test 5 Flashcards
What is the basic definition of binary fission?
Divides Bacterial Cells in Two (bacterial cell division)
Which statement is false regarding the genome (genetic material) characteristics of prokaryotes (bacteria)?
Single circular DNA molecule, in a region of cytoplasm called nucleoid
Which statement does not accurately describe the process of binary fission?
Replication, elongation, DNA strand movement, septum formation, FtsZ, daughter cells
Which eukaryotic kingdom of organisms have the most chromosomes on average per individual?
Plants
How many chromosomes do humans have within their normal body cells?
46
If someone is considered monosomy regarding their chromosomes, what does that mean?
They only have 45 chromosomes, have one less chromosome
If someone is considered trisomy regarding their chromosomes, what does that mean?
They have one more chromosome, 47 chromosomes
- What is the one main difference between chromosomes and chromatin? (we covered this before on prior tests and in class)
chromosomes are made of chromatin. Chromatin consists of DNA and protein
Regarding chromosome and chromatin structures, within the ————-, every 200 nucleotides, the DNA duplex is coiled around a core of eight histone proteins. Fill in the blank.
nucleosome
What is a karyotype?
An image of all your chromosomes, chromosomes are stained and visible
Regarding chromosome and chromatin structures, a string of nucleosomes wrap into higher-order coils called ———. Fill in the blank.
solenoids
According to the video Chromosomes and Karyotypes, why are chromosomes packed so tightly? (there are two reasons, know both of them)
DNA has to fit inside a nucleus, wanting to make more cells like the process of mitosis
According to the video Chromosomes and Karyotypes, chromosomes are bound in a region called the ——–. Fill in the blank.
centromere
According to the video Chromosomes and Karyotypes, during what phase of mitosis are karyotypes stained and observed? Why?
Metaphase, chromosomes are condensed and thick
According to the video Chromosomes and Karyotypes, twenty-two pairs of your chromosomes are called autosomes. What does this mean?
Means they are not related to your biological sex
According to the video Chromosomes and Karyotypes, the last pair of chromosomes (pair twenty-three) are called sex chromosomes. What does them mean? How are males and females sex chromosomes different?
They determine biological sex, females = 2 X chromosomes, males= X, Y chromosome
What is the difference between the terms haploid and diploid?
Haploid- sperm cells, only 1 set of chromosomes, diploid- egg cell, only 1 set of chromosomes
What does the term homologous mean regarding chromosomes?
About same size and contain same types of genes
During interphase, after the replication of the chromosomes occurs, each chromosome now consist of ————————- before mitosis begins. Fill in the blank.
two sister chromatids
Sister chromatids are attached together at the ———-, which is the condensed area of the chromosome. Fill in the blank.
centromere
- Which statement describes what occurs during the 𝐺1 stage of interphase?
growth
Which statement describes what occurs during the S stage of interphase?
Cell replicates its DNA “synthesis” (to make something) =s phase
Which statement does not describes what occurs during the 𝐺2stage of interphase?
Condensation in preparation for mitosis
- Which statement does not describe the basic overview steps of mitosis we discussed on chapter ten slide fourteen?
-Microtubules Apparatus Assembles
-Chromosomes line up
-Spindles binds on the Chromosomes
-Sister chromatids are moved apart
Which is not a stage (phase) of mitosis?
P: prophase
M: metaphase
A: anaphase
T: telophase
What is the simple definition of cytokinesis which takes place at the end of mitosis?
Splitting of the cytoplasm
Interphase and mitosis can take twenty-four hours to years to complete the cycle depending on the type of cell. The ——– phase is when the DNA replication is in a resting state (most cells are usually in this state). Fill in the blank.
G0
According to the video Mitosis – The Amazing Cell Process that Uses Division to Multiply, during the cell cycle, ninety-percent of the time the cell is completing ——— and ten-percent of the time ———-. Fill in the blanks.
interphase, mitosis
During the 𝐺2stage of interphase, where do the microtubules begin to attach to on a sister chromatid?
kinetochores
During the 𝐺2stage of interphase, centrioles start to be produced. What is their general function once mitosis begins?
help move the chromosomes to different poles of the cell
Which statement does not describe what occurs during the metaphase stage of mitosis? (know everything in detail we discussed on chapter ten slide twenty)
Chromosomes are lined up single file in the middle, there is an imaginary perpendicular line called the metaphase plate.
