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Stage of the cell cycle during which the cell's nucleus divides


The process that occurs in sex cells (sperm & egg) by which the number of chromosomes is reduced by half


The basic unit of structure and function in living things

Cell Theory

A widely accepted explanation of the relationship between cells and living things

Selectively Permeable

A property of cell membranes that allows some substances to pass through, while others cannot


The process by which molecules move from an area of higher concentration to an area of lower concentration


The diffusion of water molecules through a selectively permeable membrane

Active Transport

The movement of materials through a cell membrane using energy

Passive Transport

The movement of materials through a cell membrane without using energy


The different forms of a gene


The passing of traits from parents to offspring


A segment of DNA on a chromosome that codes for a specific trait


The scientific study of heredity


Having two different alleles for a trait (hybrid)

Dominant Allele

An allele whose trait always shows up in the organism when the allele is present


An organism's genetic makeup, or allele combinations


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


An organism that is heterozygous for a particular trait


An organism that always produces offspring with the same form of a trait as the parent


Having two identical alleles for a trait (purebred)

Recessive Allele

An allele that is masked when a dominant allele is present


An organism's physical appearance, or visible traits

Punnett Square

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


The ability to make things look larger than they are. (Multiply magnification of eye piece by magnification of objective).


The ability to clearly distinguish the individual parts of an object. (Turn the coarse adjustment, then the fine adjustment).

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