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Human Chromosomes

alleles = alternative versions of a gene

character = a feature that can be inherited

chromatid = a pair of identical DNA molecules after replication joined together by centromeres, two chromatids make up one chromosome.

chromatin = DNA/protein complex that makes up each chromosome

chromosomes = DNA molecules in a eukaryotic organism for holding and transmitting genetic information (insert chromosome image). Humans have 23 pairs of chromosomes for a total of 46. Two chromosomes are sex chromosomes either X Y (male) or X X (female). The other 22 pairs are autosomes.

DNA = basic molecular structure for all genetic material

diploid = having two sets of chromosomes in a cell, 2n

gametes = cells that have undergone meiosis and have half the number of chromosomes as normal cells, they can now take part in fertilization

genome = the total DNA in a cell

germ line cells = Germ line cells are unique cells that migrate early on into the body into the gonads. These are the only cells in the body that undergo meiosis to produce gametes.

heterozygous = having different alleles for a specific character or feature

homologous chromosomes = chromosomes with identical genetic material

homozygous = having an identical pair of alleles for a specific character or feature

haploid = having one set of chromosomes in a cell, n

somatic cells = They are found everywhere in the body. These cells go through mitosis cell division

trait = a certain variation of a character

zygote = result of the union of two gametes, contains the normal number of chromosomes and will pass all of its genes onto all new cells that form from it.

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