ANIMAL BREEDING AND GENETICS

Question 1

study of how the characteristics of organisms
are passed from parents to offspring or how
they are inherited

Answer 1

Genetics

Question 2

branch of genetics dealing with
principles of genetics exclusive to animals

Answer 2

Animal Genetics

Question 3

states that all living organisms
come from other living organisms through
the process of reproduction where each of
the parents transmits half of their genes
through the gametes to their offspring or
progenies

Answer 3

Law of Biogenesis

Question 4

involves the selective breeding of
domestic animals with the intention to
improve desirable (and heritable) qualities in
the next generation

Answer 4

Animal Breeding

Question 5

He postulated that traits are carried by
genetic material, which now known as
“gene”

Answer 5

Gregor Mendel

Question 6

He discovered that genes exist in
different form, “allele”

Answer 6

Gregor Mendel

Question 7

Alleles of different genes are inherited
differently

Answer 7

Gregor Mendel

Question 8

independently
rediscovered the transmission of genetic material

Answer 8

Carl Correns,
Hugo De Vries, and
Eric Von Tschermark

Question 9

he produced the first evidence of inheritance in animals with experiments in chicken, which proved that animals are also subject to Mendelian laws

Answer 9

William Bateson

Question 10

He coined the terms
gene, genotype and
phenotype in 1906

Answer 10

Wilhelm Johannsen

Question 11

Discovered double strand of DNA

Answer 11

James Watson and Francis Crick

Question 12

Discovered that DNA exist as double helix

Answer 12

James Watson and Francis Crick

Question 13

Found in the nucleus of the cell; is a long DNA
molecule with part or all of the genetic material of an organism

Answer 13

Chromosomes

Question 14

Occurs in pairs (2N or diploid) among autosomes
or body cells

Answer 14

Chromosomes

Question 15

A gene is the basic physical and
functional unit of heredity. Made up of
DNA (Deoxyribonucleic acid)

Answer 15

Gene

Question 16

is the hereditary material in
almost all other living organisms

Answer 16

DNA

Question 17

chromosome pairs that
are similar in length,
gene position, and
centromere location.

Answer 17

Homologous

Question 17

Heterologous

Answer 17

chromosomes that
differ in type, function,
or size

Question 17

location of a gene
in a chromosome

Answer 17

Locus

Question 18

those genes that
occupy corresponding loci
in homologous
chromosomes but that
affect the same
characteristics in a
different way

Answer 18

Allele

Question 19

gene correspond to each other

Answer 19

Homozygous gene

Question 20

gene contrast in response

Answer 20

Heterozygous gene

Question 21

actual genetic make-up or composition of an individual

Answer 21

Genotypes

Question 22

external expression or
manifestations of the genes which are
perceived by the senses

Answer 22

Phenotypes

Question 23

Characteristics that can be perceived by the naked eye

Answer 23

phenotype

Question 24

Actual genetic make-up

Answer 24

Genotype

Question 25

error in gene sequence

Answer 25

Mutation

Question 26

incorrect protein

Answer 26

Mutation

Question 27

not all are harmful

Answer 27

Mutation

Question 28

no protein

Answer 28

Mutation

Question 29

are only active when they occur in pairs of allelles

Answer 29

gene

Question 30

are only active when they occur in pairs of allelles

Answer 30

Structural genes

Question 31

control and regulate the functions of other genes

Answer 31

Regulator genes

Question 32

(additive or cumulative in their effects)

Answer 32

Intra-allellic interaction

Question 33

a dominant gene inhibits the expression of its allele

Answer 33

Complete dominance or complete recessiveness

Question 33

(non-additive)

Answer 33

Inter-allellic or non-allelic interation

Question 33

a dominant gene cannot totally masks or inhibits the expression of its allelle thus a different phenotype is produced in the heterozygous state

Answer 33

Incomplete dominance or lack of dominance

Question 33

a heterozygous individuals are preferred or selected compared to homozygous dominant or recessive because they are perceived to be superior

