Animal Science (Genetics) Flashcards
It is the branch of biology that deals with heredity and variation of organisms.
Genetics
The transmission of traits from generation to the next generation.
Heredity
This deals with the genetic differences between organisms.
Variation
The smallest unit of inheritance.
Gene
They act as segments of DNA on a chromosome.
Gene
This stores and transmits genetic information from cell to cell and from parent to offspring.
Gene
It is capable of replicating itself with great consistency and precision.
Gene
The mutation of genes can subsequently be copied and replicated. [T/F]
True
It is found in the nucleus of the cell. It also forms the backbone of the chromosome.
DNA
The structure of the DNA.
Spiral / Double helix
Which of the following is NOT an N base of the DNA?
• Guanine
• Adenosine
• Thymine
• Cytosine
Adenosine.
The 4 N bases of the DNA are Guanine, Adenine, Thymine, and Cytosine.
These are the proteins that are wrapped arounnd with thin fibers of DNA.
Histones
The bead-like structure that is formed by the histone and DNA structure.
Nucleosome
These are slender, thread-like strands that contain genes or units of inheritance.
Chromosomes
Humans:
2n chromosomes:
Number of pairs:
Humans
2n chromosomes: 46
Number of pairs: 23
Cattle
2n chromosomes:
Number of pairs:
Cattle
2n chromosomes: 60
Number of pairs: 30
Sheep
2n chromosomes:
Number of pairs:
Sheep
2n chromosomes: 54
Number of pairs: 27
Swine
2n chromosomes:
Number of pairs:
Swine
2n chromosomes: 38
Number of pairs: 19
Goats
2n chromosomes:
Number of pairs:
Goats
2n chromosomes: 60
Number of pairs: 30
Horse
2n chromosomes:
Number of pairs:
Horse
2n chromosomes: 64
Number of pairs: 32
Mule
2n chromosomes:
Number of pairs:
Mule
2n chromosomes: 63
Number of pairs: 31+1n
Turkey
2n chromosomes:
Number of pairs:
Turkey
2n chromosomes: 82
Number of pairs: 41
Chicken
2n chromosomes:
Number of pairs:
Chicken
2n chromosomes: 78
Number of pairs: 39
Each body cell contains one or two pairs of sex chromosomes. [T/F]
False.
Each body cell contains only one pair of sex chromosomes.
Chromosomes that are not sex chromosomes are called ______.
Autosomes.
In mammals, females have XX and males have XY.
In poultry, females have __ and males have __.
In poultry, females have ZW and males have ZZ.
This is the specific location of a gene in a chromosome.
Locus
These are genes that occupy corresponding loci on homologous chromosomes that affect the same trait, but in a different way.
Alleles
If the genes on the same locus that are controlling the same trait are different, then they are called “heterozygous”.
True
If the genes in the same locus are controlling a trait in the same way, then they are homozygous.
True.
Having two different genes for a particular characteristic.
Heterozygous
Having identical genes for a particular trait.
Homozygous
The trait that appears when the chromosome is heterozygous.
Dominant trait
The allele of a gene that suppresses the expression of the other allele.
Dominant
The trait that only appears when the chromosome is homozygous. It is usually masked by a dominant allele.
Recessive
The genetic makeup of an organism.
Genotype
The combination of alleles in an individual.
Genotype
The manifestation of the genotype.
Phenotype
Any behavioral, biochemical, morphological, or physiological manifestation of the genotype.
Phenotype
The genotype of an organism can change due to different environmental factors. [T/F]
False.
The genotype of an organism is fixed upon conception and expressed until death.
Other than heredity, this also causes the variation and affects the phenotypic expressions of quantitative traits.
Environment
This is the type of gene action where the phenotypic expression of one gene does not necessarily add to the phenotypic expression of the other.
Nonadditive Gene Action
An interaction of genes where one suppresses the expression of its allele.
Dominance
A form of dominance where heterozygous and homozygous dominant genotypes have the same phenotypic expression.
Complete dominance
The form of dominance where the dominance is absent and the offspring does not resemble any of its parents.
Incomplete / Partial Dominance
The form of dominance that is exhibited when a black chicken and a white chicken has an offspring with checkered plumage.
Codominance
The form of dominance that is exhibited when the heterozygote is considered more valuable than the homozygote.
Overdominance
An interaction among genes at different loci such that the expression of genes at one locus depends on the alleles present at one or more loci.
Epistasis
Type of gene action where the one gene contributed to the phenotypic expression of another gene.
Additive gene action
The phenotypic expression of an individual will become more intensive if there are more genes that contributed to it. [T/F]
True
The person behind the Mendelian Inheritance.
Gregor Mendel
The collective term for the laws that describe how the hereditary material is passed on from parent to offspring as evidenced by the physical appearance of the offspring.
The Mendelian Inheritance
Which law under the Mendelian Inheritance can be illustrated by the monohybrid cross?
Law of Independent Segregation
A cross between homozygous individuals that are different from each other at one gene locus.
Monohybrid cross
If a black cattle (Pp) is bred with a red cattle (pp), is it possible for them to have a red offspring, given that black (P) is dominant to red (p)?
Yes
This law states that genes from different characters are inherited independently of the other pairs.
Laws of Independent Assortment
The law that can be best illustrated using the dihybrid cross.
The Law of Independent Assortment
A cross between two homozygous individuals that are different from each other at two gene loci.
Dihybrid cross
The application of the principles of animal genetics with the goal of improvement of animals.
Animal Breeding
The purposeful manipulation of the genetic constitution of animals, which determines the expression of their inherent characteristics resulting in desired genetic improvement.
Animal Breeding
Father of Modern Scientific Animal Breeding and Genetics
Jay Laurence Lush
He advocated for quantitative statistics and genetic information in animal breeding, instead of the subjective appearance of the animal.
What is the name of the book that is authored by Jay Laurence Lush that greatly influenced animal breeding around the world?
Animal Breeding Plans
The Founder of Animal Breeding
Robert Bakewell
Who bred the following animals:
• Leicestershire longhorn cattle
• Leicestershire sheep
• Shire horse
Robert Bakewell
Refers to the mating of relative individuals
Inbreeding
It is defined as the mating of animals to produce its kind, or simply defined as procreation.
Breeding
The offspring tend to be more homozygous when they are inbred. True or False?
True
The offspring tend to be more homozygous when they are inbred. True or False?
True