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What is Mitosis?

Asexual reproduction that preserves the chromosome number, resulting in 1 diploid cell dividing into 2 diploid cells. Phases include Prophase, Metaphase, Anaphase, Telophase.

What process describes the division of one diploid cell into four haploid cells?

Meiosis.

What creates genetic variation during Meiosis?

Crossing over, independent assortment, and random fertilization.

What is the term for a normal chromosome number?

Euploid.

What does Aneuploid refer to?

An abnormal chromosome number (e.g., monosomy, trisomy).

What is Trisomy 21?

A type of aneuploidy resulting in Down syndrome.

What is Turner Syndrome?

A chromosomal abnormality with the genotype XO.

What genetic condition is characterized by the genotype XXY?

Klinefelter Syndrome.

What is Heredity?

The passing of traits from parents to offspring.

What is a Locus?

The specific location of a gene on a chromosome.

What is an Allele?

A version or variant form of a gene.

Define Genotype.

The genetic makeup of an organism (e.g., TT, Tt, tt).

What is a Phenotype?

The observable physical or biochemical trait of an organism (e.g., tall, dwarf).

What does it mean to be Homozygous?

Having two identical alleles for a particular gene (e.g., TT, tt).

What does Heterozygous mean?

Having two different alleles for a particular gene (e.g., Tt).

What does the Law of Dominance state?

A dominant allele will mask the expression of a recessive allele.

What is stated by the Law of Segregation?

Alleles for each gene separate during gamete formation, so each gamete receives only one allele.

What does the Law of Independent Assortment state?

Genes located on different chromosomes assort independently of one another during gamete formation.

What is the F2 Genotypic Ratio in a Monohybrid Cross?

1:2:1.

What is the F2 Phenotypic Ratio in a Monohybrid Cross?

3:1.

What is the F2 Phenotypic Ratio in a Dihybrid Cross?

9:3:3:1.

What is Incomplete Dominance?

A genetic inheritance pattern where the heterozygous phenotype is a blend of the two homozygous phenotypes.

What is Co-dominance?

A genetic inheritance pattern where both alleles are expressed equally in the heterozygote.

What are Multiple Alleles / Polygenic Traits?

Traits influenced by multiple genes or more than two alleles for a single gene.

What is Pleiotropy?

When a single gene affects multiple seemingly unrelated traits.

What is Sex-linked Inheritance?

Inheritance of traits carried on sex chromosomes, typically X-linked traits.

What is DNA?

A double-stranded helix with a sugar-phosphate backbone that stores genetic information.

What is RNA?

A single-stranded nucleic acid that carries instructions from DNA to make proteins.

What is a nucleotide?

The basic building block of DNA and RNA.

What is the purpose of DNA Replication?

To copy DNA for cell division.

What is Semi-conservative Replication?

A model of DNA replication where each new DNA molecule consists of one old strand and one newly synthesized strand.

What does Helicase do?

An enzyme responsible for unwinding the DNA double helix during replication.

What is the role of Primase?

An enzyme that synthesizes short RNA primers for DNA polymerase.

What does DNA Polymerase III do?

The primary enzyme responsible for adding new nucleotides during replication.

What is the Leading Strand?

The DNA strand synthesized continuously in the 5' to 3' direction during replication.

What is the Lagging Strand?

The DNA strand synthesized discontinuously in short segments called Okazaki fragments.

What is DNA Polymerase I responsible for?

Replacing RNA primers with DNA nucleotides during replication.

What does Ligase do during DNA replication?

Seals the gaps between Okazaki fragments by forming phosphodiester bonds.

What is the function of Telomerase?

Maintains the ends of chromosomes by adding repetitive DNA sequences.

What is Mismatch Repair?

A DNA repair mechanism that corrects errors not fixed by DNA polymerase proofreading.

What is Nucleotide Excision Repair?

A DNA repair mechanism that removes and replaces damaged nucleotides.

What is a Point Mutation?

A mutation involving a change in a single base pair in the DNA sequence.

What is the Central Dogma?

The concept that genetic information flows from DNA to RNA to Protein.

What occurs during Transcription?

DNA is used as a template to synthesize mRNA via RNA polymerase.

What is RNA Polymerase?

The enzyme responsible for synthesizing mRNA from a DNA template.

What are Introns?

Non-coding sequences within a gene that are removed from the mRNA transcript.

What are Exons?

Coding sequences within a gene that are expressed in the final mRNA molecule.

What involves mRNA post-transcriptional modifications?

The addition of a 5' cap and a 3' poly-A tail to the mRNA molecule.

What happens during Translation?

mRNA's genetic code is read by ribosomes and tRNA to synthesize a polypeptide chain.

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