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PRELIMS > CYTOGEN > Flashcards

CYTOGEN Flashcards

1
Q

Observable characteristics; physical features, behaviors, risk of getting disease.

A

Traits

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2
Q

Transmission of TRAITS and biological information between generations.

A

Heredity

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3
Q

Study of HOW TRAITS are TRANSMITTED

A

Genetics

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4
Q

Concerned with how the chromosomes relate to cell behavior, specifically during mitosis and meiosis.

A

Cytogenetics

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5
Q

Genetic material; the biochemical that forms GENES; made of SUGAR and PHOSPHATE backbone; has 4 NITROGENOUS base pairs.

A

DNA

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6
Q

The 4 nitrogenous base pairs:

A

Adenine - Thymine
Guanine - Cytosine

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7
Q

sections of DNA that contain instructions on how to make proteins; passed from parent to offspring.

A

Genes

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8
Q

Complete set of genetic instructions characteristic of an organism.

A

Genome

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9
Q

An alternate form of a gene.

A

Allele

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10
Q

A combination of an organism’s alleles; “What is present?”

A

Genotype

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11
Q

OBSERVABLE version of a trait; “What is seen?”

A

Phenotype

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12
Q

Aids in predicting the likelihood of certain offspring GENOTYPES and Phenotypes.

A

Punnett Square

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13
Q

Meaning of CRISPR

A

Clustered Regularly Interspaced Short Palindromic Repeats

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14
Q

Tightly and continuously wound molecules of DNA and proteins; level of genetics; found during cell division; formed by two chromatids attached at the center by a centromere.

A

Chromosome

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15
Q

Level of genetics:

A

chromosome>DNA>gene>base pair

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16
Q

One of the two halves of a chromosome

A

Chromatid

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17
Q

Unwound DNA; only seen during INTERPHASE

A

Chromatin

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18
Q

Made of smaller structures called amino acids; built by cells using instructions found in genes.

A

Proteins

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19
Q

A sequence of three consecutive nucleotides in a DNA or RNA molecule that codes for a specific amino acid; e.g., UUU codes for phenylalanine.

A

Codon

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20
Q

Any change to a DNA’s nucleotide sequence; happens when DNA is copied.

A

Mutation

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21
Q

Having 2 sets of chromosomes in EACH CELL; chromosomes are arranged in HOMOLOGOUS PAIRS.

A

Diploid

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22
Q

Having 1 set of chromosomes

A

Haploid

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23
Q

Having the same alleles

A

Homozygous

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24
Q

Having different alleles

A

Heterozygous

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25
Q

Specific location in a gene

A

Locus/Loci

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26
Q

Pertaining to the egg and sperm cell - sex cells

A

Gametes

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27
Q

Fusion of gametes from 2 parents

A

Fertilization

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28
Q

VARIATION. ADAPTATION. SURVIVAL

  • “On the Origin of Species by Means of Natural Selection, or the Preservation of Favored races in the Struggle for Life”
  • Heredity transfers traits from parents to offspring, maintaining these variation.
A

Charles Darwin

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29
Q

Why did Gregor Mendel use peas for his experiment?

A
  1. Control fertilization
  2. Shirt life cycle
  3. Multiple characteristics
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30
Q

According to Gregor Mendel, it is the units of inheritance. It is now known as gene.

A

Elementen

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31
Q

What theory did Mendel disproved?

A

Blending Theory of Inheritance

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32
Q

3 Laws established by Mendel

A
  1. Law of Dominance
  2. Law of Segregation
  3. Law of Independent Assortment
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33
Q

He discovered the basic principles in heredity.

A

Gregor Mendel

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34
Q

According to this law, one trait (dominant) masks the other trait (recessive).

A

Law of Dominance

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35
Q

According to this law, the traits that get passed to gametes (sperm and egg) get SEPARATED.

A

Law of Segregation

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36
Q

According to this law, genes for different features segregate INDEPENDENTLY during gamete formation; a pea plant’s height does not affect its color.

A

Law of Independent Assortment

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37
Q

Discovered “NUCLEIN” (DNA)

  • Isolated DNA from the nuclei of white blood cells.
  • Found the substance in the pus of surgical bandages.
A

Friedrich Miescher

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38
Q

Who discovered that chromatin is a stainable substance inside the nucleus?

