37 cards
Define **allele**.
An **allele** is a variant form of a gene. Different alleles can result in different traits.
What is **homozygosity**?
Homozygosity occurs when an individual has two identical alleles for a particular gene.
What does **heterozygous** mean?
An individual is **heterozygous** for a gene if they have two different alleles at a gene locus.
Describe **dominant** allele.
A **dominant** allele is one that expresses its trait even when only one copy is present in a genotype.
What is a **recessive** allele?
A **recessive** allele is one that only expresses its trait when two copies are present in a genotype.
What is **codominance**?
**Codominance** occurs when both alleles in a heterozygote are fully expressed, resulting in a phenotype that displays both traits.
Explain **incomplete dominance**.
**Incomplete dominance** is a genetic situation where the phenotype of the heterozygote is intermediate between the two homozygotes.
Define **genotype**.
A **genotype** is the genetic makeup of an organism, represented by the alleles it possesses.
Define **phenotype**.
A **phenotype** is the observable traits or characteristics of an organism, resulting from the interaction of its genotype with the environment.
What is **Mendel's Law of Segregation**?
Mendel's Law of Segregation states that during the formation of gametes, the alleles for a trait separate, so each gamete carries only one allele for each trait.
What is a **gene**?
A **gene** is a segment of DNA that contains the instructions for the synthesis of a specific protein or RNA molecule.
Describe **Mendel's Law of Independent Assortment**.
Mendel's Law of Independent Assortment states that genes for different traits can segregate independently during the formation of gametes.
What is a **Punnett Square** used for?
A **Punnett Square** is a diagram used to predict the genotypes and phenotypes of offspring from a genetic cross.
What is **linkage** in genetics?
In genetics, **linkage** refers to the tendency of genes located close together on a chromosome to be inherited together.
Define **genetic recombination**.
**Genetic recombination** is the process by which genetic material is rearranged during meiosis, resulting in new allele combinations.
What is a **test cross**?
A **test cross** is a genetic cross between an individual with an unknown genotype and a homozygous recessive individual to determine the unknown genotype.
What is **epistasis**?
**Epistasis** is an interaction between genes in which one gene masks or interferes with the expression of another.
Define **pleiotropy**.
**Pleiotropy** occurs when one gene influences multiple phenotypic traits.
What is **polygenic inheritance**?
**Polygenic inheritance** involves multiple genes contributing to a single phenotypic trait, often resulting in continuous variation.
What is the **Hardy-Weinberg Principle**?
The **Hardy-Weinberg Principle** states that allele and genotype frequencies will remain constant in a population from generation to generation in the absence of evolutionary influences.
State the Hardy-Weinberg equation.
The Hardy-Weinberg equation is $p^2 + 2pq + q^2 = 1$, where $p$ and $q$ represent the frequencies of the alleles.
What is **genetic drift**?
**Genetic drift** is the change in the frequency of an allele in a population due to random sampling of organisms.
Define **bottleneck effect**.
The **bottleneck effect** is a sharp reduction in the size of a population due to environmental events or human activities, leading to a loss of genetic diversity.
What is the **founder effect**?
The **founder effect** occurs when a small group from a population establishes a new population with a different allele frequency than the original population.
Describe **gene flow**.
**Gene flow** is the transfer of genetic material between separate populations, leading to changes in allele frequencies.
What is **mutation**?
A **mutation** is a change in the DNA sequence that can lead to genetic diversity and potentially result in new traits.
What is **natural selection**?
**Natural selection** is the process where organisms with favorable traits are more likely to survive and reproduce, leading to evolutionary changes.
Define **sexual selection**.
**Sexual selection** is a form of natural selection where individuals with certain characteristics are more likely to attract mates and reproduce.
What are **sex-linked traits**?
Traits that are determined by genes located on sex chromosomes, often resulting in different patterns of inheritance in males and females.
Explain **X-inactivation**.
**X-inactivation** is the process by which one of the two X chromosomes in females is randomly inactivated, leading to dosage compensation.
What is a **karyotype**?
A **karyotype** is a visual representation of an individual's chromosomes, arranged by size and shape.
Define **genome**.
A **genome** is the complete set of genetic material present in an organism or cell.
What is **genetic engineering**?
**Genetic engineering** is the manipulation of an organism's genome using biotechnology to create desired traits.
Describe the process of **gene cloning**.
**Gene cloning** involves isolating a specific gene and making multiple copies of it, often using bacterial plasmids.
What is **CRISPR-Cas9**?
**CRISPR-Cas9** is a genome editing tool that allows for precise modifications to DNA sequences in cells.
What is the role of **RNA interference** (RNAi)?
**RNA interference** (RNAi) is a biological process where RNA molecules inhibit gene expression by neutralizing targeted mRNA molecules.
Define **transgenic organism**.
A **transgenic organism** is an organism that has been genetically modified to contain DNA from a different species.
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