Chapter 3 Mastering

What events occurs during transcription?

A molecule of RNA is formed based on the sequence of nucleotides in DNA.

If the DNA triplet is ATC, the tRNA anticodon will be __________.

AUC

primary active transport

Active transport that relies directly on the hydrolysis of ATP.

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

Anaphase

Which of the following statements about cells is FALSE? Although human cells are diverse in size, shape, and function, they have essentially the same organelles and general structure. Cells join together to form organelles, which then form our organs and organ systems. Cells are the most basic units of life. The cells in our bodies collectively carry out all of the functions necessary for us to stay alive.

Cells join together to form organelles, which then form our organs and organ systems.

Metaphase

Chromosomes align in the center of the cell

Telophase

Completion of cytokinesis Chromosomes relax and nuclear envelopes form Chromosomes reach the opposite ends of the cell

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

Cytokinesis

What does not play a role in translation?

DNA

What is not a major difference between DNA and RNA?

DNA is found in the nucleus and cytoplasm, but RNA is only found in the nucleus

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

DNA ligase

What DNA replication is FALSE?

DNA ligase adds nucleotides to the lagging strand.

The enzyme that builds synthesizes the new DNA strand during replication is __________.

DNA polymerase

What builds new strands of DNA?

DNA polymerase

osmosis

Diffusion of water through a selectively permeable membrane

The cell cycle is divided into two main parts: interphase and cell division. Interphase is the period in which the cell is performing normal functions and not actively engaged in cell division. Most of your body's cells spend a lot of their time in interphase. Before a cell can divide, what must occur during interphase?

Each chromatin fiber is duplicated in the nucleus.

What are the phases of interphase?

G1, S, and G2

From the rough endoplasmic reticulum, proteins are often sent to the ______________ for further posttranslational modification:

Golgi apparatus

What is the basic difference between simple diffusion and facilitated diffusion across a cell membrane?

In facilitated diffusion, molecules only move with the aid of a protein in the membrane.

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

Interphase

List the first to the last steps to describe the correct order of events in interphase, mitosis, and cytokinesis.

Interphase, Prophase, Metaphase, Anaphase, Telophase and Cytokinesis, Daughter cells

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

Metaphase

The initiator tRNA always brings the amino acid:

Methionine

Prophase

Mitotic spindle fibers form and attach to centromeres Nuclear envelope breaks up DNA condenses into chromosomes Centrosomes move to opposite sides of the cell

Facilitated diffusion

Movement of specific molecules across cell membranes through protein channels

What is most likely to move through the cell membrane by facilitated diffusion?

Na+

What effect do you think deficiencies in lysosomal enzymes would have on phagocytes?

Phagocytes would lose the capability to digest bacteria.

what is the amino acid sequence, based on the following mRNA: UUUAAACCCGGG.

Phe - Lys - Pro - Gly

Which of the following membrane transport mechanisms requires ATP?

Primary active transport

Active Process (4 answers)

Primary active transport, secondary active transport, endocytosis, exocytosis

Exocytosis

Process by which a cell releases large amounts of material

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

Prophase

Human cell division is commonly referred to as the Mitotic (M) phase, since most body cells only undergo mitosis. The M phase of the cell cycle includes mitosis and cytokinesis. Mitosis is the division of the cell's nucleus into two genetically identical daughter nuclei and consists of four separate phases.

Prophase, Metaphase, Anaphase, Telophase

The enzyme that synthesizes the RNA strand during transcription is:

RNA polymerase

Which of the following organelles synthesizes proteins?

Ribosome

Passive Process

Simple diffusion, facilitated diffusion, and osmosis

Anaphase

Sister chromatids separate into chromosomes Chromosomes move along the spindle fibers

During which of the following phases does DNA replication occur?

Synthesis

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

T

Cytokinesis occurs concurrently with what stage of mitosis?

Telophase

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

Telophase

If a person is severely dehydrated, their extracellular fluids will become hypertonic to the intracellular fluid. What do you predict will happen to the person's cells?

The cells will lose water and shrink.

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.

Which of the following occurs as a result of ribosomal translocation?

The tRNA that was in the A site moves into the P site.

Predict what will happen to a patient's red blood cells if you give the patient an IV of pure water.

They will burst.

