haile all chapters Cell Division and Genetics

Flashcards covering key concepts and vocabulary related to cell division and genetics, including definitions and important processes.

Chromosome

Structures made of DNA tightly coiled around histone proteins, carrying genetic information.

Somatic Cells

Any cells of the body, except for gametes, are typically diploid (2n). Diploid body cells that divide by mitosis.

Gametes

Reproductive (sex) cells that transmit genes from one generation to the next. Haploid reproductive cells are produced by meiosis.

Meiosis

A type of cell division that reduces the number of chromosomes in the parent cell by half to produce four unique haploid daughter cells, essential for sexual reproduction.

Mitosis

Process that produces two genetically identical diploid somatic cells for growth, repair, and asexual reproduction.

Interphase

The longest phase of the cell cycle where the cell grows and copies its chromosomes.

Cytokinesis

The process of cell division involves the cytoplasm dividing to form two daughter cells.

Binary Fission

A form of asexual reproduction where a parent cell divides into two new cells, as seen in bacteria.

Cyclins

Proteins that cyclically fluctuate in concentration, important for cell cycle regulation.

Cdk-cyclin complex

MPF (Maturation-Promoting Factor) which triggers passage from G2 into M phase.

G1 Checkpoint

Control point that checks cell size, nutrients, growth factors, and DNA damage.

Benign Tumors

Abnormal cells that remain at the original site and do not invade.

Malignant Tumors

Cancer cells that invade nearby tissue or spread to other parts of the body.

Allele

Alternative versions of a gene that account for variations in characters.

Dominant Allele

Allele fully expressed in the phenotype when present in one or two copies.

Recessive Allele

Allele whose effect shows only when two copies are present; masked by dominant.

Punnett Square

Diagram predicting genetic cross results by showing all possible allele combinations.

Homozygous

Having two identical alleles for a gene.

Heterozygous

Having two different alleles for a gene.

Law of Segregation

Two alleles for a heritable character segregate during gamete formation and end up in different gametes.

Crossing Over

Exchange of genetic material between non-sister chromatids during Prophase I of meiosis.

Genetic Sex

Sex determined by sex chromosome composition such as XX or XY.

Phenotypic Sex

Observable physical characteristics of sex influenced by genes, hormones, and environment.

X Chromosome Inactivation

Process where one X chromosome in each female somatic cell is randomly inactivated.

Recombination Frequency

Proportional to physical distance between genes in a linkage map.

Aneuploidy

The presence of an abnormal number of chromosomes in a zygote, such as monosomy or trisomy.

Monosomy

Form of aneuploidy with only one copy of a chromosome in a diploid cell.

Polyploidy

Condition in which an organism has more than two complete sets of chromosomes.

Law of Independent Assortment

Two or more genes sort independently during gamete formation.

Phenotype

The organism’s observable traits are based on the inherited genotype.

Genotype

The genetic makeup of an organism, represented by alleles.It determines the potential traits an organism can express, influencing its phenotype.

Testcross

A cross is used to determine the genotype of an organism displaying a dominant trait.

Chromosome Theory of Inheritance

The theory that chromosomes are the basis of genetic inheritance

Linked Genes

Genes that are located near each other on the same chromosome and tend to be inherited together

Sex Chromosomes

A pair of chromosomes that determine biological sex, with one allele inherited from each parent.They include X and Y chromosomes in humans.

trisomy.

a genetic disorder characterized by an extra copy of a specific chromosome, resulting in three copies instead of the usual two 

Genomic Imprinting

An epigenetic phenomenon where variations in traits depend on whether the allele is inherited from the male or female parent.

Klinefelter Syndrome (XXY)

A condition in biological males who receive an extra X chromosome, leading to various symptoms, including underdeveloped sex organs.

Cri Du Chat Syndrome

A genetic disorder caused by a partial deletion of chromosome 5, characterized by distinctive facial features and delayed development.

polygenic inheritance

is a type of inheritance where multiple genes contribute to a single trait, resulting in a range of phenotypes.

pedigrees

A diagram that shows the occurrence and appearance of phenotypes of a particular gene or organism across generations, often used to track genetic traits.

hybridization

The process of crossing two different varieties or species to produce offspring with desired traits. This technique is often used in agriculture and genetics to enhance genetic diversity.

Epistasis

is a form of gene interaction in which one gene suppresses or masks the expression of another gene, influencing the phenotypic outcome.

monohybrid cross

A hybrid of two organisms each with homozygous genotypes for opposite phenotypes of a given trait.

dihybrid cross

A hybrid of two organisms each with homozygous genotypes for different traits.This genetic cross produces offspring that are heterozygous for two traits, allowing for the analysis of independent assortment.

incomplete dominance

is a genetic phenomenon where the phenotypes of the heterozygote are intermediate between the phenotypes of the two homozygotes, resulting in a blend of traits.

codominance 

A situation in which two different alleles are expressed equally in different regions.

pleiotropy

A condition in which an organism has more than two complete sets of chromosomesthat affects multiple traits due to a single gene mutation, leading to various phenotypic outcomes.

recessive disorder

A genetic condition caused by recessive alleles, requiring two copies of the allele for the disorder to manifest.

dominant disorder

A genetic condition caused by dominant alleles, requiring only one copy of the allele for the disorder to manifest.

wild type

The phenotype most commonly observed in natural populations, typically considered the standard or reference phenotype.

mutant phenotype

A phenotype that results from a mutation in a gene, leading to a variation different from the wild type.

Drosophila melanogaster

A species of fruit fly commonly used as a model organism in genetic research and experiments.