Prelims Flashcards
1
Q
This is what an animal looks like
A
Phenotype
2
Q
The genetic make up of the organism
A
Genotype
3
Q
These two affects the phenotype of an animal
A
Genetics and Environment (GxE interactions)
4
Q
Discovery of Genetics
A
Gregor Mendel
5
Q
What did Gregor Mendel presented on his observations and experiments for the discovery of genetics
A
Pea plants
6
Q
What did Gregor Mendel found about his observations and experiments on the discovery of genetics
A
He found traits were controlled by discrete “factors” (genes)
7
Q
This theory says that all plants & animals are made of small building blocks called cells
A
Cell Theory of Inheritance
8
Q
What are cells composed of?
A
- cell wall
- nucleus
- cytoplasm
9
Q
Where did cells originate from?
A
from other cells
10
Q
It is the Unit of Inheritance
A
Gene
11
Q
Genes are particular parts of ____________ which contained in the nucleus
A
DNA
12
Q
______________ are the most basic and the smallest part of the body that are capable of sustaining the processes of life
A
Cell
13
Q
Parts of Cell that makes up most of the cell
A
Protoplasm
14
Q
Parts of Cell that contains the chromosomes that contain the genes
A
Nucleus
15
Q
Parts of Cell that also controls the cells metabolism, growth and reproduction
A
Nucleus
16
Q
Parts of Cell that surrounds the nucleus and contains mitochondria, lysosmes, Golgi apparatuses, ribosomes
A
Cytoplasm
17
Q
Parts of Cell that is semipermeable, surrounds the nucleus and cytoplasm
A
Cell membrane
18
Q
Kinds of Cell division
A
Mitosis (diploid)
- Meiosis( haploid)
19
Q
It its the way cells divide in somatic cells
A
Mitosis
20
Q
This is cell division in sex cells
A
Meiosis
21
Q
The division of cells in the animals body
which Allows animals (and us) to grow
is
A
MItosis
22
Q
Stages of Mitosis
A
- Interphase
- Prophase
- Metaphase
- Anaphase
- Telophase
23
Q
Occur in pairs in the nucleus of all body cells except the sperm and ovum
A
Chromosomes
24
Q
The number of pairs of chromosomes is called the
A
diploid number
25
What happens during mitosis?
Chromosome pairs are duplicated in each daughter cell
26
What Causes Animals to Age
- Ability of cells to continue to divide is limited
-
27
At the end of each chromosome in the nucleus there is specific repeating DNA sequence called a
telomere
28
Each time the cell divides some parts of the telomere is ___________
lost
29
As the animal ages the telomere becomes
shorter and eventually the cells stop dividing
30
This is how much a cell could divide
Telomere
31
Reproductive cells are called __________
gametes
32
The male gametes is the __________
sperm
33
female gamete is the ___________
egg
34
When the sperm and egg unite they form a
zygote
35
This specialized type of cell division is called
meiosis
36
gene that always expressed
dominance
37
gene that only expressed if not masked
recessive
38
both homologous genes expressed
Codominant or Lack of Dominance
39
Location on the chromosome of a gene
Locus
40
alternate genes that occupy corresponding sites on homologous chromosomes
allele
41
what determines the sex of animals?
Fertilization
42
Y CHROMOSOME contains the _______ gene
SRY gene
43
Its presence provides the initial signal for differentiation of the gonads in the embryo to develop into a testis rather than an ovary.
