Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Biology > BIO202 EXAM 3 > Flashcards

BIO202 EXAM 3 Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

What is interphase?

A

When cells are not dividing

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

What is mitosis?

A

The separation of duplicated chromosomes

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

What are the 4 phases of the cell cycle?

A

G1, S, G2, and M phase

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

Which of the stages of the cell cycle make up “interphase”?

A

G1, S, and G2

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

Does Mitosis take place in prokaryotes?

A

No, they only contain 1 chromosome and are only 1 cell.

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

In G1 phase….

A

each chromosome contains 1 DNA molecule

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

In S phase…

A

DNA molecules replicate, 2 identical copies are formed, and stay attached to one another.

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

Kinetichore MT

A

attach to chromatids

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

non-kinetochore MTs

A

go from centrosome to metaphase plate and overlap

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

What’s the metaphase plate?

A

The center of the cell

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

What are the 5 phases of mitosis?

A

Prophase, Prometaphase, metaphase, anaphase, and telophase.

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

What is prophase?

A

The first stage of mitosis. This is where the chromosomes condense into visible chromosomes and then microtubule form in the cytoplasm between centriole pairs. It lengthens as the microtubules grow.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is prometaphase?

A

The second stage of mitosis. This is where the nuclear envelope fragments, the mitotic spindle invades the nucleus, and microtubules bind chromatids at kinetochores.

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

What is metaphase?

A

The third stage of mitosis. This is where centrosomes are at the opposite ends of the cell. The chromosomes that are attached to microtubules line up at the metaphase plate.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is anaphase?

A

The 4th stage of mitosis. This is where sister chromatids separate and are pulled toward opposite poles. Kinetichore MTs shorten as tubulin dimers are removed.

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

What is telophase?

A

The fifth and final phase of mitosis. This is where the nuclear envelope reforms and chromosomes partly unfold.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What stage do non-dividing cells remain in?

A

G0 phase

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

What are checkpoints?

A

Places in the cell cycle where it stops unless it is given the “go ahead” signal

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

Where are the major checkpoints?

A

The G1, G2, and M phases

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

What happens if a cell does not get the “go ahead” signal at a checkpoint?

A

It enters G0 phase

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

G1 checkpoint

A

The most important checkpoint. It is called the restriction point. If a cell gets passed the restriction point, it typically completes the cell cycle.

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

What’s beneficial about leaving the cell cycle at the restriction point?

A

It ensures that the cell has the correct amount of DNA

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

cdk’s

A

(Cyclin-dependent kinases.) Provide cell cycle signals by phosphorylating other proteins. Each cdk regulates a different step. They’re inactive alone but active when bound to a cyclin protein

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

Which cyclin acts at the G2 checkpoint?

A

MPF

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

PDGF

A

Platelet-derived growth factor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

asexual reproduction

A

offspring have the same DNA as parents (they’re identical)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

sexual reproduction

A

2 parents both contribute DNA to offspring

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What process makes sure in sexual reproduction, the offspring don’t have double the amount of DNA they should have?

A

meiosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

somatic cells

A

all cells except sperm and egg cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

chromosomes of human somatic cells

A

22 pairs of homologous chromosomes + 2 sex chromosomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

haploid number

A

n = number of chromosomes/cell in gametes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

diploid number

A

2n = the number of chromosomes in somatic cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

meiosis

A

The formation of haploid cells from diploid cells. (The formation of eggs and sperm with only 1 chromosome of each pair.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

basic steps of meiosis

A

1 round of DNA replication and 2 rounds of cell division (meiosis I and meiosis II)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What happens in interphase I of meiosis?

A

DNA is duplicated in the S phase and sister chromatids stay attached. Centrosome, centrioles duplicate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What happens in prophase I on meiosis?

