Studied by 3 people
Diploid
A cell that has two sets of chromosomes. “2n” ← two copies of chromosomes.
Haploid
A cell that has one set of chromosomes. n ← one copy of chromosomes
Sex cells
Haploids, each parent will give a gamete and a new diploid cell will produced known as a zygote.
Gregor Mendel
Discoverer of genetics
Genes
traits are influenced by one or more of your genes
Homologous chromosomes
two copies or versions of the same chromosome in a diploid cell or organism.
Humans have 23 pairs of homologous chromosomes.
homologous chromosomes are the same shape and size and contain the same genes.
homozygous
when an organism has two identical alleles for a given trait.
heterozygous
when an organism has two different alleles for a given trait
phenotype
physical appearance of an organism
genotype
which alleles the organism processes
dominant allele
has a capital letter
recessive allele
lowercase of the same letter of the dominant.
P generation
P or parent is the first generation
F1
F1 or first filial is the offspring of the P generation
F2
The next generation or the grandchildren are the F2 generation
Three principles of genetics
The Law of dominance, the law of segregation, and the law of independent assortment.
The law of dominance
Some alleles are dominant over others and the dominant allele will be expressed in an organism
monohybrid cross
when two individuals are crosses and one gene is being studied. Use a punnett square.
The law of segregation
The physical expression of a trait is known as the __________.
phenotype.
The genetic makeup of an organism is referred to as its __________.
genotype.
A __________ is an observable feature or characteristic of an organism, such as color or height.
trait.
In genetics, the __________ is the study of how traits are passed from one generation to the next.
inheritance.
An organism that has two identical alleles for a trait is described as __________.
homozygous.
When an organism has two different alleles for a trait, it is called __________.
heterozygous.
The __________ generation consists of the parent organisms in a genetic cross.
P (parent).
The __________ generation is the first generation of offspring from the parental generation.
F1 (first filial).
The __________ generation is the offspring of the F1 generation.
F2.
Alleles that mask the expression of other alleles are called __________ alleles.
dominant.
Alleles that are hidden by the presence of dominant alleles are known as __________ alleles.
recessive.
An example of a __________ cross is when two individuals are crossed, and one trait is being examined using a Punnett square.
monohybrid.
Each allele for a trait segregates into different gametes during __________ in meiosis.
gamete formation.
The __________ law states that alleles for different traits segregate independently of one another.
law of independent assortment.
The __________ law states that only one of the alleles in a pair is passed on to the offspring.
law of segregation.
What is heredity?
The passing of traits from parents to offspring.
What is a allele?
Different forms of a gene that can exist for a particular trait.
What does it mean for an allele to be dominant?
It masks the effect of a recessive allele when present.
What is a recessive allele?
It is an allele that is masked by the presence of a dominant allele.
What is a phenotype?
The observable physical or biochemical characteristics of an organism.
What is a genotype?
The genetic constitution or makeup of an organism.
What is the purpose of a Punnett square?
To predict the genotypes and phenotypes of offspring from a genetic cross.
What is Mendel's Law of Segregation?
The principle that during the formation of gametes, the two alleles for a trait separate.
What is a monohybrid cross?
A genetic cross between parents that differ in one trait.
What does F2 generation represent?
The second generation, offspring of the F1 generation.
What is a test cross?
A cross between an individual with an unknown genotype and a homozygous recessive individual.
What is a dihybrid cross?
A genetic cross that examines two traits.
What are linked genes?
Genes located on the same chromosome that tend to be inherited together.
What is the difference between homozygous and heterozygous?
Homozygous has two identical alleles; heterozygous has two different alleles.
What is a pedigree chart?
A diagram that shows the occurrence of a genetic trait in several generations of a family.
