Cell Reproduction, Meiosis, Heredity, and Evolution Flashcards

Vocabulary flashcards covering the cell cycle, meiosis, Mendelian genetics, and the principles of evolution based on the provided lecture notes.

Diploid cell

A cell containing two sets of chromosomes, which is twice the number found in a haploid cell.

DNA Compaction Levels

The order of DNA organization from least to most compact: Nucleosome, $30\text{-nm}$ fibers, Radial loop domains, Heterochromatin, and Chromosome.

Alleles

Different forms of the same gene.

G0 phase

The phase of the cell cycle where mature neurons are most likely to be found.

S phase

The specific stage of the cell cycle during which DNA is duplicated.

Septum

A structure whose formation is directed by $FtsZ$ proteins and which eventually forms the new cell walls of daughter cells.

Closed mitosis

A type of cell division performed by some protists that does not require the complete breakdown of the nuclear envelope.

$G_2$ checkpoint prerequisite

The main requirement for clearance at this stage of the cell cycle is accurate DNA replication.

Independent Assortment combinations

The number of unique chromosome combinations generated if an organism has $n=8$ is calculated as $2^8$ (or $256$).

Chiasmata

The structures where homologous chromosomes are connected at metaphase I.

Meiotic interkinesis

The phase of meiosis that is missing the S phase found in mitotic interphase.

Alternation of generations

The type of life cycle that features both a haploid and a diploid multicellular stage.

Germ cells

Cells that are capable of undergoing both meiosis and mitosis.

Phenotype

The observable traits expressed by an organism.

Character

A heritable feature, such as flower color, which may have different variations or traits.

Incomplete dominance

The inheritance pattern describing the presence of red, white, and pink flowers in the $F_2$ offspring of snapdragons.

Multiple alleles

The genetic determination pattern seen in rabbit coat color, involving variations like Wild Type, Chinchilla, Himalayan, and albino.

X-linked traits

The inheritance pattern associated with Type A hemophilia and white-eye color in specific crosses.

Homozygous

The condition in which an individual has two identical alleles for a specific trait, which is required briefly to observe a recessive trait.

Natural Selection

The scientific concept of evolution independently discovered by Charles Darwin and Alfred Wallace.

Homologous structures

Organs or skeletal elements, such as a whale's flipper, a bat's wing, and a cheetah's forelimb, that share the same overall construction.

Convergent evolution

The process by which different species independently evolve similar traits.

Allopatric speciation

The type of speciation that may occur after geographic separation, such as a lake forming and dividing small mammal populations.

Behavioral isolation

A type of reproductive isolation that occurs if two species living in the same area have different mating rituals.

Reinforcement

The term used to describe the continued divergence of species based on the low fitness of hybrid offspring.

Adaptive Radiation

A process where a population of one species disperses throughout an area and each group finds a distinct niche.