Quiz 3 Flashcards
1
Q
the inheritance and expression of inherited traits; some alterations may be found as part of a syndrome, or may occur independently (cleft lip and palate)
A
genetics
2
Q
a distinctive association of signs and symptoms occuring together; some are inherited and others are not
A
syndrome
3
Q
the genetic composition
A
genotype
4
Q
the observable appearance; physical, biochemical, and physiological traits of an individual
A
phenotype
5
Q
the hereditary units transmitted from one generation to another; found on chromosomes, which are located in the nucleus of a cell
A
genes
6
Q
chromosomes contain ____ which directs the production of amino acids, polypeptides, an proteins by the cell
A
dna
7
Q
does dna have the ability to duplicate itself?
A
yes
8
Q
somatic cell division
A
mitosis
9
Q
makes gametes
A
meiosis
10
Q
all cells of the body, with exception of ova and spermatozoa
A
somatic cells
11
Q
the process of cellular division in a somatic cell during a part of the cell’s life span called mitotic cycle
A
mitosis
12
Q
after each cell division is complete, the cell enters
A
gap 1 phase (g1)
13
Q
what comes after the gap 1 phase
A
s phase
14
Q
what phase does replication of dna take place
A
s phase
15
Q
the ____ phase follows the s phase, and ends when mitotic division takes place
A
gap 2
16
Q
just before the cell divides, the dna of each chromosome ____
A
replicates(makes a copy of itself)
17
Q
the chromosomes are lining up toward metaphase
A
prophase
18
Q
chromosomes at the equatorial plane of the cell; long and short arms are joined at the centromere; each identical half is called a chromatid
A
metaphase
19
Q
the chromatids are in the process of splitting
A
anaphase
20
Q
cytokinesis occurs
A
telophase
21
Q
ends up with the same number of chromosomes in the divided cells
A
mitosis
22
Q
in meiosis, the primitive germ cells reduce their chromosomes by___ and become mature germ cells
A
half
23
Q
primitive germ cells have _____ chromosomes for each pair and are called___
A
two; diploid
24
Q
mature germ cells have ____ the number of chromosomes and are called_____
A
half; haploid
25
oogonia and spermatogonia
primitive germ cells
26
ova and spermatozoa
mature germ cells
27
the primitive germ cells must ___ their chromosome number of by ______ and then become mature germ cells
reduce; half
28
before the first meiosis, the primitive germ cells will ____ their Dna. This is similar to that observed in the S phase of somatic cells.
replicate
29
then, the chromosome pairs line up to each other in a __________ (this relationship does not occur in mitosis)
point by point relationship
30
the members of each pair of chromosomes line up and exchange segments at contacts known as _____
chiasmata
31
this crossing over achieves the _______ between a chromatid of one chromosome and a chromatid of the other chromosome pair
exchange of chromosome segments
32
the chromosome separates, but no ___ of the centromere occurs
splitting
33
occasionally, both chromosomes that were crossing over do not separate, and both migrate to the same cell
nondisjunction
34
an example of this type of abnormality in which three of chromosome 21 are found
down syndrome(trisomy 21)
35
essentially a mitotic division; each chromosome splits longitudinally
second meiosis
36
is there replication of dna in second meiosis
no
37
if this occurs during the second meiosis, a chromosome does not split, and one daughter cell has a full chromosome, and the other has none
nondisjunction
38
during the early period of embryonic development, the genetic activity of one of the x chromosomes in each cell of a female embryo is inactivated
lyon hypothesis
39
for lyon hypothesis, the inactivated chromosome forms a contracted structure known as a
barr body; appears as a dark dot at the periphery of the nucleus
40
contains the basic code or template that carries all genetic information
dna
41
the bases form chains that are coiled to form the double helix; a sequence of three bases is called
codon
42
a codon codes for
an amino acid
43
the basic unit of dna
nucleotide; a/t, g/c
44
mitochondrial dna is ____ inherited; passed from mother to ____ regardless of sex
maternally ; offspring
45
the genetic code contained in dna is transcribed into
rna
46
is rna single strand?
yes
47
t/f. uracil is for dna.
