Biol 114 Spring 2025 Week 2 (1/30) Cell Division and Heredity

Vocabulary flashcards on Cell Division and Heredity.

Genetic Heritability

Heritability of specific phenotypes is key to understanding natural selection as descent with modification.

Phenotype

Measurable traits caused by genotypes.

Genotype

Genes that code for traits.

Genome

All of the hereditary information within an individual, including non-gene stretches of DNA.

Gene Pool

All the alleles of all the genes within a population.

Genotype

All of the alleles of all the genes within an individual or may refer to a specific set of alleles of a set of genes under study.

Genes

Section of DNA found on chromosomes that encodes for a polypeptide, which, in turn, causes (directly or indirectly) a trait (phenotype), may also regulate the activity of other genes.

Locus

The location of a gene on a chromosome.

Alleles

Particular versions of a gene that occur at the same locus on homologous chromosomes.

Chromosome

A structure made of DNA and associated proteins that carries genes.

Ploidy

Refers to the number of chromosomes in a set and the number of sets of chromosomes a cell contains.

Homologous Pairs

Pairs of chromosomes, one from each parent, that have the same genes but can differ in their effects on gene expression.

Diploid

Having a homologous pair of each kind of chromosome (2n).

Haploid

Having just one copy of each kind of chromosome (1n).

Meiosis

The process of the production of gametes by halving the number of chromosomes and placing them into gametic cells.

Tetrad

Structure that forms when homologous chromosomes pair up during Prophase I of meiosis.

Non-sister chromatids

Chromatids from the parental homologs (that is, one maternal and one paternal)

Chiasma

Area where non-sister chromatids link up and exchange genetic information during meiosis.

Mutations

A change in nucleotide sequence that can be caused by environmental mutagens or replication errors.

Nondisjunction

During cell divisions in meiosis I and II, one cell ends up with both pairs of homologs of one chromosome.

Aneuploidy

Having too many or too few chromosomes.

Transformation

Bacterial cells take up DNA fragments from other cells and either incorporate into the bacterium’s DNA or may be left as a separate plasmid.

Transduction

Viral capsids attach to bacterial cells and inject their DNA, which fragments the host’s DNA.

Conjugation

Cytoplasmic tube made from cell with a plasmid to a cell without the plasmid and the plasmid is transferred.

Alternation of Generations

When many organisms alternate between sexual (haploid) and asexual (diploid) generations