Described mitosis - observed the movement of chromosomes during cell division.

A

Walter Flemming

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39
Q

“Chromosomes are the basis of heredity.”

  • The reduction of chromosomes in meiosis is directly related to Mendel’s laws of inheritance.
A

Walter Sutton

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40
Q

He changed Mendel’s “Elementen” into gene.

A

Wilhelm Johanssen

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41
Q

“Chromosomes carry genes.”
He used fruit fly (Drosophila Melanogaster)

A

Thomas Morgan Hunt

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42
Q

1940s - Amino Acid Sequence of Insulin
1970s - DNA and Protein Sequencing

A

Frederick Sanger

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43
Q

Photo 51
X-ray Image DNA Fragments

A

Rosalind Franklin

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44
Q

Double-Helix of Structure of DNA

A

James Watson and Francis Crick

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45
Q

First animal cloned via nuclear cell transfer AKA cloning.
Cloned from the udder cell of a ewe.

A

Dolly the Sheep

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46
Q

First pet to be cloned.

A

CC the Cat

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47
Q

First person to sequence the bases in each codon.

A

Marshall Nirenberg

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48
Q

CRISPR-CAS9

A

Jennifer Doudna and Emmanuelle Charpentier

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49
Q

“genetics”

A

William Bateson

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50
Q

Pneumococcus experiments

A

Avery Mcleod, McCarthy

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51
Q

Bacteriophage labelling experiments

A

Hershey and Chase

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52
Q

Acc. to Wilson and Crick each DNA strand serves as template for the daughter or replicated DNA; conducted an experiment to determine which strand is the parent DNA and which is the daughter DNA.

A

Meselson and Stahl

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53
Q

Talked about sequencing the human genome.

A

Sinsheimer

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54
Q

2003-2006; made use of Sanger Sequencing.

A

Human genome project

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55
Q

An analysis of chromosomes during METAPHASE.

A

Karyotyping

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56
Q

Karyotyping is banded using:

A

Trypsin

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57
Q

Karyotyping is followed by stains such as:

A

Giemsa, Leishman, or both

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58
Q

Complete set of chromosomes of an individual.

A

Karyotype

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59
Q

Visual profile of stained (usually Giemsa).

A

Karyogram

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60
Q
  • Useful in making karyogram - a graphical depiction of a karyotype.
  • Giemsa binds to PO4 groups in DNA where there is high Adenine-Thymine bonding.
  • Identifies: chromosomal aberrations such as trnaslocations and rearrangements.
A

G-banding (Giemsa)

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61
Q
  • Stains heterochromatin near centromere.
  • Treat with ACID, then alkali.
  • Uses Giemsa stain.
A

C (Centromere) banding

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62
Q
  • Quinacrine stain creates FLUORESCENT bands.
  • Needs UV fluorescent microscope to view bands.
A

Q (Quinacrine) banding

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63
Q
  • Highlights satellites and stalks of acrocentric chromosomes (having off-center centromere)
  • Uses SILVER stain.
A

NOR (Nuclear Organizing Region) stain

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64
Q
  1. Blood Collection
  2. Cell culture
  3. Stopping cell division @ METAPHASE
  4. HYPOTONIC treatment of blood cells.
  5. Fixation
  6. Slide preparation
  7. Slide dehydration
  8. Enzyme treatment
  9. Staining
A

Steps in Karyotyping

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65
Q

For: detecting and locating a specific DNA sequence.

How it works: full set of chromosomes from an individual is affixed to a glass slide and then exposed to a “probe” (small piece of purified DNA tagged with a fluorescent dye)

Probe finds and then binds to its matching sequence within the set of chromosomes.

A microscope is used to view the location of the probe.

Application: for understanding chromosomal abnormalities and other genetic mutations.

A

FISH (Fluorescent In-Situ Hybridization)

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66
Q

In a nutshell: used to determine whether genes are on or off.

Determines whether DNA from an individual has a mutation or not.

