Genetics Exam 1 Flashcards
(108 cards)
1
Q
Which organisms has characteristics that make them useful for genetic analysis
A
Model genetic organism
2
Q
What are the fundamental unit of heredity
A
Genes
3
Q
Genes come in multiple form called
A
Alleles
4
Q
Genetic information is carried in
A
DNA and RNA
5
Q
Where are genes located
A
on chromosomes
6
Q
How do chromosomes seperate
A
mitosis and meiosis
7
Q
Some traits are affected by multiple factors. True/false
A
true
8
Q
genes are known to be defined as
A
DNA sequences
9
Q
What are long molecules of double stranded DNA and protein which contain genes
A
Chromosomes
10
Q
Two of each chromosomes are called
A
Homologs
11
Q
Whatis a similarity of mitosis and meoisis in terms of chromosomes
A
chromosomes are both copied and distributed
12
Q
The two resulting daugter cells from Mitosis are called
A
Diploid
13
Q
The resulting chromosomes from Meiosis are called
A
Haploid cells
14
Q
The resulting gametes in meoisis receive how many chromosomes
A
half the number of chromosomes
15
Q
The hereditary material in chromosomes is called
A
DNA
16
Q
Which scientyist brought the idea of double helix
A
Watson and Crick
17
Q
Where are the sugar phosphate backbones located
A
on the outside
18
Q
What are the characteristics of Automosomal recessive trait
A
- Usually appears in both sex with equal frequency
- tend to skip generations
- Affected offspring are usually born to unaffected parents
- When both parents are hetero, approximately 1/4 children are affected
- appears more frequently with children of consanguineous marriages
19
Q
Mating between related person is called
A
Consanguinity
20
Q
The person from whom the pedigree is initiated is known as
A
Proband
21
Q
Characteristics of autosomal dominant
A
- Unaffected parents do not transmit the trait
- Both sexes transmit the trait to the offspring
- Does not skip generation
- Affected offspring must have affected parents unless they possess new mutation
- when one parent is affected and the other is unaffected, approximately half of the offspring will be affected
22
Q
Characteristics of X-linked recessive trait
A
- usually affects more males than females
- Affected sons are usually born to unaffected mothers, so skips generations
- Approximately half of a carrier (heterozygous) mother’s sons are affected.
- Never pass from father to son
- All daughters of affected fathers are carriers.
23
Q
Characteristics of X-linked Dominant Trait
A
- Both males and females affected, mostly females
- Does not skip generation so affected sons must have affected mothers, affected daughter has affected mother or affected father
- Affected fathers pass the trait to all their daughter
- Affected mothers (hetero) pass trait to half daughter or half sons
24
Q
Characteristics of Y-linked trait
A
- only males are affected
- Passed from father to all sons
- Does not skip generations
25
Dizygotic twins means
nonidentical twins
26
Monozygotic twins means
identical twins
27
when a trait is chared by both members of a twin pair, it is called
concordant trait
28
What is the key difference between Amniocentesis and Chorionic villus sampling
There is no culturing required in CVS
29
Describe amniocentesis
1. A sterile needle is inserted into the AMNIOTIC SAC using ultrasound
2. A small amount of amniotic fluid is withdrawn through the needle
3.Amniotic fluid contains fetal cells which are separated from the fluid
4. and cultured
5. then tests are performed on the cells
30
Describe CVS
1. CVS can be performed early in pregnancy
2. A catheter is inserted through vagina and cervix into uterus
3. it is placed in contact with chorion, outer layer of placenta
4. Suction removes a small piece of chorion
5. cells of chorion used for genetic test and no culturing required
31
Genes at the same locus or two version of the same gene with each version of same gene is defined as
allele
32
Types of dominance
Complete
Incomplete
Codominance
33
When a phenotype of heterozygote falls in between or can be distinguished from either homozygotes. This is called
Incomplete dominance
34
Heterozygotes include phenotypes of both homozygotes. this is called
Codominance
35
The percentage of individuals having a particular genotype that express the expected phenotype
Penetrance
36
The degree to which a trait is expressed is called
Expressivity
37
Which allele causes death at an early stage of development, so some genotypes may not appear
Lethal allele
38
A lethat allele affects genotypic and phenotypic ratio to
2:1 instead of 3:1
39
The AY mutation is caused by a deletion that affects which 2 genes
Agouti and Raly
40
This gene produces protein essential for mouse development
Raly
41
The deletion of Raly gene does what
connects the Raly promoter to the Agouti gene which leads to excess yellow pigment in heterozygotes and death in homozygotes
42
Huntington Disease (HD) is what type of allele
Dominant lethal allele, abnormalities not expressed until after individual has reproduced
43
Around what age does HD usually show up
late 30s or 40s
44
For a given locus, having more than two alleles are present within a group of individuals is called
Multiple alleles
45
Which blood type is known as a universal donor
O
46
Which blood type is known as a universal recipicient
AB
47
effects of genes at one locus depend on the presence of genes at the other loci is called
Gene interaction
48
The interaction of genes that are not alleles, in particular the suppression of the effect of one such gene by another
Epistasis
49
Which gene does the masking
Epistatic
50
which gene is masked
hypostatic gene
51
what is the ratio for recessive epitasis
9:3:4
52
what is the ratio for dominant epitasis
12:3:1
53
what is the alteration of multiple distinct traits by a mutation in a single gene called
Pleiotropy
54
Mitochonodria are inherited from who
the mother
55
Males are heterogametic because
the produce 2 different types of gametes
56
Females are homogametic because
they produce one type of gamete
57
The SRY gene on Y chromosomes determines
maleness
58
What is the turner syndrome
XO 1/3000 female births, underdeveloped secoindary sex characteristic
59
What is klinefelter syndrome
XXY, 1/1000 male births, small testes, facial and public hair
60
Describe poly-X females
1/1000 femal biorths, no distinctive feature tedn to be tall and thin
61
XXY males
tend to several inches taller than XY males
62
Color blindness is which trait
X-linked
63
Males have only one copy of the gene making them
hemizygous
64
Barr bodies are
inactivated X chromosomes
65
Genes found in the pseudoautosomal regions of the X and Y chromosome behave as
a
sex-linked traits.