What takes place for you to officially know that the stage of metaphase of mitosis has now turned into anaphase of mitosis?
the second the chromosomes begin to be pulled apart and move from the equator anaphase begins, the homologous pairs begin to pull apart
Which statement does not describe what occurs during the anaphase stage of mitosis? (know everything in detail we discussed on chapter ten slide twenty-one)
Chromatids begin to separate. They are moving from the equator to opposite poles of the cell. All homologous pairs are separated. Microtubules get recycled after being removed from the kinetochores Microtubules get shorter and disintegrate for other stuff, however they don’t last long, but they are in constant flux. Chromatids go to opposite ends.
What takes place for you to officially know that the stage of anaphase of mitosis has now turned into telophase of mitosis?
you have separation, and would have 46 positively on each side, finished getting pulled to both sides
Which statement does not describe what occurs during the telophase stage of mitosis? (know everything in detail we discussed on chapter ten slide twenty-two)
A cell plate will begin to form, not actin filament (for animal cells). Remember this helps the separation. They are in tight bundles at the poles of the cell. Really what’s occurring is the opposite of prophase
Telophase ( polar opposite of prophase)
cytoskeleton construction
Kinetochores disappears
Nuclear envelope formation
Chromosomes uncoil —> turn back to chromatid
Nucleolus reappears/ reform
Which statement accurately describes the end product of mitosis?
2 cells
Why do plant cells not use actin to separate their cells at the end of telophase (during cytokinesis)?
actin filaments will not work
According to the video The Cell Cycle and Cancer, what can be a basic definition of cancer?
cells that divide too frequently
According to the video The Cell Cycle and Cancer, what occurs during the 𝐺1/S checkpoint (what is the cell checking for)?
“is the cell growing well enough?” “is its DNA damaged?”
According to the video The Cell Cycle and Cancer, what occurs during the 𝐺2/M checkpoint (what is the cell checking for)?
Checks if DNA was replicated correctly back in S phase; is it growing well enough? Does it have resources needed to continue?
According to the video The Cell Cycle and Cancer, what occurs during the spindle (M) checkpoint (what is the cell checking for)?
Makes sure that chromosomes are correctly lined up in the middle and attached to spindle correctly
According to the video The Cell Cycle and Cancer, what happens when a cell does not meet a requirement of any cell cycle checkpoint?
if the reason the cell can’t go past the checkpoint is a reason that can be fixed, the cell may kind of pause here until it can fix the issue.
But if it can’t be fixed? Then the cell does something called apoptosis which basically means the cell self destructs This ensures that a cell that is damaged beyond repair will not go on to divide.
According to the video The Cell Cycle and Cancer, what (or which component of a cell) is regulating mitosis?
proteins
According to the video The Cell Cycle and Cancer, what is the negative regular p53 responsible for?
initiating apoptosis
Which statement describes an irreversible step of the cell cycle once it begins (and the reason we have checkpoints)?
regulate and create your DNA from 46 to 92, not lined up properly, or split you sister chromatids correctly
The 𝐺1/S cell division checkpoint is the point during which —————– (positive regulatory signals which are proteins that stimulate cell division) affect the cell cycle. For example, ———- initiates an amplifying chain of internal cell signals that stimulate cell division. Fill in the blanks.
growth factors, PDGF
What is the function of our p53 gene regarding the cell cycle?
is a negative regulatory signal, if something goes wrong, this says to destroy it(apoptosis); tumor suppressor gene, and DNA monitor(if there is damage it says to repair it)
What can happen to your cell cycle if (a) one copy or (b) both copies of your p53 gene is absent or damage beyond use?
A . one copy of p53 - as long as you have one copy of the gene then it is ok, but you are more susceptible to cancer
B. p53 absent - there is nothing to regulate the process and therefore cancer would begin to develop
What is the (a) definition or (b) function of proto-oncogenes?
