Unit 3 List 2 DNA and Heredity MCA Flashcards
Centromere
the region of a chromosome to which the microtubules of the spindle attach, via the kinetochore, during cell division.
Allele
one of two or more alternative forms of a gene that arise by mutation and are found at the same place on a chromosome.
Chromatid
each of the two threadlike strands into which a chromosome divides longitudinally during cell division. Each contains a double helix of DNA.
Chromosome
a threadlike structure of nucleic acids and protein found in the nucleus of most living cells, carrying genetic information in the form of genes.
Codon (chart)
A codon chart, sometimes called a genetic code, shows all of the possible three letter combinations of mRNA nucleotides, and for which amino acid each combination codes for.
Crossing Over
a cellular process that happens during meiosis when chromosomes of the same type are lined up
Daughter Cell
the cells that are formed after cell division
Deletion
A type of genetic change that involves the absence of a segment of DNA.
Diploid
the presence of two complete sets of chromosomes in an organism’s cells, with each parent contributing a chromosome to each pair.
DNA
the molecule that carries genetic information for the development and functioning of an organism
Fertilization
the union of two gametes. During fertilization, sperm and egg fuse
Frameshift
a genetic mutation caused by a deletion or insertion in a DNA sequence that shifts the way the sequence is read
Gamete
a reproductive cell of an animal or plan
Gene Mutation
a change to a gene’s DNA sequence to produce something different.
Gene
The basic unit of heredity passed from parent to child
Genetic Code
A set of rules that defines how the information encoded in DNA and RNA sequences is translated into proteins
Genetic Variation
the difference in DNA among individuals or the differences between populations among the same species
Haploid
a cell that contains a single set of chromosomes.
Homologous Chromosome
a set of one maternal and one paternal chromosome that pair up with each other inside a cell during fertilization.
Independent Assortment
the alleles of two (or more) different genes get sorted into gametes independently of one another.
Insertion
the addition of one or more nucleotide base pairs into a DNA sequence
Meiosis
a type of cell division that reduces the number of chromosomes in the parent cell by half and produces four gamete cells.
Meiosis I
the number of cells is doubled but the number of chromosomes is not
Meiosis II
a mitotic division of each of the haploid cells produced in meiosis I
Monosomy
the condition in which only one chromosome from a pair is present in cells rather than the two copies usually found in diploid cells.
Mutagen
a chemical or physical agent capable of inducing changes in DNA called mutations
Mutation
an alteration in the nucleic acid sequence of the genome of an organism, virus, or extrachromosomal DNA.
Nondisjunction
a pair of homologous chromosomes has failed to separate or segregate at anaphase so that both chromosomes of the pair pass to the same daughter cell.
Offspring
the young creation of living organisms, produced either by sexual or asexual reproduction
Parent Cell
A cell that is the source of other cells, as a cell that divides to produce two or more daughter cells, or a stem cell that is a progenitor of other cells or is the first in a line of developing cells
Replication
the process by which the genome’s DNA is copied in cells
Point Mutation
A genetic alteration caused by the substitution of a single nucleotide for another nucleotide
Sexual Reproduction
the production of new organisms by the combination of genetic information of two individuals of different sexes
Somatic Cell
the cells in the body other than sperm and egg cells
Trisomy
The presence of an extra chromosome in some or all of the body’s cells
Substituion
a type of mutation in which one nucleotide is replaced by a different nucleotide
Trait
a specific characteristic of an individual