Steps:
1. DNA in the sample is denatured, DNA separates into 2 strands.
2. DNA is cut into smaller pieces.
3. Smaller pieces of DNA are labeled with a fluorescent dye; RED for control/normal; GREEN for pt DNA.
4. Pt DNA and ctrl are inserted into the chip and allowed to hybridize or BIND to synthetic DNA on the chip.
5. Results:
NO mutation: red and green samples bind to the chip sequence without mutation.
WITH mutation: green sample will not properly bind to the normal sequence on the chip; instead, it will bind to the sequence with mutation.

A

DNA Microarray Analysis

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67
Q

Organized structures containing DNA associated with structural proteins called histones.

A

Chromosomes

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68
Q

Having multiple sets of chromosomes. Can occur due to: Meiotic and mitotic failures and Fusion of unreduced gametes.

A

Polyploidy

69
Q
  • Supercoiled DNA structure
  • 0.2-20 um in length
  • Found in the nucleus of eukaryotes
  • May be unduplicated which appear as lines.
  • May be duplicated; having 2 sister chromatids attached at the middle by centromere.
  • In its DIFFUSED STATES, termed as chromatin
A

Linear Chromosome

70
Q

No nucleus, genetic material floating around.

A

Prokaryotes

70
Q
  • Found usually in prokaryotes.
  • Except in Borrelia burgdorferi (CA of Lyme disease), which has a single LINEAR CHROMOSOMES.
  • Found in the nucleoid region.
A

Circular Chromosome

71
Q

Nucleated + Organelles

A

Eukaryotes

72
Q

4 Cellular Components

A

Carbs
Proteins
Lipids
Nucleic Acids

73
Q

Contains genetic material (DNA); separates DNA WITHIN the cell.

A

Nucleus

74
Q

Factory for ribosomes

A

Nucleolus

75
Q

Site of protein synthesis

A

Rough Endoplasmic Reticulum
Ribosome

76
Q

Site of lipid synthesis

A

Smooth Endoplasmic Reticulum

77
Q

Temporarily stores or transports substances

A

Vesicles

78
Q

Where sugars are made, linked into starches or joined LIPIDS AND PROTEINS where proteins finish folding; packages secretions into VESICLES that exit via plasma membrane.

A

Golgi Apparatus

79
Q

Degrades debris; deals with waste by RECYCLING cell contents.

A

Lysosome

80
Q

Cell’s way of disposing its own trash.

A

Autophagy

81
Q

Vesicle that forms from plasma membrane carries LDL to lysosomes.

A

Endosome

82
Q

Vesicle that transports molecules between cells.

A

Exosome

83
Q

Breaks down and DETOXIFIES various molecules; abundant in kidneys and liver.

A

Peroxisome

84
Q

Releases energy from nutrients.

A

Mitochondria

85
Q

Phospholipid BILAYER studded with proteins that controls which substances enter and exit the cell (signal transduction) and how the cell interacts with other cells (cellular adhesion).

A

Plasma membrane

86
Q

Cell’s skeleton
Provides framework/scaffolding

A

Cytoskeleton

87
Q

Cytoskeleton is made up of:

A

Microtubules
Microfilaments
Intermediate Filaments

88
Q

From tubulin; makescup cilia

A

Microtubules

89
Q

From actin (remember actin and myosin in muscle cells which allows muscle contraction) which allows cells to withstand stretching an compression.

A

Microfilaments

90
Q

Abundant in nerve and skin cells

A

Intermediate filaments

91
Q

In a nutshell, during the …, cells are preparing themselves for the upcoming cell division; they’re preparing themselves for something big that’s about to happen.

A

Cell cycle

92
Q

Phases under cell cycle

A

G0
Interphase (Gap 1, Synthesis phase, Gap 2)
M phase (Karyokinesis, Cytokinesis)

93
Q

It is divided into 2 gap phases (G1 and G2) and 1 synthesis phase (S phase)

A

Interphase

94
Q

Cells increase in size, makes proteins, lipids and carbohydrates as well as organelles.

A

G1

95
Q

Time out. Resting stage. No cell division occurs. When the cell decides what to do next.

A

G0

96
Q

DNA synthesis; cells go to do not disturb mode. DNA in chromosomes are REPLICATED.

