Surface-area-to-volume ratios indicate
as cells get larger, their surface area gets larger but at a slower rate than the volume increases.
Compared with a eukaryotic cell, a prokaryotic cell
lacks organelles beyond ribosomes.
Circulating red blood cells in your body do not contain a nucleus and other organelles. Are these cells living?
Yes, because they are actively metabolizing and once contained organelles.
Which of the following is a prokaryotic cell?
bacterium
In moving from the outside environment to the inside of a bacterium, the first layer encountered would be
the capsule.
A researcher samples the waters of the boiling hot springs in Yellowstone National Park. Under the microscope, she observes what appear to be living cells in the water. If these indeed are living cells, what type of cell would they most likely be?
prokaryotic, archaea
Within eukaryotic cells, the ________ is surrounded by a double membrane and carries the coding that determines protein synthesis.
nucleus
Which nuclear structure(s) contain(s) the hereditary material?
chromatin
Nucleolus
contains RNA and is found in the nucleus
Which of the following structures are NOT found in the cytoplasm?
chromosomes
Which eukaryotic organelle is the largest?
nucleus
Ribosomal RNA is produced in the
nucleolus
Which cellular structure is responsible for packaging materials with the cell?
Golgi apparatus
Proteins are processed and modified in the interior of the
rough endoplasmic reticulum.
If an active cell produces an important protein for secretion, what is the correct sequence of organelles that are involved in the production of the protein?
ribosomes-to-endoplasmic reticulum-to-Golgi apparatus
The ________ will store pigments and toxins in plant cells.
vacuole
When a lysosome fuses with a vacuole,
its contents are digested.
Tay-Sachs is a serious childhood metabolic disorder where ________ fail to digest certain lipids.
lysosomes
Which organelle primarily functions to package or regulate the production of H2O2?
peroxisome
Which of the following would not be a function of the peroxisomes?
store toxic materials in the cell
The failure of which organelle during development can result in a child being born with webbed toes?
lysosomes
Cellular respiration is best associated with the
mitochondrion.
Both plant and animal cells have mitochondria because they both
need ATP for energy.
The "powerhouse" of the cell is the
mitochondria
In plants, chloroplasts are necessary for
photosynthesis
Which of these is present in plant, but not animal, cells?
chloroplasts
Thylakoids and cristae are, respectively, structures of
chloroplasts and mitochondria.
Which organelle will give off oxygen and use up carbon dioxide in plants?
chloroplast
When viewed through a microscope, one characteristic of living cells is that their internal structures move. What organelles are most directly responsible for this motion we see?
mitochondria and cytoskeleton
Which organelle has 13 rows of tubulin dimers around an empty central core?
microtubules
Which organelle has a 9 + 0 pattern of microtubules?
centriole
Which of these is mismatched?
mitochondria-stroma
The mitotic stage of cell division consists of
mitosis and cytokinesis.
The cell cycle consists of
mitosis and interphase
Following a cut or scrape, which process repairs your skin?
mitosis
Which is NOT a correct association?
interphase-shortest stage of the cell cycle
The only function of apoptosis is to destroy healthy cells when they become damaged or infected.
False
Which of the following is the correct sequence for the cell cycle?
S-G2 -M-G1
During interphase
hereditary material duplicates itself.
Upon examination, a cell is found to have twice as much DNA as the normal diploid state but is no longer in the process of replicating the DNA. All of the DNA is found within a single nucleus. Which stage of the cell cycle is this cell in?
G2 phase
During which stage of the cell cycle do the chromosomes duplicate?
interphase
Which of the following best characterizes apoptosis?
Apoptosis plays a normal role in development and cancer prevention.
Which of the following is not true concerning the checkpoints in the cell cycle?
The first checkpoint is located in the S phase of interphase.
If a cell stops at the G1 checkpoint, this is most likely due to what problem?
There is DNA damage.
Which type of genes, when abnormally activated so that protein is always present and active, can result in cancer?
proto-oncogenes
Eukaryotic chromosomes are composed of
chromatin
Which is NOT a correct association?
mitosis-when a cell duplicates and then divides twice to reduce chromosome number by half
In humans, the diploid number of chromosomes is
46
The chromatids are held together at a region called the centromere.
True
If the total number of chromosomes in a cell is six, then after mitosis there will be
six chromosomes in each daughter cell.
If a crayfish has 200 total chromosomes in its body cells (not ovaries or testes),
they would consist of 100 pairs with one of each pair from the father, one of each pair from the mother.
Which of the following are genetically identical?
sister chromatids
During what stage of mitosis does the nuclear envelope disappear and the chromosomes become distinct?
prophase
Which sequence of stages in mitosis is correct?
prophase, metaphase, anaphase, telophase
In which stage of mitosis do the chromosomes line up in the center of the cell?
prophase
During which phases of the cell cycle do the chromosomes look like Xs?
prophase, metaphase
The nuclear membrane reappears in mitosis during
telophase
In plant cells, what is responsible for organizing the spindle?
centrosomes
How does cell division differ between animal and plant cells?
The cell plate is the final partitioning of plant cells.
What forms the contractile ring in animal cells?
actin filaments
Meiosis results in a change in chromosome number indicated by
2n to n.
If the diploid chromosome number is 16, the chromosome number of each gamete will be
8
An organism has 8 pairs of chromosomes. If the sperm and egg did not undergo meiosis, how many chromosomes would be present in a cell that resulted from the fusion of a sperm and egg?
32
Synapsis occurs during what stage of meiosis?
Prophase I
Without considering the variation provided by crossing-over, how much will two siblings from one set of parents vary from each other?
Two sibling offspring may share with each other from zero to 23 chromosomes
Homologous chromosomes are genetically identical to each other.
False
During crossing-over,
chromatids exchange segments of genetic material.
During what stage do homologous chromosomes separate from each other?
anaphase I
During what stage of meiosis do sister chromatids separate from each other?
anaphase II
You are examining a cell under the microscope and see what appear to be four sister chromatids bound together and remnants of the nuclear envelope. What stage of meiosis are you looking at?
prophase I
You are looking at a cell under the microscope, and see what appears to be several "X" structures being pulled to each side of the cell. What stage of meiosis are you looking at?
anaphase I
The second meiotic division is essentially a mitotic division except for the fact that the cells produced are
haploid
The formation of sperm gametes is termed
spermatogenesis
A basic difference between spermatogenesis and oogenesis is that in oogenesis
one functional egg is produced.
Which of the following statements is NOT true about oogenesis in humans?
Four equal size daughter cells will form.
Which of the following is not a reason why two children born to the same parents (not identical twins) are unlikely to have the same genetic makeup?
Since they are produced at different times, all sperm will be genetically different from all other sperm.
During which phase will homologous chromosomes separate?
anaphase I