b
autosomal traits.
c
hemizygous alleles.
Autosomes
66
The SRY gene is on the _ chromosome and it encodes a _ required for the male phenotype
a
Y, transcription factor
b
Y, Serum Response factor
c
X, transcription factor
d
X, Serum Response factor
a
Y, transcription factor
67
Dihybrid gene gives you how many punett square
16
68
How do u do trihybrid cross
fork-line diagram
69
Which law states that during gamete foremation the e segregation of alleles at one locus is independent of segregation at another locus
Independent assortment
70
Whne does independent assortment not apply
when two loci are linked on the same chromosme
71
specific place on a chromosome occupied by an allele
Locus
72
set of allele possesed by an individual organism
genotype
73
an individual organism possessing two different alleles at a locus
heterozygote
74
an individual organism possessing two of the same alleles at a locus
homozygote
75
the appearnace or manifestation of a characteristic
Phenotype or trait
76
the hypothesis that chance alone is responsible for a deviation between observed and expected values
null hypothesis
77
What is the Chi-squared test used for
for quantifying how closely an experimental observation mathes the expected outcome
78
What happens in the G1 phase
cell grows
79
What happens in the S phase
dna duplicates
80
What happens in the G2 phase
cell prepares for mitosis
81
What happens in the M phase
mitosis and cytokinesis (cell division)
82
In which phase of mitosis is the nuclear membrane present and chromosomes are relaxed
Interphase
83
In which phase of mitosis does chromosomes condense, chromosomes posses two chromatids and mitotic spindle form
Prophase
84
In which phase of mitosis do nuclear membrane disintegrates and the spindle microtubules attach to chromatids
Prometaphase
85
In which phase of mitosis do chromosomes line up on the plate
metaphase
86
which phase of mitosis Sister chromatids seperate towards opposite poles
Anaphase
87
In which phase of itosis has chromosomes arrived at spindle poles and nuclear membrane reforms
Telophase
88
The production of haploid gametes is known as
Meiosis
89
Fusion of haploid gametes is
fertilization
90
cinsequences of meiosis
genetic variation
91
In which phase does DNA synthesis and chromosome replication take place
interphase of meoisis
92
Which phase of does separation of homologous chromosomes pairs, and reduction of the chromosomes number by half take place
Meiosis I
93
which phase in meoisis is the seperation of sister chromatids
meiosis II
94
In what phase does pAIRING AND RECOMBINATION OF HOMOLGS take place
Prophase I
95
close pairing of homologous chromosomes is known as
synapsis
96
closely associated four sister chromatids of two homologs chromosomes is called
tetrad
97
Exchange of genetic infomation where the first mechanism of generating genetic variation in newly formed is called
crossing over
98
What happens in leptonema
chromosomes appear as long, single threads, homologs search
99
What happens in zygonema
a bivalent chromosome is formed, each pair of homologous chromosomes
100
Which stage doe sbivakent becoem shorter and thicker becoming tetrads
Pachynema
101
Where is chiasma formed and sister chromatids separates within tetrads
diplonema
102
where is centromeres attached to spindle fibers and nucleus and nuclear envelope break down
diakinesis
103
In meoisis I, when is crossing over complete
Metaphase I
104
Meiosis I is ca,led eductional division because
ploidy of daughter cells is halved
105
Difference in Meoisis I and meoisis II in metaphase
Meiosis I homologous pair of chromosomes align on metaphase plate
Meosis II individual chromosomes align
106
Primary spermatocyte undergoes-------- to produce 2 secondary spermatocyte
meiosis I
107
HOw does spermatocytes oroduce 4 haploid spermatids
meiosis II
108
In oogenesis do all 4 daughter cells receive equla cytoplasm
nope, only one daughter cell receives cytoplasm and the rest are polar bodies
