Chapter 4 Genes & Cellular Function

What are the monomeric subunits that comprise a molecule of DNA called? a. monosaccharides b. amino acids c. fatty acids d. nucleotides

nucleotides

Name the period of synthesis during which a cell makes a duplicate copy of its centrioles and all of its nuclear DNA. a. S phase b. M phase c. Telophase d. G1 phase

S phase

Describe chaperones. Multiple select question. a. They help prevent improper associations between different proteins. b. They facilitate binding of ribosomes to mRNA. c. They aid a newly synthesized protein in folding to its proper shape. d. They degrade newly synthesized polypeptides that contain inaccurate sequences. e. Some are also known as stress proteins or heat shock proteins.

a. , c. , e.

Which of the following events occur after a protein is synthesized? a. A chaperone may guide the protein in folding into the proper shape. b. Enzymes in the ER may modify the protein through posttranslational modification. c. The Golgi complex may modify the protein by adding carbohydrate chains. d. Proteins are subdivided through alternative splicing.

a. A chaperone may guide the protein in folding into the proper shape. b. Enzymes in the ER may modify the protein through posttranslational modification. c. The Golgi complex may modify the protein by adding carbohydrate chains.

Which of the following statements are true regarding introns? Select all that apply. a. An intron is a portion of mRNA that does not code for protein. b. An intron is a portion of mRNA that must be removed before translation. c. An intron is a portion of mRNA that undergoes translation in the cytoplasm.

a. An intron is a portion of mRNA that does not code for protein. b. An intron is a portion of mRNA that must be removed before translation.

Indicate the events that occur during translation. Multiple select question. a. Ribosome binds messenger RNA (mRNA). b. Transfer RNA (tRNA) anticodon binds to complementary mRNA codon. c. Transfer RNA (tRNA) delivers an amino acid to the ribosome. d. A new amino acid is linked to the growing peptide chain. e. Messenger RNA (mRNA) binds an amino acid.

a. Ribosome binds messenger RNA (mRNA). b. Transfer RNA (tRNA) anticodon binds to complementary mRNA codon. c. Transfer RNA (tRNA) delivers an amino acid to the ribosome. d. A new amino acid is linked to the growing peptide chain.

What occurs during the G1 phase of the cell cycle? a. The cell synthesizes enzymes that control cell division and also checks and repairs the newly copied DNA. b. The cell makes a duplicate copy of its centrioles and all of its nuclear DNA. c. The cell leaves the cell cycle and ceases to divide. d. The cell synthesizes proteins, grows, and accumulates the materials needed to replicate its DNA in the next phase. e. The nucleus divides.

a. The cell synthesizes proteins, grows, and accumulates the materials needed to replicate its DNA in the next phase.

Which of the following statements about codons are true? a. The genetic code is expressed as a sequence of codons. b. Every codon codes for an amino acid. c. A codon is a three-base sequence of tRNA. d. A codon is a three-base sequence of mRNA

a. The genetic code is expressed as a sequence of codons. d. A codon is a three-base sequence of mRNA.

Which of the following statements are true regarding the DNA structure? Select all that apply. a. The basic three-dimensional structure of DNA is the double helix. b. Each sidepiece is a sugar-phosphate backbone composed of phosphate groups alternating with the sugar deoxyribose. c. The nitrogenous bases face the inside and hold the two backbones together with hydrogen bonds. d. Hydrogen bonds can form either between two purines or else between two pyrimidines.

a. b. c.

Which two nitrogenous bases are classified as purines? a. thymine b. guanine c. cytosine d. adenine

adenine, guanine

Indicate which of the following are functions of mitosis. a. It produces gametes like eggs or sperm cells. b. It repairs damaged tissues. c. It allows development of an individual, composed of some 50 trillion cells, from a one-celled fertilized egg. d. It allows growth of all tissues and organs after birth. e. It replaces the cells that die with new ones.

b. , c. , d. , e.

Which of the following are characteristics of ribonucleic acid (RNA)? a. It contains a sugar called deoxyribose b. It leaves the nucleus and can be found in the cytoplasm c. It is always double-stranded d. It plays an important role in the production of proteins e. It contains nitrogenous bases A, U, C, G.

b. , d. , e.