A

The meiotic spindle forms. The structure of the spindle is the same in mitosis, meiosis 1 and meiosis II.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

prophase I of meiosis

A

Chromosomes attach to the spindle. Homologous chromosomes attach to each other in a process called synapsis. Then, homologous chromosomes break and rejoin at equivalent positions. This is called crossing over.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

2x2 sister chromosomes is called a

A

tetrad or bivalent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

chiasma

A

sites of crossing over

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

chromosomes that have crossed over are called

A

recombinant chromosomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Metaphase I of meiosis

A

Chromosomes line up at the metaphase plate. The homologous chromosomes stay attached. The two chromosomes of the pair are linked to opposite spindle poles.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Anaphase I of meiosis

A

Homologous chromosomes separate and sister chromatids stay attached

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

Telophase I of meiosis

A

Same events as in telophase of mitosis. Nuclei reform.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

Cytokinesis of meiosis

A

The same as mitosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

Meiosis I

A

Reductional division because each daughter cell has only one chromosome of each pair

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

Interkinesis

A

The time between meiosis I and meiosis II

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

What happens between Meiosis II

A

Centrioles and centrosomes are replicated but DNA is not.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

Meiosis II

A

Almost the same as mitosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

Prophase II

A

Spindle forms and chromosomes attach to it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

Metaphase II

A

Sister chromatids attach to opposite poles of the spindle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

Anaphase II

A

sister chromatids are separated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

Telophase II

A

Same as mitosis; nuclei form

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

DNA

A

Stores and transmits hereditary information. It codes for protein.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

Gene

A

DNA that specifies (codes for) amino acids in 1 protein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

Homologous chromosomes

A

They’re almost identical. They have the same genes that may have slight changes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

Allele

A

Different versions of the same gene

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

What causes variation between individuals?

A

Different forms of the same proteins coded for by different alleles of the same genes. They cause variation between individuals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

Homozygous (for a gene)

A

having the same allele on both chromosomes of a pair

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

Heterozygous (for a gene)

A

having different alleles on the two chromosomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

Heredity

A

Transmission of different alleles between generations by meiosis and sexual reproduction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

Genetics

A

The study of heredity and how heredity variation is passed down through generations

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

Mendel

A

discovered laws of inheritance using peas before genes and chromosomes were known

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

character

A

a heritable feature (e.g. flower color)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

trait

A

one variant of a character (e.g. purple or white flowers)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

Genetic cross

A

controlled mating of 2 organisms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q

What are “heritable factors” that Mendel postulated?

A

genes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
67
Q

genotype

A

what alleles an individual has

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
68
Q

Phenotype

A

appearance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
69
Q

Law of independent assortment

A

different characters are inherited independently

Alleles of genes on nonhomologous chromosomes assort independently during gamete formation

70
Q

An easier way of predicting outcomes of a genetic cross other than using Punnett squares

A

Calculate results for each character independently and then multiply

71
Q

Predict the possible results for a het. x. het. cross (Aa x Aa)

A

1/4 AA
1/2 Aa
1/4 aa

72
Q

Predict the possible results for a hom. x. het. cross (AA x Aa)

A

1/2 AA

1/2 Aa

73
Q

AaBbCc x AABbCC: Chance of AaBBCC

A

1/16

74
Q

How do you determine the chance of a desired phenotype?

A

Figure the chance of each genotype that fits the bill and then add the probabilities

75
Q

Co-dominance

A

two alleles both have effects

76
Q

Multiple alleles

A

more than 2 versions of a gene and its protein

77
Q

epistasis

A

1 gene affects the expression of another

78
Q

Polygenic inheritance

A

many genes contribute to phenotype

79
Q

Pleiotropy

A

1 gene has several effects on phenotype

80
Q

monohybrid cross

A

crossing two individuals each heterozygous for one character

81
Q

Law of segregation

A

The two alleles for each gene separate during gamete formation. Organisms have 2 copies of each heritable factor but each gamete has only one copy.

82
Q

locus

A

The position of a gene on a chromosome

83
Q

Linked genes

A

are on the same pair of homologous chromosomes

84
Q

wild type

A

normal appearance

85
Q

mutant

A

abnormal phenotype

86
Q

Unequal numbers in a dihybrid x double recessive test cross shows that

A

two genes are linked

87
Q

Smaller numbers of offspring are always

A

recombinants

88
Q

recombination frequency definition

A

how often recombination occurs between 2 genes

89
Q

Recombination frequency is ____ when genes are close together.

A

Low

90
Q

Recombination frequency is ___ when genes are far apart.

