Chapter 3 homework Mastering A&P

During which phase of mitosis do the nuclear envelope and nucleoli disappear?

Prophase Correct Prophase is the first phase of mitosis. During this phase, the sister chromatids condense, the nuclear envelope and nucleoli disappear, and the spindle apparatus forms.

What builds new strands of DNA?

DNA polymerase

A primary active transport process is one in which __________.

molecules move through transport proteins that have been activated by ATP

The sodium-potassium pump uses ATP to move sodium and potassium ions across the plasma membrane. This statement describes _____.

primary active transport

During which phase does chromatin condense and become chromosomes?

prophase

During which phase does DNA replication occur?

synthesis, s phase of interphase

Which protein joins together the Okazaki fragments of DNA in the lagging strand?

DNA ligase DNA ligase joins the Okazaki fragments in the lagging strand, turning it into a continuous strand.

Which statement about DNA replication is false?

DNA ligase adds nucleotides to the lagging strand.

A vesicle fuses with the plasma membrane and releases its contents to the extracellular fluid. This statement describes _____.

exocytosis The term exocytosis literally means "out of the cell."

Some transport processes use transport proteins in the plasma membrane, but do not require ATP. This type of transport is known as _____.

facilitated diffusion

The majority of water molecules moving across plasma membranes by osmosis do so via a process that is most similar to ____.

facilitated diffusion

List in correct order the phases of mitosis.

prophase, metaphase, anaphase, telophase

What is the name of the process by which the cytoplasm divides in two?

Cytokinesis Correct During cytokinesis, a ring of actin and myosin filaments contract to form a cleavage furrow and the cell divides in two.

List in correct order the phases of interphase.

G1, S, G2

During which phase of mitosis do sister chromatids line up at the center of the cell?

Metaphase Correct Spindle microtubules from both poles of the cell attach to the sister chromatids and pull them in both directions. During metaphase, the sister chromatids are forced to the center of the cell.

During which phase of mitosis do the sister chromatids move apart?

Anaphase Correct During anaphase, the centromeres split and the spindle microtubules pull the sister chromatids to opposite poles of the cell. The single chromatids are now considered chromosomes.

When a double helix of DNA is replicated, two complete helices are formed. Together, these helices are called sister __________.

Chromatids Correct Each new daughter cell receives one of the sister chromatids. After the chromatids separate, each is considered a new chromosome. At the end of cell division, each new cell contains 23 pairs of chromosomes.

During which phase of the cell cycle does DNA duplication, or replication, take place?

Interphase Correct DNA replicates during interphase. This process provides each new daughter cell with a full complement of genetic material.

During DNA replication, which nucleotide will bind to an A nucleotide in the original or parental DNA strand?

T During DNA replication, A only binds with T and T only binds with A.

During which phase of mitosis do nuclear envelopes and the nucleoli reappear?

Telophase Correct Telophase begins when the chromosomes stop moving. Nuclear envelopes form, and nucleoli reappear. Ultimately, the cell divides in two by a process known as cytokinesis.

What best describes strand characteristics as it relates to DNA replication?

The leading strand is built continuously, and the lagging strand is built in pieces.