Chapter 11 Flashcards
1
Q
Mendel discovered the basic principles of heredity by?
A
breeding pea plants in carefully planned experiments.
2
Q
characters
A
overall personality of something
3
Q
traits
A
specific characterisitc
4
Q
true-breeding
A
plants that produce offspring of the same variety
5
Q
hybridization
A
crossing of 2 contrasting true-breeding variants
6
Q
true-breeding parents
A
P
7
Q
F₁
A
hybrid offspring of P generation
8
Q
F₂
A
hybrid offspring of F₁ generation
9
Q
alleles account for?
A
variations in inherited characteristics
10
Q
each gene resides at?
A
a specific locus on a specific chromosome
11
Q
For each character a organism inherits?
A
2 alleles, each from 1 parent
12
Q
2 alleles at a particular locus may?
A
differ
13
Q
If 2 alleles at a locus differ then?
A
the dominant allele determines the organisms appearance
14
Q
law of segregation
A
During gamete formation, each allele separates and end up in different gametes
15
Q
homozygous
A
PP
16
Q
heterozygous
A
Pp
17
Q
Unlike homozygous, heterozygous are not?
A
true-breeding
18
Q
pheonotype
A
physical appearance
19
Q
genotype
A
genetic makeup
20
Q
testcross
A
breeding an individual with a recessive homozygotes
21
Q
A testcross can revel?
A
the genotype of a organism
22
Q
monohybrids
A
individuals that are heterozygous for a character
23
Q
monohybrid cross
A
cross between heterozygotes
24
Q
dihybrids
A
heterozygous for both characteristics
25
A dihybrid cross can determine?
whether 2 characteristics are transmitted to offspring as a package or independently.
26
law of independent assortment
genes for one trait are not inherited together with another trait.
27
law of independent assortment applies to?
genes that are not homologous or far apart on a chromosome
28
genes located near each other on a chromosome tend to be?
inherited together
29
Mendel's laws of segregation and independent assortment reflect?
rules of probability
30
rules of probablity
alleles of one gene segregate into gametes independently of another gene's alleles
31
multiplication rule
the probability that 2 or more independent events will occur together is the product of their individual properties
32
The multiplication rule can be applied to?
F1 monohybrid cross
33
addition rule
the probability that any one or more exclusive events will occur is calculated by adding together their individual probabilities.
34
The addition rule can be applied to?
F2 plants from monohybrid cross.
35
The inheritance of a single gene may deviate from?
Mendelian patterns
36
When will the inheritance characters by a single gene deviate (3)
-alleles are not completely dominant or recessive
-when a gene has more than 2 alleles
-single gene produces multiple phenotypes
37
Complete dominance
phenotypes of heterozygote and dominant homozygote are indistinguishable.
38
incomplete dominance
phenotype of F1 hybrids is somewhere between the phenotypes of the two parental variations.
39
codominance
2 dominant alleles affect the phenotype separate distinguishable ways
40
alleles
variation in a gene's nucleotide sequence
41
When does dominance and recessiveness come into play?
pathway from genotype to phenotype
42
Tay-Sachs disease
dysfunctional enzyme causes accumulation of lipids in the brain
43
Tay Sachs at organismal level
allele is recessive
44
Tay Sachs at biochemical level
phenotype is incompletely dominant
45
Tay Sachs at molecular level
alleles are codominant
46
Dominant alleles are not necessarily more?
more common in populations than recessive alleles.
47
Most genes exist in population in more than?
2 allele forms
48
Surface carbohydrates on type A blood
A carbohydrates
49
Surface carbohydrates on type B blood
B carbohydrates
50
Surface carbohydrates on type AB blood
A and B carbohydrates
51
Surface carbohydrates of type ii blood
none
52
pleiotrophy
genes have multiple phenotypic effects
53
Multiple genes could independently affect?
a single trait
54
epistasis
gene at one locus alters phenotypic expression of a gene at a second locus
55
Quantitative characters
vary in the population along a continuum
56
Quantitative variation usually indicates?
polygenic inheritance
57
polygenic inheritance
effect of 2 or more genes on a single phenotype
58
The phenotype for a character can depend on ______ as well of genotype.
environment
59
multifactorial characters
genetic and environmental factors that collectively influence phenotype
60
An organism's phenotype includes?
-physical appearance
-internal anatomy and physiology
-behavior
61
Why are humans not good subjects for genetic research?
-generation time is too long
-parents produce relatively few offspring
-breeding experiments would be unethical
62
pedigree
family tree that contains a family's history for a particular trait
63
pedigrees can be used to make predictions about?
future offspring
64
recessively inherited disorders only show up in ____ individuals.
homozygous
65
carriers
heterozygous individuals who carry recessive alleles but are phenotypically normal
66
people with recessive disorders are born to parents who are?
carriers of disorder
67
consanguineous
mating between close relatives increases the chance of mating between two carriers of the same rare allele
68
cystic fibrosis
mucus buildup in internal organs and abnormal absorption of nutrients in small intestines
69
the cystic fibrosis allele results in?
defective or absent chloride transport channels in plasma membranes.
70
sickle-cell disease
substitution of one amino acid in the hemoglobin protein in red blood cells
71
In homozygous individuals all ___ is abnormal (sickle cell disease).
hemoglobin
72
Heterozygotes that have sickle cell trait are usually healthy but?
may exhibit some symptoms
73
In regions where malaria is common you are less likely to get it if you are?
heterozygote
74
Achondroplasia
form of dwarfism caused by a rare dominant allele
75
Huntington's disease
degenerative disease of the nervous system
76
What causes Huntington's disease?
lethal dominant allele that shows no apparent phenotype until individual is 35-45
77
Lifestyle has a tremendous effect on?
phenotype for cardiovascular health and other multifactorial characters
78
Each child represents an _____ in the sense that its ____ is unaffected by the genotypreof older siblings.
independent events, genotype