The RNA base complementary to A in DNA is:

U

Which of the following is NOT one of the functions of plasma membrane proteins? act as receptors act as transport vesicles act as channels act as enzymes

act as transport vesicles

What is not required for osmosis to occur?

cellular energy

The button-like structure that holds homologous chromosomes together at their middles during cell division is called the ... ... transport vesicles bring something into a cell. The stage of the cellular lifecycle between divisions is called ... The cellular material between the cell membrane and the nucleus is called ... ... transport vesicles send something outside of a cell. cytoplasm? centromere? Exocytic? interphase? endocytic?

centromere Endocytic interphase cytoplasm Exocytic

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

chromatids

A sequence of three nucleotides on mRNA is called:

codon

Which of the following is a function of lysosomes?

digest and recycle damaged organelles

Nerve cells do not have centrioles. Therefore, they are NOT able to __________.

divide

The prefix .. means "outside." The prefix .. means "cell." The prefix .. means "within," "inside" or "between." The prefix .. means "center." The prefix .. means "within." inter? exo? cyto? endo? centr?

exo- cyto- inter- centr- endo-

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

exocytosis

The coding sequences, which are kept during RNA processing, are called __________.

exons

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

Which of the following is not a major function of proteins in the cell membrane?

forming the entire glycocalyx

Solution A and solution B are separated by a semipermeable membrane. Solution A contains 1% glucose, solution B contains 5% glucose. By diffusion:

glucose will move from solution B to solution A.

Which of the following is an example of posttranslational modification:

glycosylation

Diagram of a red blood cell inside a solution. The red blood cell appears shrunk. There are 7 solute molecules inside the cell and over 100 solute molecules outside the cell. This cell is in a(n) __________ solution.

hypertonic

If the ECF is more concentrated than the cytosol, then the ECF is:

hypertonic

What solutions contains the most solute?

hypertonic

Where in a typical eukaryotic cell would you expect to find genes?

in the DNA within the cell's nucleus

The toxin ricin rapidly and completely deactivates the ribosome. It is lethal to humans, because it will:

inhibit translation

In general, to maintain homeostasis the relationship between our intracellular and extracellular fluids should be which of the following?

isotonic to each other

What acts as the digestive system of the cell, breaking down materials?

lysosome

What does not occur during RNA processing?

mRNA attaches to the small subunit of a ribosome.

What is a statement about mRNA?

mRNA moves from the nucleus to the cytoplasm following RNA processing.

Regions of the body which require large surface area for absorption, such as the cells covering the inner surface of the small intestine, often have __________.

microvilli

What does the golgi apparatus function lists or functions of this organelle?

modify, sort, and package proteins and lipids

A primary active transport process is one in which __________.

molecules move through transport proteins that have been activated by ATP

Simple diffusion

movement of a solute from an area of high concentration to an area of low concentration

What best explains diffusion?

movement of molecules from an area of high concentration to an area of low concentration

Most of a cell's DNA is located in its:

nucleus

What part of a cell membrane is usually in contact with the interstitial fluid?

phosphate heads of phospholipids

Which of the following is the main component of the cell membrane?

phospholipids

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

primary active transport

Endocytosis

process by which a cell takes material into the cell by infolding of the cell membrane

Transcription factors bind to the ___________ on DNA.

promoter sequence

During which of the following phases does chromatin condense and become chromosomes?

prophase

What are the phases of mitosis?

prophase, metaphase, anaphase, telophase

What is NOT one of the three major components of a typical eukaryotic cell?

ribosome

The site of translation is

ribosomes in the cell cytoplasm.

Which of the following is a characteristic of the cell membrane?

semipermeable

The paired and identical copies of a chromosome, which are joined at a centromere, are called __________.

sister chromatids

What is least likely to increase the rate of diffusion?

small concentration gradient

Diffusion is the movement of _________.

solute down its concentration gradient

Cholesterol in the plasma membrane __________.

stabilizes the structure of the plasma membrane when the temperature changes

If the ECF is hypotonic, the cell will:

swell.

Predict the meaning of the term "reverse transcription."

synthesis of DNA using RNA as a template

Molecule with three nitrogenous bases (AAG) on one side and the amino acid Phenylalanine attached to the opposite side. This is a molecule of __________.

tRNA

Splicing causes:

the exons to join back together

Solution A and solution B are separated by a semipermeable membrane. Solution A contains 1% glucose, solution B contains 5% glucose. By osmosis:

water will move from solution A to solution B.