Proto-oncogenes - (a) a cell that is precancerous, your cell can slowly become a cancer cell: (B) promotes cyclin CDKs to function
What can occur within your cell cycle if one mutant copy of a proto-oncogene becomes present?
normal cellular genes that become [oncogenes] when mutated can become a cancerous cell
What is the (a) definition or (b) function of tumor-suppressing genes?
A. tumor suppressor - normally act to inhibit the cell cycle
B tumor suppressor - to suppress tumors
According to the video Why We Haven’t Cured Cancer, what is the basic reason we have not simply found a “magic bullet” to curing all types of cancer?
each tumor develops differently and can originate in any type of tissue
According to the video Why We Haven’t Cured Cancer, what is the one thing all cancers have in common?
uncontrolled cell division
According to the video Why We Haven’t Cured Cancer, why might most cancer drugs not work for all patients with the same type of cancer?
There can be thousands of possible combinations of mutations, so every single tumor will follow a different genetic path.
Which statement describes the research completed by Pierre-Joseph van Beneden (in 1887) that lead to a new biological discovery?
found chromosomes in different types of cell (haploid-1 set of chromosomes, diploid-2 sets of chromosomes), led to mendel figuring the rest out
Meiosis involves the production of ——————(for example eggs and sperm) and mitosis involves the production of ——————– (i.e. body cells). Fill in the blanks.
haploids, gametes diploid, somatic
During the process of sexual reproduction, egg and sperm fuse to produce a single cell called a ———–. Fill in the blank.
zygote
Why is meiosis called reduction division?
because after you’ve doubled up your genetic material then it changes when you reduced this you go from 46 —> 23
What is a difference between sexual and asexual reproduction
Sexual reproduction - gametes are involved
Asexual reproduction - gametes are not involved (budding, fission, cloning)
In humans, how many chromosomes are found within somatic cells and how many chromosomes are found within gametes?
Somatic- 46 chromosomes
Gametes- 23 chromosomes
How do germ line cells and somatic cells differ?
Germ line cells - the interphase process only happens in germ line cells(diploids), but produces something that is haploid
Somatic cells - Body cells
According to the video The Cell Cycle and Cancer, which statement does not describe a reason a cell can become cancerous?
Might not be able to communicate with other healthy cells, might not be able to carry out normal cell functions, may not securely anchor themselves like other cells do (more likely to travel somewhere else)
OR
Genetics, toxins, radiation, UV light
According to the video Why We Haven’t Cured Cancer, even with the new discoveries in medicine, why can we not have personalized medicine currently?
scientists have to come up with more effective ways to test drugs and figure out how to use them in people
The fusion of gametes (one egg and one sperm) to form a new cell is called —————– (i.e. fertilization). Fill in the blank.
syngamy
——– occurs during meiosis and is when homologous chromosomes find each other and become closely associated. Fill in the blank.
synapsis
—— ———– occurs during meiosis and is when genetic recombination and the exchange of chromosomal material (i.e. DNA) takes place.
crossing over
What is the difference between a chiasmata and chiasma?
Chiasmata- site of crossing over between genetic material
Chiasma- evidence of crossover over can often be seen under a light microscope as an x-shaped structure
How is interphase taking place before meiosis and interphase taking place before mitosis different?
THERE IS NOTHING DIFFERENT BETWEEN THE TWO
According to the video Mitosis and Meiosis Side by Side Comparison, do you start with haploid and/or diploid cells during mitosis and meiosis?
diploid
Which statement does not describe what occurs during the prophase I stage of meiosis?
Chromosomes condense and thicken, line up with homologous pairs, the process of crossing over
According to the video Mitosis and Meiosis Side by Side Comparison, which statement accurately describes either a (a) similarity or (b) difference between prophase of mitosis and prophase I of meiosis?
A. Everything but one thing
B. Difference: synapsis and crossing over occurs
Which statement does not describe what occurs during the metaphase I stage of meiosis?
Chromosomes in middle of cell, in pairs in the middle
According to the video Mitosis and Meiosis Side by Side Comparison, which statement accurately describes either a (a) similarity or (b) difference between metaphase of mitosis and metaphase I of meiosis?
