Smartbooks Chapter 4 Flashcards

1
Q
Which of the following are components of nucleotides?
Phosphate groups
Nitrogenous bases
Sugars (ribose or deoxyribose)
Amino acids
Proteins
A

Phosphate groups
Nitrogenous bases
Sugars (ribose or deoxyribose)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

In DNA, the base adenine pairs with the base ____

A

thymine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

How many hydrogen bonds do adenine and thymine form with each other?

A

Two

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

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

A

chromatin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

In the nucleus of a typical human cell, there are 46 DNA filaments. Which term refers to one of these structures?

A

Chromosome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Which of the following best describes a histone?

1) A protein component of chromatin that helps to organize and package DNA
2) The pinched spot on the chromosome where two sister chromatids join together
3) A long, noncoding sequence of DNA
4) A segment of the DNA that carries the genetic code for a particular protein

A

1) A protein component of chromatin that helps to organize and package DNA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

When a cell is preparing to divide, it makes an exact copy of all its nuclear DNA. Each chromosome then consists of two parallel filaments called _____ chromatids

A

sister

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How many hydrogen bonds do guanine and cytosine form with each other?

A

3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Which of the following is true about the centromere?

a) It is what chromosomes attach to, so they can be pulled to the middle of the cell.
b) It is located at the tips of the chromosome “arms”.
c) It is where sister chromatids are joined together.
d) It is a short stretch of DNA wrapped around a cluster of histone proteins.

A

c) It is where sister chromatids are joined together.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

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

a) Centrioles
b) Chromatids
c) Chromatin
d) Chromosome

A

c) Chromatin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

mRNA is short for ____ RNA

A

messenger

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

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

A

chromosome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q
Histones are \_\_\_\_\_\_.
triglycerides
proteins
carbohydrates
nucleic acids
A

proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How are DNA and RNA different?
A) RNA consists of only one nucleotide chain whereas DNA is a double helix.
B) RNA contains a sugar called ribose whereas DNA contains a sugar called deoxyribose.
C) RNA contains adenine, cytosine, thymine and guanine whereas DNA contains adenine, cytosine, thymine and uracil.
D) RNA is much smaller. DNA, by contrast, averages more than 100 million base pairs long.

A

A) RNA consists of only one nucleotide chain whereas DNA is a double helix.
B) RNA contains a sugar called ribose whereas DNA contains a sugar called deoxyribose.
D) RNA is much smaller. DNA, by contrast, averages more than 100 million base pairs long.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q
When a cell is preparing to divide, it makes an exact copy of all its nuclear DNA. Each chromosome then consists of two parallel filaments called what?
Chromatin
Sister chromatids
Base pairs
Histone groups
A

Sister chromatids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

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.

A

gene

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q
A centromere holds \_\_\_\_\_\_\_ together.
proteins
kinetochores
sister chromatids
RNA
A

sister chromatids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Which of the following are true statements about the genetic code?

a) The genetic code relates mRNA codons to protein structure.
b) Each codon in the genetic code can stand for two or more amino acids.
c) The genetic code is expressed as three-nucleotide long sequences called codons.
d) The genetic code allows 20 amino acid to be coded by only 4 different nucleotides.

A

a) The genetic code relates mRNA codons to protein structure.
c) The genetic code is expressed as three-nucleotide long sequences called codons.
d) The genetic code allows 20 amino acid to be coded by only 4 different nucleotides.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

rRNA is short for _____ RNA.

A

ribosomal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

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

A

codon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

A polypeptide is made of 31 amino acids. What is the minimum number of DNA nucleotides needed to code for this number of amino acids?

A

93 base pairs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Transcription is the process of copying genetic instructions from a molecule of _____ to mRNA.

A

DNA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

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

A

The genetic code is expressed as a sequence of codons.

A codon is a three-base sequence of mRNA.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Which term refers to a sequence of three DNA nucleotides that codes for one amino acid?

a) codon
b) base triplet

A

b) base triplet

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q
The enzyme RNA polymerase participates in which of the following processes?
Transcription
Replication
Protein folding
Alternative splicing
Translation
A

Transcription

26
Q
Where does transcription take place?
In the Golgi apparatus
On ribosomes
In the nucleus
In mitochondria
A

In the nucleus

27
Q

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

A

translation

28
Q

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

A

codon

29
Q

What is the role of mRNA in protein synthesis?