A

High

91
Q

recombination frequency equation

A

(# of recombinants / total number of offspring) * 100

92
Q

Genetic map

A

describes relative distances of genes along a chromosome

93
Q

1% recombination frequency =

A

1 map unit

94
Q

Autosomes

A

chromosomes in homologous pairs

95
Q

Barr body

A

compact structure on the inside of the nuclear envelope

96
Q

X-inactivation in female mammals

A

1 of the X chromosomes in each cell condenses into a Barr body early in dev

97
Q

Which X chromosomes in inactivated?

A

Decision is random and independent in each cell in the embryo

98
Q

Non-disjunction

A

failure of chromosomes to separate correctly in meiosis

99
Q

Result of non-disjunction

A

daughter cells have abnormal number of chromosomes

100
Q

Aneuploidy

A

having the wrong number of chromosomes

101
Q

Trisomy

A

1 extra chromosome

102
Q

Monosomy

A

missing 1 chromosome

103
Q

Karyotype

A

Ordered display of chromosomes from a cell in mitosis. Reveals aneuploidy

104
Q

Polyploidy

A

having extra sets of chromosomes

105
Q

Why is aneuploidy often worse than polyploidy?

A

Chromosome balance is important.

106
Q

Genomic imprinting

A

A type of inheritance pattern that doesn’t follow Mendel’s laws. During gamete formation, DNA in a few genes is modified.

107
Q

Imprints

A

remain through life but imprints are erased and new imprints are made during gametogenesis

108
Q

Genes in mitochondria and chloroplasts

A

These don’t exhibit Mendel’s laws. All mitochondria and chloroplast genes come from the mother.

109
Q

hemizygous

A

Having only one copy of sex-linked genes

110
Q

S cells

A

smooth cells that have a capsule to avoid the immune system and are pathogenic

111
Q

R cells

A

rough cells that have no capsule. Host kills them and they are not pathogenic

112
Q

Bacteriophage

A

virus that infects bacteria; turns bacteria into factories for making virus

113
Q

What is implied when it is said that DNA replication is semi-conservative?

A

Each molecule has 1 old strand and 1 new strand

114
Q

Leading strand

A

is made as a continuous strand

115
Q

Lagging strand

A

synthesized in short fragments made in the 5’ to 3’ direction then joined later.

116
Q

Okazaki fragments

A

Made 5’ to 3’. Start at the fork. DNA polymerase moves away from the fork

117
Q

Primer

A

Short segment of RNA made by primase

118
Q

DNA polymerase

A

adds dNTPs to the 3’ end of the primer

119
Q

How are primers on Okazaki fragments replaced?

A

Another DNA polymerase replaces RNA with DNA

120
Q

DNA ligase

A

joins the Okazaki fragments by forming a phosphodiester bond to link adjacent fragments into a continuous strand

121
Q

Telomeres

A

(TTAGGG) A repeated short sequence in eukaryotic chromosomes they solve the issues faced when replicating DNA. In replication it can’t get all the way to the end of the strand so it shortens it a bit. Telomeres get shortened rather than losing genetic information.

122
Q

Mismatch repair

A

DNA polymerase proofreads each dNTP after adding it and removes it if it’s incorrect

123
Q

Excision repair

A

Repair of damaged DNA. A nuclease cuts out damaged region. Then, DNA polymerase and ligase fill in the gap

124
Q

RNA polymerase II

A

The RNA pol. used to make mRNA

125
Q

The direction of transcription is called

A

downstream

126
Q

A promotor is _____ of its gene

A

upstream

127
Q

First step of transcription

A

Binding of RNA pol. to a promoter

128
Q

Transcription factors

A

Help RNA pols to bind to the promoter in eukaryotic cells

129
Q

TATA box

A

one of the many transcription factors that first bind to DNA. It is located upstream f the start of transcription

130
Q

Transcription initiation complex

A

RNA polymerase and other transcription factors

131
Q

Initiation of transcription

A

DNA strands are separated only where RNA pol is bound. RNA pol starts an RNA strand at the transcription start point

132
Q

Elongation phase of transcription

A

RNA pol. moves downstream (away from the promoter) RNA lengthens and DNA strands snap back together displacing RNA

133
Q

Termination of transcription

A

RNA pol. falls off DNA at the end of the gene. RNA is released

134
Q

Transcription terminator

A

A DNA sequence that signals the end of transcription in bacteria.

