Lesson 3- Principles of Genetics

What are the components of a DNA nucleotide?

A nucleotide consists of a phosphate molecule, a sugar molecule, and a base.

What is Mendel's first law of segregation?

The characteristics of an organism are controlled by pairs of alleles which separate in equal numbers into different gametes.

How many chromosomes are found in diploid cells?

Diploid cells contain a complete set of chromosomes, which is typically two copies of each chromosome.

What does a Punnett square illustrate?

A Punnett square is used to predict the genotypes and phenotypes of offspring from a genetic cross.

What is the phenotype for a true breeding tall pea plant?

The phenotype for a true breeding tall pea plant is tall.

Which bases pair together in DNA?

Adenine (A) pairs with Thymine (T), and Guanine (G) pairs with Cytosine (C).

What is the significance of the F1 generation in Mendel's experiments?

The F1 generation is the offspring of the parental (P1) generation and showcases the dominant traits.

What is the difference between homozygous and heterozygous genotypes?

Homozygous genotypes have two identical alleles for a trait, while heterozygous genotypes have two different alleles.

What is the result of mitosis?

Mitosis results in two identical daughter cells with the same number of chromosomes as the parent cell.

What defines a dihybrid cross in genetics?

A dihybrid cross examines the inheritance of two different traits simultaneously.

Punnett squares are used to determine the __________ of offspring.

genetic combinations

In a monohybrid cross, a Punnett square illustrates the inheritance of __________ trait(s).

one

The __________ generation is the parental generation in a Punnett square.

P1

When crossing two heterozygous individuals (Aa x Aa), the expected genotype ratio is __________.

1:2:1

A Punnett square can visually represent __________ and phenotypic ratios.

genotypic

The allele that masks the expression of another allele is known as the __________ allele.

dominant

The __________ allele is expressed only when two copies are present in the genotype.

recessive

In a dihybrid cross, a Punnett square shows the combinations of __________ traits.

two different

The total number of boxes in a Punnett square for a dihybrid cross is __________.

16

Punnett squares help predict the __________ outcome of genetic crosses.

possible

In a Punnett square, __________ represents the possible gametes of one parent.

one axis of the square

The letters in a Punnett square represent the __________ of alleles.

genotypes

The F2 generation in a Punnett square results from __________ the F1 generation.

crossing

Each box in a Punnett square shows a __________ combination of alleles.

possible

In a monohybrid cross, a Punnett square typically has __________ boxes.

4

The __________ in a Punnett square indicate the parents' alleles for a trait.

labels

A Punnett square can be used to predict __________ ratios.

genotypic and phenotypic

The __________ cross calculates the inheritance of one trait.

monohybrid

In a dihybrid cross, each parent has __________ different traits being examined.

two

The offspring in a Punnett square are referred to as the __________ generation.

F1