Study Guide: Cell Cycle, Mitosis, Meiosis, and Mendelian Genetics (Chapters 7-8)

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Cell Cycle: The ordered sequence of events in the life of a cell, including growth, DNA replication, and cell division.
Phases of the Cell Cycle: Includes interphase (G1, S, G2) and the mitotic (M) phase.
Mitosis: The process by which a eukaryotic cell separates its duplicated chromosomes into two identical nuclei.
Cytokinesis: Division of the cytoplasm, resulting in two daughter cells.

Mitosis ensures equal distribution of genetic material to daughter cells.
It is essential for growth, repair, and asexual reproduction in multicellular organisms.

Checkpoints are control mechanisms that ensure the cell cycle proceeds only when certain conditions are met (e.g., DNA integrity, proper chromosome attachment).
They help prevent the division of damaged or incomplete cells.

Chromosomes are composed of DNA and proteins; they condense during cell division.
During mitosis, chromosomes align at the metaphase plate and are separated by the spindle apparatus.

Phases can be identified by chromosome appearance and spindle orientation:
- Prophase: Chromosomes condense, spindle forms.
- Metaphase: Chromosomes align at the cell's equator.
- Anaphase: Sister chromatids separate.
- Telophase: Nuclear envelopes reform around chromosomes.

Meiosis: A two-part cell division process that produces gametes (sperm and eggs) with half the chromosome number of the parent cell.
Homologous Chromosomes: Chromosome pairs, one from each parent, that are similar in shape, size, and genetic content.
Synapsis: Pairing of homologous chromosomes during meiosis I.
Crossing Over (Recombination): Exchange of genetic material between homologous chromosomes, increasing genetic diversity.
Independent Assortment: Random distribution of homologous chromosomes during meiosis I.
Reciprocal Cross: A cross in which the phenotypes of the male and female are reversed compared to a previous cross.

Reduces chromosome number by half, ensuring offspring have the correct number of chromosomes.
Generates genetic variation through crossing over and independent assortment.

Feature	Mitosis	Meiosis
Number of Divisions	1	2
Number of Daughter Cells	2	4
Genetic Identity	Identical	Unique
Chromosome Number	Diploid (2n)	Haploid (n)
Role	Growth, repair, asexual reproduction	Sexual reproduction

Gene: A unit of heredity that encodes information for a specific trait.
Allele: Different forms of a gene.
Genotype: The genetic makeup of an organism (e.g., AA, Aa, aa).
Phenotype: The observable traits of an organism.
Dominant: An allele that masks the effect of a recessive allele.
Recessive: An allele whose effect is masked by a dominant allele.
Homozygous: Having two identical alleles for a gene.
Heterozygous: Having two different alleles for a gene.
P, F1, F2 Generations: Parental, first filial, and second filial generations in genetic crosses.
Particulate Inheritance: Concept that inheritance is based on discrete units (genes) that retain their identity.
Principle of Segregation: Each individual has two alleles for each gene, which segregate during gamete formation.
Principle of Independent Assortment: Genes for different traits can segregate independently during gamete formation.

	A	a
A	AA	Aa
a	Aa	aa

Used to determine the genotype of an individual with a dominant phenotype by crossing with a homozygous recessive individual.

Be able to predict offspring genotypes and phenotypes from genetic crosses.
Interpret pedigrees to determine inheritance patterns (dominant, recessive, autosomal, sex-linked).
Understand how crossing over and independent assortment contribute to genetic variation.

Codominance: Both alleles are expressed equally in the phenotype (e.g., AB blood type).
Incomplete dominance: Heterozygotes show an intermediate phenotype.