135
Q

mRNA specific event

A

In eukaryotes, mRNA transcription continues through a polyadenyation signal, but RNA pol. II is released from the DNA shortly afterward

136
Q

rRNA specific event

A

rRNA is made and assembled into ribosomes in the nucleolus

137
Q

mRNA codes for

A

protein

138
Q

mRNA processing occurs in the

A

nucleus. The initial transcription product is pre-mRNA, is converted to mRNA that leaves the nucleus

139
Q

How is pre-mRNA modified in processing?

A
  1. Addition of 5’ cap
  2. Poly-A tail
  3. RNA splicing
140
Q

Addition of 5’ cap and Poly-A tail

A

Stabilizes mRNA and facilitates ribosome attachment. Poly-A tail also enhances transport from the nucleus

141
Q

RNA splicing

A

cut and paste removal of some sequences from pre-mRNA in the nucleus (only in eukaryotes)

142
Q

Intron

A

A sequence that is removed

143
Q

Exon

A

A sequence that remains and codes for protein

144
Q

What are snRNPs?

A

(small nuclear ribonucleoproteins) made of RNA and proteins act in splicing

145
Q

How do snRNPs act?

A

They bind to the pre-mRNA at the intron ends

146
Q

spliceosomes

A

A complex formed when snRNPs bind other proteins. They bind both ends of an intron bringing them together then rejoins the ends of adjacent exons

147
Q

Alternative RNA splicing

A

Some exons may be cut out as well as introns to give a different mRNA

148
Q

tRNA

A

Folded by internal base pairing. Would look like a cloverleaf if flattened out. Interpret the genetic code

149
Q

Anticodon in tRNA

A

binds codon

150
Q

aminoacyl-tRNA synthetase

A

binds to a specific aa and a specific tRNA and covalently links them using energy from ATP hydrolysis

151
Q

Ribosomes

A

sites of protein synthesis. Both contain RNA and protein. rRNA is the most abundant RNA in a cell

152
Q

A site

A

aminoacyl-tRNA binding site

153
Q

P site

A

peptidyl tRNA binding site

154
Q

E site

A

Exit site

155
Q

tRNA binding sites

A

Ribosomes binds mRNA near 5’ end. Ribosomes have 3 tRNA binding sites

156
Q

Translation overview

A

aminoacyl-tRNAs bind to sequential codons and insert aa’s into protein

157
Q

3 stages of translation

A

Initiation, elongation, and termination

158
Q

Initiation of translation

A

Small ribosomal subunit binds mRNA at or near the 5’ end and also binds the initiator tRNA. Initiator tRNA binds to AUG in mRNA, (start codon) via its anticodon.

159
Q

AUG

A

start codon

160
Q

Initiation complex

A

Large ribosomal subunit bints to the initiator tRNA that is in the P site

161
Q

Steps in elongation (translation)

A
  1. Codon regonition
  2. Peptide bond formation
  3. Translocation
162
Q

Codon recognition

A

Incoming aminoacyl-tRNA binds to codon in A site

163
Q

Peptide bond formation

A

Peptide bonds form between new aa and carboxyl end of growing chain. The chain is now linked to tRNA in the A site

164
Q

Translocation

A

ribosomes moves along mRNA by the distance of 1 codon.

165
Q

Result of translocation

A

tRNA that was in A site is now in P site, leaving A site free to restart cycle. tRNA that was in P site is now in E site and is released from ribosome

166
Q

Termination

A

Occurs when a stop codon is present in mRNA

167
Q

release factor

A

A protein that binds to a stop codon if it’s present in the A site. It releases a finished protein from the tRNA in the P site

168
Q

Polyribosomes/polysome

A

many ribosomes on 1 mRNA

169
Q

cytosolic proteins are made on

A

free ribosomes

170
Q

Non-cytosolic proteins are made on

A

bound ribosome

Biology (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions