ap bio unit 5 heredity

may 5th

Meiosis 1

Involves homologous chromosomes.

Prophase 1

Chromatin condenses; sister chromatids/homologous chromosomes align; crossing over happens, allowing exchange of genetic material between non-sister chromatids, which increases genetic diversity among the gametes.

Metaphase 1

Homologous chromosomes align on the metaphase plate; independent assortment occurs during metaphase 1, where the orientation of each homologous chromosome pair is random.

Anaphase 1

Homologous chromosomes separate to opposite poles.

Telophase 1

Nuclear envelope forms around the haploid daughter cells.

Diploid vs. Haploid

Diploid cells have 2 complete sets of chromosomes (2n); haploid cells contain only one complete set of chromosomes (n), crucial for sexual reproduction.

Meiosis 2

The second division of meiosis, which includes prophase 2, metaphase 2, anaphase 2, and telophase 2.

Prophase 2

Chromatin condenses; sister chromatids align.

Metaphase 2

Sister chromatids are aligned in the metaphase plate, ready for separation during anaphase.

Anaphase 2

Sister chromatids are pulled apart and move toward the opposite side.

Telophase 2

Nuclear envelope forms around the haploid daughter cells, resulting in two distinct nuclei in each of the daughter cells.

Meiosis vs Mitosis

Meiosis reduces the chromosome number by half, producing four genetically diverse haploid cells; Mitosis results in two identical diploid daughter cells.

Inheritance Patterns

Ways in which traits are passed down from parents to offspring, influenced by dominant and recessive alleles.

Chromosomal Inheritance

Concept that genes are located on chromosomes and are passed from parent to offspring during reproduction.

Genetic Variation

Crossing over = non-sister chromatids exchange genetic information; independent assortment = random distribution of maternal and paternal chromosomes.

Law of Segregation

Homologous chromosomes will separate and move apart to opposite poles (alleles are segregated).

Random Fertilization

Any sperm can fuse with any egg, leading to variety in offspring.

Human Genetic Disorders

Examples include sickle cell disease, tay sachs disease, and huntingtons disease.

Autosomal Dominant

Trait appears in every generation; affected individuals have at least one affected parent.

Autosomal Recessive

Affected individuals appear in the offspring of unaffected parents, indicating that both parents might be carriers.

X Linked Dominant

Traits affect all daughters of an affected father; sons are not affected.

X Linked Recessive

Fathers make daughters carriers; sons are not made into carriers.

Y Linked Traits

Only affects males; if a male has a trait he will pass it on to all of his sons.