false- for RNA
48
carries the message for the dna to ribosomes in the cytoplasm
messenger rna(mrna)
49
transfers amino acids from cytoplasm to mrna
transfer rna(trna)
50
what carries genetic code for the formation of that protein to the ribosome
mrna
51
___ brings amino acids to the ribosomes from the cellular cytoplasm
trna
52
the first 22 pairs of chromosomes are called the ____
autosomes
53
the 23rd pair of chromosomes is called the
sex chromosomes that determine a persons gender
54
the genes that are located at the same level(locus) in homologous chromosomes and that dictate the same functions of characteristics
alleles
55
when allelic genes are _____ the person is homozygous for that gene
identical
56
when genes are different, the person is ____ for that gene
heterozygous
57
if a gene can express its effect clinically with a single dose, as in combination, it is _____
dominant
58
if a gene requires a double dose to be expressed, the resulting characteristic or function is
recessive
59
occur at dna level
not detectable microscopically
most inherited disorders are at the level of one or both allelic genes
molecular abnormalities
60
can be observed in a karotype(a photographic representation of a persons chromosomal constitution
gross abnormalities
61
a complete second set of chromosomes
euploid
62
three or four complete sets of chromosomes
polypoid
63
any extra number of chromosomes that do not represent an exact multiple of the total
aneuploid
64
loss of part of chromosome
deletion
65
a portion of chromosome attached to another chromosome
translocation
66
a portion of a chromosome is upside down
inversion
67
a chromosome is larger than normal; the extra segment is identical to a segment of a normal chromosome
duplication
68
most frequent trisomy; down syndrome; slanted eyes; more than 30% have heart abnormalities
trisomy 21
69
what kind of tongue is seen with downs
fissured ; and gingival and periodontal disease has been reported in 90% of individuals
70
does downs have high caries
no, but high perio
71
what are some abnormalities with downs associated with teeth
hypodontia, abnormally shaped teeth, anomalies in eruption with malposition and crowding of teeth
72
a third chromosome of one type is present
trisomy
73
one chromosome of a pair is absent
monosomy
74
downs is a trisomy for chromosome ____
21
75
characterized by multiple abnormalities in various organs
trisomy 13
76
___ percent die within the first 7 mnths of life; nondisjunction of trisomy 13
70 percent
77
characteristic facial and clinical finds of trisomy 13 include
bilateral cleft lip and palate and microphthalmia or anophthalmia
78
female karyotype; usually only 1 x chromosome
turner syndrome
79
turner syndrome -- have clinically short stature with a __ of the neck and ___ of the hands and feet
webbing; edema
80
with turner syndrome, smears have a lack of
barr bodies
81
most cases of turner syndrome are the result of nondisjunction of the __ chromosome in the ___ gamete
x; paternal
82
most are from nondisjunction of the X chromosome; got too many chromosomes; xxy or xxxy; male phenotype
klinefelter
83
the greater the number of x chromosomes, the more pronounced are the __ __
clinical manifestations
84
in which syndrome is the maxilla slightly hypoplastic/underdeveloped
klinefelter syndrome
85
what abnormalities are caused by deletions
cri du chat
| wolf-hirschhorn syndrome
86
a deletion on the short arm of chromosome 5; cat-like cry at birth; mentally retarded
cri du chat syndrome
87
a deletion on the short arm of chromosome 4; cleft palate and IQ <30
wolf-hirschhorn syndrome
88
transmitted vertically from one generation to the next. males and females are equally affected; lack of penetrance may occur if an individual carries a gene without presenting any clinical manifestation
autosomal dominance inheritance
89
refers to the number of individuals affected
penetrance
90
pertains to the degree to which an individual is affected
expressivity
91
for autosomal dominant inheritance, the risk of having an affected offspring is
50%
92
individuals exhibiting an autosomal recessive trait must be homozygous for the gene
autosomal recessive
93
a mathematical estimate of the probability of an event occuring
risk
94
the chance of having deleterious genes in common increases
among close relatives
95
a family relationship
consanguinity
96
they may be either heterozygous or homo for a gene that is located on the X chromosome
women
97
if a deletrious gene occurs on the x chromosome in a male, the condition or trait will be ____ clinically regardless of the dominant or recessive behavior, since men only have one x chromosome
seen
98
if a woman is homozygotic for a dominant x linked condition, what happens
all offspring will be affected
99
because the gene is dominant, only ___ of the genes is necessary for the condition to occur
one
100
a mother who is a carrier for an x linked recessive trait has a __ risk of having an affected son and ___ risk for having a carrier daughter
5o%, 50%
101
one of the x chromosomes in the female is genetically cancelled at an early stage in embryonic development
lyon hypothesis and x linked recessive traits
102
the cancellation of the x afects x chromosomes from both maternal and paternal lines
lyon hypothesis
103
used when a condition has more than one inheritance pattern as well as differences in the degree of clinical manifestations for each of the inherited varieties
genetic heterogeneity
104
the person must be homozygous for the trait to be seen
recessive
105
is blood type O recessive
yes
106
characteristics or traits that are inherited by the participation of several genes; most physical characteristics are this; sometimes referred to as polygenic traits
oligogenic inheritance