Y chromosome
44
_______ begins with separation of the double helix
Replication
45
In Replication, Synthesis is catalyzed by the enzyme ___________
DNA polymerase
46
In _________the DNA sequence in one of the strands acts as a template for synthesis of RNA
Transcription
47
In transcription, Synthesis is catalyzed by the enzyme ___________
RNA Polymerase
48
Synthesis of new proteins begins with _______________
Transcription
49
DNA is transcribed to ________ to produce _____, _______ or _______
RNA, mRNA, rRNA, or tRNA
50
Two factors responsible for genetic variation in animals
Additive and Non-Additive Gene Effects
51
What are the stop codons
UAA, UAG, UGA
52
Additive Gene Effects
Quantitative (measurable)
53
Traits that Result from Additive Gene Effects
Most of the economically important traits
-Carcass traits
-Weight gain
-Milk production
*All have moderate to high heritability
*Environment often influences expression
*Difficult to classify phenotypes into distinct categories because they usually follow continuous distribution
*Difficult to identify animals with superior genotypes
54
Control traits by determining how gene pairs act in different combinations with one another
Non-Additive Gene Effect (Observable)
55
Controlled by only one or a few pairs of genes
Non-Additive Gene
56
This is called when combinations of gene pairs give good results the offspring will be better than either of its parents
Hybrid vigor or heterosis
57
Traits That Result From Non-Additive Gene Effects
Qualitative
Phenotype is easily identified
Little environmental effect
Genotype can be easily determined
58
Important Traits involve for Livestock Improvement
- Growth
- Milk Production
59
the proportion of the total variation (genetic and environmental) that is due to additive gene effects
Heritability
60
expression of the likelihood of a trait being passed from the parent to the offspring
Heritability Estimate
61
3 Types of Systems that producers can use to select breeding animals
Tandem
Independent Culling Levels
Selection Index
62
It is the least effective of the selection methods
Tandem
63
Selection for the breeding program is based on more than one trait
Independent Culling Levels
64
Disadvantage to this type of selection is that superior performance in one trait cannot offset a trait that does not meet selection criteria
Independent Culling Levels
65
Second most effective method of selection
and most widely used
Independent Culling Levels
66
is established that gives weight to traits based on the economic importance, heritability and genetic correlations that may exists between the traits
Index of Net Merit/ Selection Index
67
Does not discriminate against a trait with only slightly substandard performance when it is offset by high performance in another trait
Selection Index
68
Provides more rapid improvement in overall genetic improvement in the breeding group
Selection Index
69
Is the most effective method of achieving improvement in genetic merit
Selection Index
70
This results in many different combinations of traits in offspring
Fertilization
71
Pass heritable characteristics from one animal to another
Genes
72
Occur in pairs just like the chromosome
Genes
73
Gene pairs that are identical are called
homozygous
74
If the gene pairs code for different expression of the same trait they are
heterozygous and the genes are called alleles
75
is the combination of genes that an individual poses
Genotype
76
Provide the code for the synthesis of enzymes and other proteins that control the chemical reactions in the body
Genes
77
These reactions determine the physical characteristics
Genes
78
Hidden Allele
Recessive gene
79
Occurs when the alleles at a gene locus are only partially expressed
Incomplete Dominance
80
Occurs when neither allele in a heterozygous condition dominates the other and both are fully expressed
Codominance
81
Sex chromosomes of female
XX
82
Sex chromosome of male
YX
83
For mammals, Sex of offspring is determined by
the male
84
For Birds, ___________ determines the sex of the offspring
Female
85
Sex chromosome of male in birds
ZZ
86
Sex chromosome of female in birds
ZW
87
Tendency for certain traits to stay together in the offspring
Linkage
88
May result in the predictions of mating not always happening
Crossover
89
This forms new chromosomes with different combinations of genes
Crossover
90
This is happen when a new trait is shown which did not exist in either parent
Mutation
91
What causes genes to mutate?
Radiation
92
is the result of using the principles of genetics
Livestock improvement
93
The amount of difference between parents and offspring is caused by
genetics and the environment
94
are used to show how much of a difference in some traits might come from genetics
Heritability estimates
95
Animals grow by
cell division
96
Ordinary cell division is called
Mitosis
97
Reproductive cells are called
gametes
98
Gametes divide by __________________
meiosis
99
________ controls an animal traits
Genes
100
Genes are sometimes changed by __________ and they are of little value in improving livestock
Mutation
101
Rules for Maximum Genetic Improvement
Have maximum genetic variation
Spend selection efforts on traits largely influenced by heredity
Observe (measure) accurately the traits carried by the animal
Use the selected animal(s) most effectively
102
Formula for selection differential
(x-z)+ (y-z)/ 2
103
How much better are the parents than the average of the population they are selected from
Selection differential
104
What influences how much genetic progress you can make?
Amount of genetic variation
Heritability
Accuracy of measurement of information
Extent of use of selected animal
105
How extensively you can make use of an animal is influenced by:
Prolificness
Generation time (with long generation interval comes slower rate of improvement)