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

A

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

30
Q
Which enzyme is responsible for transcribing DNA?
DNA polymerase
DNA ligase
RNA polymerase
Helicase
A

RNA polymerase

31
Q

Transcription is the process of copying genetic instructions from a molecule of
_____ to mRNA.

A

DNA

32
Q

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.

A

anticodon

33
Q
Which term refers to the conversion of nucleotide sequences into amino acid sequences?
Replication
Filtration
Translation
Transcription
A

Translation

34
Q
Which molecule carries the genetic code from the nucleus to the cytoplasm?
tRNA
DNA
rRNA
mRNA
A

mRNA

35
Q

A base _____ is a consecutive sequence of three DNA nucleotides that codes for one amino acid.

A

triplet

36
Q

Translation occurs in three steps. List these steps in chronological order.

A

Initiation
Elongation
Termination

37
Q

The cluster of several ribosomes reading one mRNA during translation is called a _____

A

polyribosome

38
Q
Which of the following refers to a 3-base sequence found in tRNA?
mRNA
Anticodon
Codon
Amino Acid
A

Anticodon

39
Q
Golgi vesicles containing proteins to be released from the cell will become which type of vesicle?
Lysosome
Secretory
Endocytic
Peroxisome
A

Secretory

40
Q

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 its DNA is called _______

A

replication

41
Q

One mRNA can have several ribosomes attached to it at one time during translation of mRNA. What term refers to this cluster of ribosomes?

A

Polyribosome

42
Q
When synthesized proteins are to be exported out of the cells, they are packaged into secretory vesicles that originate in what organelle?
Smooth endoplasmic reticulum
Golgi complex
Ribosomes
Nucleus
A

Golgi complex

43
Q

Where does translation take place?

A

On the ribosome

44
Q
Which enzyme is responsible for unwinding DNA during DNA replication?
Ligase
Transferase
Helicase
Polymerase
A

Helicase

45
Q
Which enzyme joins the newly synthesized DNA segments during DNA replication?
Transcriptase
Polymerase
Ligase
Helicase
A

Ligase

46
Q

List the phases of the cell cycle in the correct order starting with G1.

A

G1
S
G2
M

47
Q

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) Increase the number of amino acids in a protein
c) Align pairs of chromosomes at the equator of the cell during metaphase
d) Regenerate ATP from ADP

A

a) Reproduce one strand of DNA based on information in the other

48
Q
Name the period of synthesis during which a cell makes a duplicate copy of its centrioles and all of its nuclear DNA.
M phase
Telophase
S phase
G1 phase
A

S phase

49
Q

Name the correct order of the phases of mitosis from beginning to end.

A

Prophase, metaphase, anaphase, telophase

50
Q

During DNA replication, the new short segments of DNA in one of the strands are joined together by the enzyme DNA _____

A

ligase

51
Q

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

A

prophase

52
Q

During the cell cycle, the stages G1, S, and G2 make up what phase?

A

Interphase

53
Q

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

A

mitotic

54
Q

Which of the following occurs during anaphase?
A) Chromosomes align along the center or equator of the cell.
B) Centrioles migrate to the poles of cell.
C) Chromosomes are gathered at the poles of the cell.
D) Daughter chromosomes migrate to opposite ends of the cell.

A

D) Daughter chromosomes migrate to opposite ends of the cell.

55
Q

Indicate which of the following events occur during prophase of mitosis. Select all that apply.
A) Chromosomes condense.
B) Centrioles are pushed apart.
C) Chromosomes migrate to opposite poles.
D) Nuclear envelope disappears.
E) Spindle fibers grow from the centrioles

A

A) Chromosomes condense.
B) Centrioles are pushed apart.
D)Nuclear envelope disappears.
E) Spindle fibers grow from the centrioles.

56
Q

The new nuclear envelopes forms, new nucleoli appear, and the mitotic spindle vanishes during which phase of mitosis?

A

Telophase

57
Q

The division of the cytoplasm to form two cells is called ______

A

cytokinesis

58
Q

The chromosomes are seen as fully aligned on the cell equator during which phase of mitosis?

A

Metaphase

59
Q

Daughter chromosomes migrate to opposite poles of the cell during which phase of mitosis?

A

Anaphase

60
Q

Select that statements that describe telophase.
A) Chromosomes align along the center of the cell.
B) Chromatids cluster on each side of the cell.
C) A nuclear envelope reappears.
D) DNA is replicated.
E) Centrioles migrate to the poles of cell.

A

B) Chromatids cluster on each side of the cell.

C) A nuclear envelope reappears.