Following transcription, only some portions of the mRNA code for the final protein. The sections of mRNA that contain necessary code are called _____, whereas the mRNA sections that do not code for the final protein are called _____.

exons, introns

Which molecule contains introns and exons? a. tRNA b. rRNA c. Pre-mRNA d. mRNA

mRNA

In which of the following subdisciplines of genetics are family relationships analyzed to predict patterns of inheritance within a family line? a. genomic medicine b. molecular genetics c. mendelian genetics d. cytogenetics

mendelian genetics

The chromosomes are seen as fully aligned on the cell equator during which phase of mitosis? a. Telophase b. Metaphase c. Prophase d. Anaphase

metaphase

During metaphase, the spindle fibers form a lemon-shaped array called the _____ spindle.

mitotic

Any change in the structure of a chromosome or a DNA molecule, often resulting in a change of structure or function in the protein produced, is known as a(n) _____.

mutation

The ______ bases in DNA are adenine, cytosine, guanine and thymine. a. sugar b. nitrogenous c. phosphate d. amino acid

nitrogenous

There are no genes that directly code for ______. Multiple select question. a. phospholipids b. glycogen c. proteins d. steroids

phospholipids, glycogen, steroids

One mRNA can have several ribosomes attached to it at one time during translation of mRNA. Which term refers to this cluster of ribosomes? a. Core particle b. Ribosomal unit c. Polyribosome d. Translation complex

polyribosome

During the mitotic phase called _____, chromosomes condense, the nuclear envelope disappears, spindle fibers grow, and centrioles migrate to the poles of cell.

prophase

Golgi vesicles containing proteins to be released from the cell will become which type of vesicle? a. Peroxisome b. Lysosome c. Endocytic d. Secretory

secretory

Which term refers to the conversion of nucleotide sequences into amino acid sequences? a. Translation b. Replication c. Transcription d. Filtration

translation

True or false: It is possible to predict the sequence of one strand of DNA if we know the sequence of the complementary strand.

true

True or false: There are no genes for glycogen, fat, steroids, phospholipids, and many other compounds, yet their synthesis is under indirect genetic control.

true

Which enzyme is responsible for transcribing DNA? a. RNA polymerase b. DNA polymerase c. helicase d. DNA ligase

RNA polymerase

True or false: Cells start dividing when they snugly contact neighboring cells or when growth factors are withdrawn.

false

When a cell replicates its nucleus and then pinches in two to form two new daughter cells it is said to be in the M phase, also called the _____ phase, of the cell cycle.

mitotic

In DNA, the base adenine pairs with the base _____.

thymine

The enzyme RNA polymerase participates in which of the following processes? a. Transcription b. Translation c. Alternative splicing d. Replication e. Protein folding

transcription

Which term refers to the process of copying the information encoded in DNA into RNA? a. replication b. translation c. initiation d. transcription

transcription

Which term refers to the step of protein synthesis in which DNA is used to make mRNA? a. modification b. transcription c. translation d. replication

transcription

The process of reading an mRNA molecule and synthesizing the protein encoded in its nucleotide sequence is known as _____.

translation

Which term refers to the step of protein synthesis in which mRNA is "read" to make protein? a. translation b. modification c. replication

translation

True or false: Proteins that must be packaged into a lysosome or secreted from the cell are synthesized in free ribosomes.

false

Alternative splicing helps explain which of the following? a. How one gene can produce more than one protein b. How different genes are activated in different cells c. How only 4 nucleotides can be used to code for 20 different amino acids d. How more than one codon can code for the same amino acid

How one gene can produce more than one protein

Indicate which of the following events occur during prophase of mitosis. Select all that apply. a. Chromosomes condense. b. Spindle fibers grow from the centrioles. c. Nuclear envelope disappears. d. Centrioles are pushed apart. e. Chromosomes migrate to opposite poles.

a. , b. , c. , d.

At one end of each tRNA there is a sequence of three nucleotides known as the _____ . This sequence is complementary to the bases on mRNA.

anticodon

Which of the following refers to a 3-base sequence found in tRNA? a. Anticodon b. Codon c. Amino acid d. mRNA

anticodon

Which molecules participate in DNA replication? a. Ribosomes b. DNA helicase c. DNA d. RNA polymerase e. DNA polymerase f. DNA ligase

b. DNA helicase c. DNA e. DNA polymerase f. DNA ligase

Which of the following statements about codons are true? a. A codon is a three-base sequence of tRNA. b. Every codon codes for an amino acid. c. A codon is a three-base sequence of mRNA. d. The genetic code is expressed as a sequence of codons.

c. & d.