Answer 33

Overdominance

Question 34

involves the crossing of single pair of genes responsible for two different traits

Answer 34

Monohybrid cross

Question 34

this involved non-allellic interaction of genes with complementary or inhibitory effects

Answer 34

Epistasis

Question 35

crossing of two different phenotypes involving 2 pairs of genes

Answer 35

Dihybrid cross

Question 36

multi-trait crosses such as trihybrid crosses

Answer 36

Other crosses

Question 37

cross made when a F1 progeny or offspring is mated back to either of the parental genotypes

Answer 37

Back cross

Question 38

cross is made when a F1 progeny is mated back to the homozygous recessive parent

Answer 38

Test cross

Question 39

observable manifestation of a given character or trait of an individual

Answer 39

Phenotype

Question 40

specific combination of genes (genetic make-up) that are associated with a particular characteristic of the individual

Answer 40

Genotype

Question 41

is a function of heredity and environmental factors plus the interaction between genetics and environment

Answer 41

Phenotype

Question 42

portion of the total phenotypic variation that is due to heredity

Answer 42

Heritability estimate (h2)-

Question 43

likelihood that a certain individual will tend to repeat records for a particular trait throughout its life; expression of the same trait at different stages of the life of the same individual

Answer 43

Repeatability estimate (R)

Question 44

average superiority of the crossbreds or offspring compared to the average of their parents or of the purebred parents

Answer 44

Heterosis or hybrid vigor

Question 45

branch of genetics that deals with the qualitative characters of a given population of livestock and poultry species

Answer 45

Population Genetics

Question 46

group of individuals sharing a common gene pool

Answer 46

Population

Question 47

totality of genes that could potentially be transmitted by individuals in a population to the next generation

Answer 47

Gene pool

Question 48

totality or sum of all individuals in a breed, species, or any groupings of those individuals that inhabit a specific area or location

Answer 48

Animal population

Question 49

relative abundance or relative rarity of a particular gene in a population as compared to its own allelles in that specific population

Answer 49

Gene frequency

Question 50

states that allele and genotype frequencies in a population will remain constant from generation to generation in the absence of other evolutionary influences

Answer 50

Hardy-Weinberg Law or H-W law

Question 51

process of increasing the frequency of desirable genes, thus decreasing or eliminating the undesirable gene

Answer 51

Selection

Question 52

transfer or introduction of new genes into an existing population of genes

Answer 52

Migration

Question 53

change in the genetic code that can be due to natural or artificial means, thus new protein products are synthesized

Answer 53

Mutation

Question 54

- exist when there is small and closed population of genes and by chance can cause a change in gene population

Answer 54

Random genetic drift

Question 55

Increase homozygosis or heterozygosity of genes

Answer 55

Non- random mating

Question 56

more phenotypically similar individuals tend to mate more often

Answer 56

Assortative

Question 57

less phenotypically similar individual tend to mate more often than would be expected by chance

Answer 57

Disassortative

Question 58

is made possible through the flow of genetic material from one generation to the next

Answer 58

Reproduction

Question 59

in the formation of gametes, genes segregate so that only one of the pair is transmitted by a gamete (haploid)

Answer 59

Law of segregation or separation of gene pairs

Question 60

formation of gametes, members of one pair of genes segregate independently of other pairs

Answer 60

Law of independence or law of independent assortment

Question 61

process of gamete formation in males and females during sexual maturity or puberty.

Answer 61

GAMETOGENESIS

Question 62

formation of sperm cells at the stage of sexual maturity among males

Answer 62

Spermatogenesis

Question 63

formation of ova among sexually mature females

Answer 63

Oogenesis

Question 64

Factors affecting gametogenesis in animals

Answer 64

Extreme temperature Plane of nutrition Reproductive diseases Trauma and physical injuries

Question 65

Abnormalities affecting male reproduction

Answer 65

Sperm abnormality – double tail, broken midpiece

Question 66

Abnormalities affecting female reproduction

Answer 66

Abnormal ovaries Production of atretic follicles Hormonal imbalance (constant heat, irregular estrus)