Semester 2 Final Exam Vocab Review Set 2: Cell Cycle, Meiosis, and Genetics Mrs. K

chromosome

condensed threads of genetic material formed from chromatin as a cell prepares to divide

gamete

egg or sperm sex cell that contains a single set of chromosomes, one from each homologous pair (haploid)

sex chromosome

one of the pair of chromosomes that determine the sex of an individual (XX- female, XY- male)

mitosis

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

meiosis

the process by which the number of chromosomes is reduced by half to form 4 haploid sex cells/gametes

trait

A characteristic that an organism can pass on to its offspring through its genes.

fertilization

Process in sexual reproduction in which male and female sex cells join to form a new cell/baby

allele

A version of a particular gene

Cancer

disorder in which some of the body's cells lose the ability to control growth and divide uncontrollably. The resulting cells that interfere with the normal function of other cells.

Carcinogen

A cancer-causing substance

stem cells

An undifferentiated cell that is capable of dividing and giving rise to one or more distinct types of differentiated cell(s).

Cell Differentiation / Specialization

The process by which stem cells acquire specific functions and structures.

Karyotype

A display of the chromosome pairs of a cell arranged by size and shape.

Haploid

sex cells/gametes having only one complete set of chromosomes. (23 chromosomes in humans)

Diploid

a body/somatic cell having two sets of chromosomes or twice the haploid number (46 chromosomes in humans)

crossing over

Process that contributes to genetic variation in which homologous chromosomes exchange portions of their chromatids during meiosis.

independent assortment

Process that contributes to genetic variation states that genes for different traits can segregate independently during the formation of gametes

S Phase (interphase of mitosis)

The synthesis phase of the cell cycle; the portion of interphase during which DNA is replicated.

The normal chromosome number in a human cell is

46

somatic cells

Any diploid cells in the body that are NOT reproductive cells

Homozygous

Having two identical alleles for a particular gene (i.e. AA or aa)

Heterozygous

having two different alleles for a trait (i.e. Aa)

Phenotype

physical characteristics/appearance of an organism (i.e. Tall)

Genotype

An organism's genetic makeup, or allele combinations.

Punnett Square

A chart that shows all the possible combinations of alleles that can result from a genetic cross

homozygous dominant

Both alleles (factors) for a trait are the same and dominant (AA)

homozygous recessive

Both alleles (factors) for a trait are the same and recessive (aa)

Pedigree

A chart or "family tree" that tracks which members of a family have a particular trait

multiple alleles

three or more forms of a gene that code for a single trait

Codominance

A condition in which both alleles for a gene are fully expressed

incomplete dominance

A pattern of inheritance in which two alleles, inherited from the parents, are neither dominant nor recessive. The resulting offspring have a phenotype that is a blending of the parental traits.

polygenic inheritance

occurs when multiple genes determine the phenotype of a trait