The protein that guides newly synthesized proteins in folding into their proper shape and helps to prevent improper associations between different proteins is a _____.

chaperone

In the nucleus, DNA is complexed with proteins to form a fine filamentous material called ______.

chromatin

Which term refers to the filamentous material composed of DNA and associated proteins that is found in the nucleus of a cell?

chromatin

In the nucleus of a dividing cell, the chromatin condenses so that each _____, now made of two sister chromatids, can be seen with a light microscope.

chromosome

In the nucleus of a typical human cell, there are 46 DNA filaments. Which term refers to one of these structures? a. chromatin b. nucleolus c. chromosome d. nucleosome

chromosome

A three-base sequence of mRNA is called a(n) _____.

codon

The division of the cytoplasm to form two cells is called _____.

cytokenesis

Cytokinesis is the division of the cell's _____.

cytoplasm

Where is RNA usually found? a. cytoplasm b. extracellular space c. nucleolus d. nucleus

cytoplasm

If a protein is going to be used in the cytosol, it is likely to be made by ______. However, if it is going to be secreted from the cell, it is made by ______. a. free ribosomes, the Golgi apparatus b. polyribosomes on the RER, free ribosomes c. free ribosomes, polyribosomes on the RER d. the smooth ER, the rough ER

free ribosomes, polyribosomes on the RER

A(n) _____ is an information-containing segment of DNA that codes for the production of a molecule of RNA, and that in most cases codes for one or more proteins.

gene

Which of the following terms refers to a segment of DNA that codes for the production of a molecule of RNA? a. chromatin b. gene c. genome d. chromosome

gene

When a woman gives birth the hormone prolactin stimulates her mammary glands to produce casein, a protein that her body has never synthesized before. This demonstrates which of the following? a. Genes can be turned on or off. b. Genes can mutate. c. Genes are influenced by bacteria.

genes can be turned on or off

Where does the making of mRNA from DNA take place? a. in vesicles b. in nucleus c. on ribosomes d. on rough ER

in the nucleus

Where does transcription take place? a. On ribosomes b. In mitochondria c. In the nucleus d. In the Golgi apparatus

in the nucleus

The first tRNA to bind to a ribosome at the start of translation is known as what? a. initiator tRNA b. methionine c. start codon d. mRNA

initiator tRNA

During the cell cycle, G1, S, and G2 collectively make up the phase known as what? a. Prophase b. Anaphase c. Telophase d. Interphase e. Mitosis f. Metaphase

interphase

Which molecule contains introns and exons? a. mRNA b. Pre-mRNA c. tRNA d. rRNA

pre-mRNA

Which of the following are components of nucleotides? a. sugars b. proteins c. amino acids d. phosphate groups e. nitrogenous bases

sugars, nitrogenous bases, phosphate groups

Anticodons are found on which type of molecule? a. tRNA b. Exons c. DNA d. mRNA

tRNA

Which phase is a short period of time of growth and preparation for mitosis? During that time, the cell produces enzymes that control cell division, and also checks and repairs the newly copied DNA. a. M b. S c. G2 d. G1

G2

_____ occurs in three steps called initiation, elongation, and termination.

translation

How does newly synthesized mRNA pass from within the membrane-bound nucleus into the cytosol? a. It passes across the membrane, facilitated by carrier proteins. b. It is released from the nucleus through exocytosis. c. It is actively transported by a special ATPase. d. It is transported in clathrin-coated vesicles. e. It passes through nuclear pores.

It passes through nuclear pores

Indicate which of the following is NOT part of interphase. a. G2 b. S c. G1 d. M

M phase

Daughter chromosomes migrate to opposite poles of the cell during which phase of mitosis? a. Anaphase b. Prophase c. Telophase d. Interphase e. Metaphase

anaphase

Describe the events that occur during the synthesis (S) phase of the cell cycle. a. A cell makes a duplicate copy of its centrioles and all of its nuclear DNA. b. The nucleus divides. c. A cell synthesizes enzymes that control cell division as well as checks and repairs the newly copied DNA. d. A cell leaves the cell cycle and ceases to divide.

