Chapter I: Intro to Genetics Flashcards
Meiosis
Associated with sexual reproduction
Promotes variation
Mitosis
Produces genetic identity
Allows for growth and repair without disrupting genetic continuity
Downside: clonal aspect
Diploid (2n)
Condition where chromosomes occur in pairs (2n)
Homologous/homologs
Chromosomes that have the same size, centrometric position, DNA content and gene loci but different alleles at a locus
Chromosomes that synapse or pair during meiosis
Metacentric chromosome
Chromosome that has a centrally located centromere
Submetacentric chromosome
A chromosome with the centromere placed so that one arm of the chromosome is slightly longer than the other.
Telocentric chromosome
Chromosome in which the centromere is located at its very end.
Locus (pl. loci)
The site or place on a chromosome where a particular gene is located.
Genotype
The allelic or genetic constitution of an organism
Allelic make up of a locus (homozygous and heterozygous)
Homozygous
Have identical alleles for a gene
Heterozygous
Different alleles at one or more loci
Phenotype
The overt appearance of a genetically controlled trait
Dominant phenotype
An allele that overrides the potential genetic expression of a recessive allele
Recessive phenotype
An allele that whose potential genetic expression is overridden by a dominant allele
What phases does the interphase consists of?
G1 -> S -> G2
S phase (synthesis phase)
Phase where the replication of DNA occurs specifically
Haploid (n)
Organism having one member of each pair of homologous chromosomes
Chromatid
One of the longitudinal subunits of a replicated chromosome
Chromosomes
A DNA molecule complexed with RNA and proteins to form a thread like structure containing genetic information arranged in linear sequence
Chromomere
A coiled, condensed region of a chromosome, most easily visualized during cell division
Centromere
Specialized chromosomal region at which sister chromatids remain attached after replication and the site to which spindle fibers attach to the chromosome during cell division
Centriole
An organelle that serves as a foci for the spindles in cell division
Hemizygous
Having a gene present in a single dose in an otherwise diploid cell. Usually applied to the genes on the X chromosome in heterogametic males.
Heterogametic sex
The sex that produces gametes containing unlike sex chromosomes, ex: males
Homogametic sex
Sex that produces gametes that do not differ with respect to sex-chromosome content, ex: female