A

Synthesis (S) Phase

97
Q

More proteins and organelles are synthesized and the cell prepares itself for mitosis. Synth of chemicals needed for microtubule production.

A

G2

98
Q

Cell nucleus divides

A

Karyokinesis

99
Q

Cell itself divides into daughter cells

A

Cytokinesis

100
Q

It regulates the cell cycle.

A

Proteins

101
Q

Too little mitosis

A

Injury goes unrepaired

102
Q

Too much mitosis

A

Abnormal growth or cancer

103
Q

Cell Cycle Checkpoint:

  • @G1/S transition AKA DNA damage checkpoint; cell decides whether it will divide or not.
    Checks for: Cell size, Nutrients, GFs, DNA damage

Note: Is a cell does not get a go signal to continue, it enters the G0 phase, but if conditions improve, the cells will resume with division.

A

G1 Checkpoint

104
Q

Cell Cycle Checkpoint:

  • @G2/M transition AKA APOPTOSIS checkpoint: cell makes sure that cell division goes smoothly.
    Checks for: DNA damage, DNA replication completeness

Note: Damage detected - pause at G2 for repair, Damage IRREPARABLE - cell undergoes APOPTOSIS; helps prevent cancer.

A

G2 Checkpoint

105
Q

Cell Cycle Checkpoint:

  • AKA Spindle checkpoint
    Checks for: Chromosome attachment to spindle at metaphase plate.
A

M checkpoint

106
Q

2 types of cells involved in cell division:

A
  1. Somatic (body cells)
  2. Germ/reproductive/sex cells/gametes
107
Q

Do not directly participate in sexual reproduction.

A

Somatic or Body Cells

108
Q

Mitosis occurs only in…and produces 2 daughter cells.

A

Eukaryotes

109
Q

of chromosomes in daughter cells are theme as parent cell

A

Diploid

110
Q

Sperm and egg

A

Germ/reproductive/sex cells/gametes

111
Q

Meiosis; “double division”’ 4 daughter cells with HALF (…) # of chromosomes, necessary for reproduction in Eukaryotes.

A

haploid

112
Q

Sperm (23) + egg (23) =

A

46 or 23 PAIRS of chromosomes.

113
Q

Haploid + Haploid =

A

Diploid

114
Q

When sperm cell and egg cell both having HAPLOID number of chromosomes unite, they COMBINE their chromosomes and RE-ESTABLISH the DIPLOID number of chromosomes. It is necessary for sexual reproduction among EUKARYOTES.

A

Meiosis

115
Q

90% of its time is spent on this phase.

A

Prophase 1

116
Q

Chromosomes look for their homologous pair (chromosomes with same length and centromere position)

A

Homology search

117
Q

What paris are called after homology search?

A

Bivalents or tetrads

118
Q

Intimate pairing

A

Synapsis

119
Q

Exchange of genetic material between NON-SISTER CHROMATIDS of homologous pairs; guarantees GENETIC VARIATION among offspring

A

Crossing over

120
Q

Site of genetic exchange

A

Chiasmata

121
Q

Substages of Prophase 1

A

Leptotene
Zygotene
Pachytene
Diplotene
Diakinesis

122
Q

Substages of Prophase 1:

Chromosomes condense; VISIBLE STRANDS in nucleus

A

Leptotene

123
Q

Substages of Prophase 1:

Homologous chromosomes PAIR UP during synapsis/intimate pairing

A

Zygotene

124
Q

Substages of Prophase 1:

Crossing over occurs

A

Pachytene

125
Q

Substages of Prophase 1:

SLIGHT separation of chromosomes

A

Diplotene

126
Q

Substages of Prophase 1:

Nucleolus disappears.
Nuclear envelope disintegrates.
Spindle fibers forms.

A

Diakinesis

127
Q

Mitosis

Disintegration of nuclear membrane.
Disappearance of nucleoli.
DNA begins to supercoil and appear as chromosomes.

A

Prophase

128
Q

Mitosis

Chromosomes appear as sister chromatids attached at the center by the centromere containing the kinetochore.
Centrioles appear on both poles of the cell.
Spindle fibers appear and attach to kinetochore.
Chromosomes align in the MIDDLE of the cell.

