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What does it mean for an organism to be homozygous at a gene locus?
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An organism is homozygous at a gene locus if it has two identical alleles for a particular gene.
Describe the relationship between genotype and phenotype.
The genotype is the genetic makeup of an organism, whereas the phenotype is the observable characteristics influenced by the genotype.
How does transcription and translation relate to gene expression?
Transcription converts DNA to RNA, and translation converts RNA to proteins, which together express the gene's function in an organism.
How do alleles differ from each other at the molecular level?
Alleles are different versions of a gene and differ due to variations in their DNA sequences.
What is a diploid organism and how does it relate to alleles?
A diploid organism has two copies of each chromosome, hence two alleles for each gene, one from each parent.
How is the phenotype of a homozygous individual expressed?
The phenotype of a homozygous individual is directly expressed by the traits of the alleles present, as both alleles are the same.
Explain how a heterozygous genotype can affect the phenotype of an organism.
In a heterozygous genotype, one allele is usually dominant and the phenotype is determined by the expression of this dominant allele.
How would you represent the genotype of an organism with two different alleles?
A genotype with two different alleles is represented as heterozygous, for example, B1/B2.
Why are proteins crucial in determining phenotypes?
Proteins, created from gene-regulated processes, perform functions and create structures that result in observable traits.
What is an example of alleles affecting mice coat color?
In mice, B1 and B2 alleles might result in different coat colors such as black or white.
What is the role of a gene in the central dogma of molecular biology?
Genes are sections of DNA that are transcribed into RNA, which is then translated into proteins, affecting phenotypes.
What determines whether an allele is dominant or recessive?
Dominance is determined by the phenotype expressed from a heterozygous genotype, where the dominant allele's traits are exhibited.
Explain the concept of dominance with a heterozygous example.
In a B1/B2 heterozygote, if the phenotype is black, B1 is dominant over B2, which is recessive.
In genetic terms, what is a locus?
A locus is a specific, fixed position on a chromosome where a particular gene or genetic marker is located.
What is an example of a phenotype that can be observed in an organism?
Examples include pea color, dog coat color, or human height.
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