Chapter 13: Sexual life cycles and meiosis
Chromosome: carries genetic information in the form of genes
Genome: the haploid set of chromosomes in a gamete or micro-organism, or in each cell of a
multicellular organism. Complete set of genes.
Locus: the position of a gene or mutation on a chromosome
DNA: main constituent of chromosomes. The carrier of genetic information.
Mutation: a change in the nucleotide sequence of an organism’s DNA or in the RNA of a virus
Allele: any of the alternative versions of a gene that may produce distinguishable phenotypic
effects
Sex chromosomes: X and Y
Autosomes: all other chromosomes
Diploid cell: any cell with two chromosome sets, only diploid cells can undergo meiosis.
Meiosis: a form of cell division in which each daughter cell receives half the amount of DNA
as the parent cell. Meiosis consists of two phases, meiosis I (prophase I, metaphase I,
anaphase I, telophase I) and meiosis II. This results in 4 daughter cells with different sets of
chromosomes.
Mitosis: a form of cell division in which a parent cell duplicates all its contents (including
chromosomes) and splits to form two identical daughter cells.
Chiasma: site of crossing over
Independent assortment of chromosomes: amount of possible combinations when
chromosomes assort independently= 2^n , in which n is the haploid number.
Crossing over: occurs when two chromosomes move closer together, results in synapsis
(fusion). When the chromatids break, genetic information is exchanged and two recombinant
chromosomes are made.
Random fertilization: any sperm can fuse with any ovum (unfertilized egg)
Chapter 14: Mendel
Mendel’s hypothesis: parents pass on discrete heritable units (genes)
Character: heritable feature that varies among individuals
Trait: variant for a character
Hybridization: crossing of two true-breeding individuals
P-generation: parent generation, true-breeding parents
F1-generation: first filial generation, the hybrid offspring
F2-generation: result of allowing hybrids to self-pollinate or cross-pollinate with other
hybrids
Dominant allele: allele that is fully expressed in the phenotype of a heterozygote
Chromosome: carries genetic information in the form of genes
Genome: the haploid set of chromosomes in a gamete or micro-organism, or in each cell of a
multicellular organism. Complete set of genes.
Locus: the position of a gene or mutation on a chromosome
DNA: main constituent of chromosomes. The carrier of genetic information.
Mutation: a change in the nucleotide sequence of an organism’s DNA or in the RNA of a virus
Allele: any of the alternative versions of a gene that may produce distinguishable phenotypic
effects
Sex chromosomes: X and Y
Autosomes: all other chromosomes
Diploid cell: any cell with two chromosome sets, only diploid cells can undergo meiosis.
Meiosis: a form of cell division in which each daughter cell receives half the amount of DNA
as the parent cell. Meiosis consists of two phases, meiosis I (prophase I, metaphase I,
anaphase I, telophase I) and meiosis II. This results in 4 daughter cells with different sets of
chromosomes.
Mitosis: a form of cell division in which a parent cell duplicates all its contents (including
chromosomes) and splits to form two identical daughter cells.
Chiasma: site of crossing over
Independent assortment of chromosomes: amount of possible combinations when
chromosomes assort independently= 2^n , in which n is the haploid number.
Crossing over: occurs when two chromosomes move closer together, results in synapsis
(fusion). When the chromatids break, genetic information is exchanged and two recombinant
chromosomes are made.
Random fertilization: any sperm can fuse with any ovum (unfertilized egg)
Chapter 14: Mendel
Mendel’s hypothesis: parents pass on discrete heritable units (genes)
Character: heritable feature that varies among individuals
Trait: variant for a character
Hybridization: crossing of two true-breeding individuals
P-generation: parent generation, true-breeding parents
F1-generation: first filial generation, the hybrid offspring
F2-generation: result of allowing hybrids to self-pollinate or cross-pollinate with other
hybrids
Dominant allele: allele that is fully expressed in the phenotype of a heterozygote