A

Metaphase

129
Q

Mitosis

Sister chromatids are pulled APART towards opposite poles.

A

Anaphase

130
Q

Mitosis

Nuclear membrane reappears.
Cleavage furrow begins to appear.
DNA begins to diffuse into the nucleus.
Nucleoli appear.

A

Telophase

131
Q

Production of 2 new daughter cells after mitosis.

A

Cytokinesis

132
Q

In (year) - accepted that there are 46 chromosomes.

A

1956

133
Q

Cytogenetics relies heavily on basic techniques:

A

Karyotyping
FISH
DNA Microarray Analysis

134
Q

When did Mendel published his findings?

A

1866

135
Q

When did Mendel got credited as the Father of Genetics?

A

1901

136
Q

Offspring that inherit a different gene variant (allele) form each parent.

A

Hybrid

137
Q

A cross of two individuals who heterozygous for a single trait.

A

Monohybrid Cross

138
Q

Law of Inheritance:

One trait (Dominant) masks another trait (recessive).

A

Law of Dominance

139
Q

Law of Inheritance:

When gametes (egg and sperm cells) are formed, each of those cells DO NOT get both copies of the allele;each of then will get 1 COPY of the allele.

A

Law of Segregation

140
Q

Law of Inheritance:

For 2 genes on different chromosomes, the inheritance of 1 gene does NOT influence the chance of inheriting the other gene.

Genes “independently assort” because they are packaged into gametes at random.

A

Law of Independent Assortment

141
Q

Year when Wilhelm Johanssen renamed Mendel’s “elementen” into gene.

A

1909

142
Q

A hormone which elongates the stem.

A

Gibberellin

143
Q

The encoded protein of this gene connects sugars into branching polysaccharide molecules.

A

R gene

144
Q

An individual with two different recessive alleles for the same gene.

A

Compound heterozygote

145
Q

Most common expression of a particular allele combination in a population. Can be recessive or dominat.

A

Wild type phenotype

146
Q

Variant of a gene’s expression that arises when the gene undergoes a change, or mutation. Permanent damage

A

Mutant phenotype

147
Q

Represents how genes in gametes join if they are on different chromosomes. A diagram used to follow parental gene contributions to offspring.

A

Punnett Square

148
Q

Crossing an individual of unknown genotype with a homozygous recessive individual; homozygous recessive is a “known” that can reveal the unknown genotype of another individual to which it is crossed.

A

Test cross

149
Q

Single gene on chromosome 15.
Gives eye color by controlling melanin synthesis.

A

OCA2

150
Q

If OCA2 is missing…

A

Albinism

151
Q

Recessive allele in OCA2

A

blue eyes

152
Q

Dominant allele in OCA2

A

brown eyes

153
Q

Gene on chromosome 15 near OCA2
Controls expression of OCA2 gene
Recessive allele of HERC2 removes control over OCA2.

A

HERC2

154
Q

2 recessive alleles in HERC2

A

blue eyes

155
Q

Dominant allele is NOT completely expressed in the presence of a recessive allele.

A

Incomplete/Partial Dominance

156
Q

Different alleles that are both expressed in a heterozygote are codominant.

A

Codominance

157
Q

Loci (specific location) are literally in the sex chromosomes e.g. recessive trait and X-linked (like color blindness)

A

Sex-linked traits

158
Q

genes are found on autosomes but resulting phenotypes are expressed only in EITHER gender.

A

Sex-limited traits

159
Q

Manifested in both genders but at different degrees of expression.

A

Sex-influenced traits

160
Q

He devised a graphical way of depicting or predicting all possible gene combinations in a cross of parents whose genes are known.

A

Reginald C. Punnett

161
Q

Scientific name for peas

A

Pisum Sativum

162
Q

Chromosomes 1-22

A

Autosomes

163
Q

23rd pari of chromosomes; determine a person’s biological sex.

A

Sex Chromosomes

164
Q

Gene masks another gene

A

Epistasis

165
Q

Allele masks another allele of the same gene

A

Dominance

166
Q

Pairing of homologous chromosomes

A

Synapsis

167
Q

Single gene influences multiple traits

A

Pleiotropy

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