Genetics Flashcards
(77 cards)
1
Q
Genetics
A
transfer of genes from one generation to the next
2
Q
Animal breeding
A
applied science-mating to produce a desirable offspring
3
Q
Genomics
A
basic science- mechanism
4
Q
Chromosome
A
structural unit of DNA
5
Q
Haploid
A
1N- 1/2 DNA
6
Q
Diploid
A
2N- full DNA
7
Q
Number of chromosomes in humans
A
46
8
Q
Number of chromosomes in Cattle
A
60
9
Q
Number of chromosomes in Horses
A
64
10
Q
Number of chromosomes in Swine
A
38
11
Q
Number of chromosomes in Sheep
A
54
12
Q
Number of chromosomes in Goat
A
60
13
Q
Number of chromosomes in Chicken
A
78
14
Q
DNA
A
Deoxyribonucleic acid
15
Q
Gene
A
single unit of DNA
16
Q
Genotype
A
genetic composition
17
Q
Phenotype
A
expressed composition
18
Q
A
A
Adenine
19
Q
T
A
Thymine
20
Q
C
A
Cytosine
21
Q
G
A
Guanine
22
Q
_____ replaces thymidine in RNA (T=U)
A
Uracil
23
Q
A codon is
A
3 nucleotides
24
Q
The start of a colon is
A
AUG
25
Single nucleotide polymorphisms (SNPs)
```
Errors during DNA replication can result in omitted, substituted, or extra base pairs
◦ Stop codon
◦ Phase shift
◦ Altered function
◦ No difference
“A lot of mutations you will never see"
```
26
Homozygous
Identical
27
Heterozygous
Disimilar
28
Dominant traits
one allele is always expressed
29
Replication
DNA makes copy of itself
30
Recessive
only show their effect if the individual has two copies otherwise is masked
31
Difference between DNA and mRNA
DNA is double stranded DNA uses Thymine
| mRNA is single stranded mRNA uses Uracil
32
Transcription
segment of DNA is copied into RNA
33
Translation
mRNA is translated into a protein
34
Central Dogma of Life
DNA - RNA - Protein
| Transcription Translation
35
Dominant traits in cattle
Polled
White face
Solid Color
36
Recessive traits in cattle
Horned
solid color in face
irregular color
37
Dominant traits in horse
Black base color
| chestnut mane
38
Recessive traits in horse
chestnut base color
| flaxen mane
39
Dominant traits in chicken
Feathered shanks
| Dominant white
40
Recessive traits in chicken
Clean shanks
| recessive white
41
Dominant traits in sheep
Brown Eyes
| white wool
42
Recessive traits in sheep
blue eyes
| black wool
43
Codominance
both traits are expressed
44
Quantitative Traits
```
Can measure phenotype but cannot determine specific genotype
affected by many genes
environmental influence
continuous variation
economic importance
```
45
Qualitative traits
affected by one or few genes
| little environmental influence
46
Quantitative Traits Examples
weight
milk production
fertility
any performance metric - rate of gain, speed
47
Selection is based on _______. Changes population slowly over time
phenotype
48
Why is selection important
Important tool for genetic improvement
49
Selection is
selecting for favorable mating and prohibiting unfavorable
50
Heritability
% of the __________ that is genetic and ___________ from parents to ________
Ranges from _______
It’s an _________
phenotypic, transmitted, progeny
0 - 100%
estimate
51
What is a breed
Animals of common origin
- have common characteristics
- are bred to pass traits
- bred associations
- politics (there has to be enough interest to buy a bred)
52
Types of operation
Seed stock-
Commercial-
genetic selection (targeting the future of the industry)
expand and utilize those genetics
53
Expected Progeny Difference (EPD)
amount by which the average progeny is expected to exceed the average of the herd or population
54
```
EPDs
Our best tool for ____________
Used to compare ____________
Available for _____, _____, and _____
Theoretical average = __
```
genetic selection
genetic potential
cattle, sheep, swine
zero (0)
55
_______ Holstein cows imported from the Netherlands, ending in 1905 due to __________
10,000
| Hoof‐ and‐Mouth
56
DNA has _____ helix structure
double
57
DNA is made up of __________
nucleotides
58
Nucleotides are made up of ______, __________, and _____________.
Sugar, phosphate and nitrogenous base
59
```
Nitrogenous base are
_________ (A)
_________ (T)
_________ (C)
_________ (G)
```
◦ Adenine
◦ Thymine
◦ Cytosine
◦ Guanine
60
Important considerations when using EPDs
Resources
Must consider pairing
Avoid relying on single traits
What direction should we go to get the offspring we want to produce
61
______ Holstein cows imported from the Netherlands, ending in 1905 due to __________
10,000, Hoof‐ and‐Mouth
62
Osborndale Ivanhoe was responsible for BLAD (Bovine Leucocyte Adhesion deficiency) resulted in
death in all homozygous animals
63
Toy Story has produced over __________ units of semen
two million
64
Straight breeding
mating animals of the same breed
65
Crossbreeding
mating animals of different breed
66
Composites
meant to combined specific traits
67
Hybrids ‐‐ used in the swine and poultry industry
genetic lines specifically selected
68
Why Crossbreed
Breed complementation- match strength and weaknesses
69
Heterosis
progeny shows qualities superior than parents
70
Relationship b/w Heterosis and Heritability
as one increases the other decreases
71
Inbreeding
breeding closely related individuals
72
What are we trying to do with inbreeding
trying to reduce variation of specific genes
73
Line breeding
outstanding individual
74
Rotational Crossbreeding (2-3 breeds)
trying to maximize heterosis
75
Terminal
all progeny go to market
| buy in breeding stock
76
What is the goal of Terminal crossbreeding program
growth and carcass traits
77
Why use breeds when you can use crossbreds?
Breeds have specific traits which allows us to predict what the offspring is going to look like if we cross them. Whereas if I cross two crossbreds, there is higher variation on how those traits may show on the offspring.