A cell makes a duplicate copy of its centrioles and all of its nuclear DNA

Which of these demonstrate accurate base pairing according to the law of complementary base pairing? a. A-C b. C-T c. G-A d. T-G e. A-T

A-T

Which statement best summarizes the role of DNA in protein synthesis? a. DNA guides the folding of a new protein after it has been assembled by RNA. b. DNA contains the genetic code that determines the amino acid sequences of proteins. c. The anticodons of DNA bind directly to amino acids, allowing them to be linked into a peptide chain. d. DNA acts as an enzyme to catalyze the conversion of mRNA into protein.

DNA contains the genetic code that determines the amino acid sequences of proteins.

Which phase is an interval between cell division and DNA replication? During this time, a cell synthesizes proteins, grows, and accumulates the materials needed to replicate its DNA in the next phase. a. G1 b. G0 c. S phase d. M phase e. G2

G1

Which phase is a short period of time of growth and preparation for mitosis? During that time, the cell produces enzymes that control cell division, and also checks and repairs the newly copied DNA. a. G1 b. S c. G2 d. M

G2

What is the role of mRNA in protein synthesis? a. It stays within the nucleus and serves as the template for transcription. b. It binds free amino acids and delivers them to the ribosome to be added to a growing protein chain. c. It opens the DNA helix and reads the bases from one strand of DNA. d. It carries the genetic code from the nucleus to the cytoplasm.

It carries the genetic code from the nucleus to the cytoplasm.

What occurs during the G2 phase of the cell cycle? a. The cell makes a duplicate copy of its centrioles and all of its nuclear DNA. b. The cell leaves the cell cycle and ceases to divide. c. The cell synthesizes enzymes that control cell division and also checks and repairs the newly copied DNA. d. The nucleus divides.

The cell synthesizes enzymes that control cell division and also checks and repairs the newly copied DNA.

Which of the following is a true statement? a. All genes in all cells are activated during protein synthesis. b. Which proteins a cell makes is determined by which genes are activated in that cell. c. Only activated proteins combine to form mRNA molecules during protein synthesis. d. Different cells make different proteins because they contain different genes.

Which proteins a cell makes is determined by which genes are activated in that cell.

Translation occurs in three steps. Place these steps in chronological order. a. initiation b. termination c. elongation

a. , c. , b.

When do cells divide? a. When they snugly contact neighboring cells or when nutrients or growth factors are withdrawn b. When they grow large enough to have enough cytoplasm to distribute to their two daughter cells c. When neighboring cells die, opening up space in a tissue to be occupied by new cells d. When they have replicated their DNA, so they can give each daughter cell a duplicate set of genes

b. , c. , d.

Since there are no genes coding for carbohydrates, nucleic acids, or lipids, how do cells produce them? a. Cells are produced with all the products they need. b. Cells obtain all of these products by endocytosis. c. Genes encode enzymes that synthesize these products. d. Cells can produce carbohydrates, nucleic acids, and lipids out of proteins.

genes encode enzymes that synthesize these products

When synthesized proteins are to be exported out of the cells, they are packaged into secretory vesicles that originate in what organelle? a. Nucleus b. Ribosomes c. Golgi complex d. Smooth endoplasmic reticulum

golgi complex

Which molecule carries the genetic code from the nucleus to the cytoplasm? a. tRNA b. mRNA c. DNA d. rRNA

mRNA

Exposure to chemicals and radiation may lead to changes in DNA structure called _____.

mutations

The process by which a cell makes a copy of its DNA so it can give complete and identical copies of all of its genes to each daughter cell is DNA _____.

replication

The process by which a cell makes a copy of its DNA, creating two new strands is referred to as which of the following? Multiple choice question. a. Initiation b. Transcription c. Translation d. Replication

replication

The law of complementary base pairing states that a cell can do which of the following? a. Reproduce one strand of DNA based on information in the other b. Regenerate ATP from ADP c. Increase the number of amino acids in a protein d. Align pairs of chromosomes at the equator of the cell during metaphase

reproduce one strand of DNA based on information in the other

______ are the cell structures that process coded genetic messages and assemble amino acids into proteins. a. Smooth ER b. Ribosomes c. Lysosomes d. Mitochondria

ribosomes