A. Both the chromosomes are going to line up in the middle
B. For mitosis, the chromosomes line up in a single file line while in Meiosis they’re still going to be in pairs
Which statement does not describe what occurs during the anaphase I stage of meiosis?
A. The chromosomes are being pulled away to opposite sides of the cell
According to the video Mitosis and Meiosis Side by Side Comparison, which statement accurately describes either a (a) similarity or (b) difference between anaphase of mitosis and anaphase I of meiosis?
mitosis-chromatids are being pulled away because of spindles, moving to opposite sides of the cell
Meiosis- same thing but its chromosomes (not chromatids) being pulled away to opposite sides of cell
Which statement does not describe what occurs during the telophase I stage of meiosis?
A. The chromosomes are at the complete opposite ends and new nuclei are forming on each side (make two new cells)
B. The nuclei surround the chromosomes on both sides
C. Cytokinesis follows to split the cytoplasm to complete the actual dividing
D. They end up with two identical diploid cells
According to the video Mitosis and Meiosis Side by Side Comparison, which statement accurately describes either a (a) similarity or (b) difference between telophase of mitosis and telophase I of meiosis?
The chromosomes are at the complete opposite ends and new nuclei are forming on each side to make these two new cells. And they are starting to surround the chromosomes on both sides as this will eventually form 2 cells. Cytokinesis follows to split the cytoplasm to complete the actual dividing of the cell. So at the end of mitosis and cytokinesis, we end with two identical, diploid cells.
Which statement describes what occurs during the prophase II stage of meiosis?
Chromosomes condensing in both of the two cells.
Which statement describes what occurs during the metaphase II stage of meiosis?
M for middle, this time the chromosomes are in a single file line and looks similar to metaphase in mitosis
Which statement describes what occurs during the anaphase II stage of meiosis?
The chromatids are being pulled away from each other and going to opposite sides of the cell
Which statement describes what occurs during the telophase II stage of meiosis?
Chromosomes are at the complete ends and new nuclei are forming on each side to make new cells
Which statement describes the final results of meiosis described in class on chapter eleven slide sixteen?
Cytokinesis will follow meiosis II to completely split the cytoplasm and you will end up with 4 daughter cells from the two that were spit, haploid sets, and no two cells are alike, they are gametes
According to the video Mitosis and Meiosis Side by Side Comparison, what are the end results after the end of the second cytokinesis during meiosis II? How does this compared again to the end products of mitosis?
A. After the second kinesis during meiosis II there are a total of 4 daughter cells
B. Compared to the end products of mitosis they are similar because they spilted cells through cytokinesis, the cells for mitosis are body cells and the ones for meiosis are sex cells
Why are the gametes produced at the end of meiosis I and II not genetically the same when compared to the original “parent” cell?
They are not genetically the same because they are sex cells (sperm and female) and cant be the same
Which statement describes a general difference between the processes of mitosis and meiosis (know the table on chapter eleven slide 17)?
MITOSIS- DNA replication occurs during interphase before nuclear division begins, 1 division including PMAT, no synapsis of homologous pairs, two daughter cells each diploid and genetically identical to the parent cell, role in the animal body is to enable a multicellular adult to arise from a zygote; produces cells for growth and tissue repair
MEIOSIS- DNA replication occurs once during interphase before meiosis 1 begins, 2 divisions each including PMAT, synapsis is unique to meiosis, four daughter cells each haploid containing half as many chromosomes as parent cell; genetically nonidentical to parent cell and each other, role in the animal body is to produce gametes, reduce chromosome number by half and introduces genetic variability among the gametes
How can cytokinesis (and mitosis in general) differ in fungi and protists compared to plant and animal cells (we discussed a few ways in class on the chapter ten slide twenty-four)?
Fungi: Their entire process of mitosis happens exclusively inside the nucleus. The envelope does not dissolve until the end of mitosis, and that’s when they split.
Protists: There are so many ways to do it there is no one way.
What is the difference between the plant and animal prophase stage of mitosis (we discussed one main difference)?
Aster formation does not occur in the plant process of prophase.
