Chromosomes

Differentiation

(biology) the structural adaptation of some body part for a particular function

Recombination

(genetics) a combining of genes or characters different from what they were in the parents

Meiosis

(genetics) cell division that produces reproductive cells in sexually reproducing organisms

Homologous chromosomes

Chromosomes with matching information

N (haploid, monoploid)

Half the number of chromosomes

2N (diploid)

The normal number of chromosomes

Gonad

a gland in which gametes (sex cells) are produced

Gamete

a mature sexual reproductive cell having a single set of unpaired chromosomes

Morula

a solid mass of blastomeres that forms when the zygote splits

Centromere

a specialized condensed region of each chromosome that appears during mitosis where the chromatids are held together to form an X shape

Mitosis

cell division in which the nucleus divides into nuclei containing the same number of chromosomes

Autosomes

chromosomes that are not directly involved in determining the sex of an individual

Gastrula

double-walled stage of the embryo resulting from invagination of the blastula

Blastula

early stage of an embryo produced by cleavage of an ovum

Non-disjunction

meiosis in which there is a failure of paired homologous chromosomes to separate

Sex chromosomes

one of the 23 pairs of chromosomes in the human, contains genes that will determine the sex of the individual

Fertilization

process in sexual reproduction in which male and female reproductive cells join to form a new cell

Interphase

stage of the cell cycle during which a cell carries out its metabolic processes and performs its functions in the body

Disjunction

the act of breaking a connection

Cleavage

the act of cleaving or splitting

Karyotype

the appearance of the chromosomal makeup of a somatic cell in an individual or species (including the number and arrangement and size and structure of the chromosomes)

Tetrad

the cardinal number that is the sum of three and one

Zygote

the cell resulting from the union of an ovum and a spermatozoon (including the organism that develops from that cell)

Telophase

the final stage of mitosis

Prophase

the first stage of mitosis

Growth

the gradual beginning or coming forth

Crossing over

the interchange of sections between pairing homologous chromosomes during the prophase of meiosis

Chromatin

the readily stainable substance of a cell nucleus consisting of DNA and RNA and various proteins

Metaphase

the second stage of mitosis

Synapsis

the side by side pairing of homologous maternal and paternal chromosomes at the start of meiosis

Specialization

the special line of work you have adopted as your career

Anaphase

the stage of meiosis or mitosis when chromosomes move toward opposite ends of the nuclear spindle

Chromosomes

threadlike structures made of DNA molecules that contain the genes

Chromatids

two identical chromosomes that split and contain the same genetic material