach the poles of the cell. Nuclear membranes form around each set of chromosomes, and cytokinesis occurs, resulting in the formation of four haploid daughter cells.
Telophase II
In Telophase II, the chromosomes reach the poles of the cell. ___ ___ form around each set of chromosomes, and ___ occurs, resulting in the formation of ___ haploid daughter cells.
Nuclear membranes
cytokinesis
4
After cytokinesis occurs during Telophase II, the result is 4 (haploid/diploid) daughter cells.
haploid
The four daughter cells produced at the end of ___ are genetically unique due to the ___ assortment of chromosomes in meiosis I and the exchange of genetic material during ___ ___.
Meiosis II
random
crossing over
After cytokinesis occurs during Telophase II, the result is ___ ___ daughter cells.
These cells contain ___ the number of chromosomes as the original cell, and each chromosome consists of only one chromatid.
4 haploid
half
Which of the following is correct about the difference between sexual and asexual reproduction?
In asexual reproduction, diploid parent cells produce diploid daughter cells. Sexual reproduction typically involves the fusion of two haploid (n) gametes (one from each parent), which results in a diploid (2n) zygote. This zygote then develops into a diploid organism.
Which of the following events occurs exclusively during prophase I of meiosis and contributes to genetic diversity in offspring?
Homologous chromosomes exchange segments in a process called crossing over.
The 4 daughter cells produced at the end of meiosis II, serve as ___ (sperm or egg cells) and can combine during ___ to create a new individual with a diverse genetic makeup.
gametes
fertilization
During sexual reproduction, the zygote is formed when a male gamete fuses with a female gamete. How many chromosomes does the zygote cell contain?
2n
*Sexual reproduction typically involves the fusion of two haploid (n) gametes (one from each parent), which results in a diploid (2n) zygote. This zygote then develops into a diploid organism.
Which of the following mechanisms involves the division of a single cell to form cells with half of the original amount of genetic material?
Meiosis
Which of the following lists the phases of meiosis in the correct order?
Prophase I, Metaphase I, Anaphase I, Telophase I, Cytokinesis, Prophase II, Metaphase II, Anaphase II, Telophase II, Cytokinesis
How many chromosomes are in daughter cells produced by meiosis?
23
How many chromosomes are in daughter cells produced by mitosis?
46
“Each chromosome ends up with an identical twin called sister chromatids.”
The above process takes place in which of the following phases of meiosis?
interphase
“Homologous chromosomes line up to the center of the cell.”
This event occurs in which phase of meiosis?
Metaphase I
Which of the following is the function of meiotic cell division?
formation of sex cells or gametes
“Homologous pairs pull apart and move to opposite ends of the cell.”
This event occurs in which of the following phases of meiosis?
Anaphase I
“Chromosomes arrive at opposite poles of the cell and the nuclear membrane reforms.”
This event occurs in which phase of meiosis?
Telophase I
Which of the following is NOT a phase of meiosis?
Interphase
*Interphase is not a phase of meiosis. It is that phase of the cell cycle where the cell grows, duplicates its DNA, and prepares for cell division. Interphase occurs before meiosis begins.
During Prophase II of meiosis, which of the following events happens?
the nuclear membrane starts to break down, and the chromosomes recondense.
Which of the following statements is true about crossing over?
It increases genetic diversity.
Which of the following statements is true about crossing over?
Meiosis I involves crossing over, whereas meiosis II does not.
___ involves the separation of homologous chromosomes, whereas ___ involves the separation of sister chromatids.
Meiosis I
Meiosis II
Which of the following statements is true about homologous chromosomes?
They contain the same genes but may have different alleles.
- This is correct because homologous chromosomes have the same genes at the same loci, but they can have different alleles for those genes, contributing to genetic diversity.
How many daughter cells are produced at the end of meiosis?
4
