Bio 127 test 2

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