Traits, Genes, and Reproduction Basics

Traits

An organism's characteristics or features encoded into its DNA.

Gene

A segment of DNA that codes for a particular trait.

Alleles

Different versions of a gene that determine specific traits.

Homozygous

An organism that has two of the same alleles for a trait.

Heterozygous

An organism that has two different alleles for a trait.

Dominant Allele

The stronger allele that is always expressed when present.

Recessive Allele

The allele that gets masked and is only expressed when both alleles are recessive.

Genotype

The genes an organism has.

Phenotype

The traits an organism expresses.

Cell Wall

The rigid barrier made out of cellulose that surrounds plant cells.

Chloroplasts

Organelles in plant cells that produce food from sunlight.

Lysosome

The cell's stomach that breaks down food and waste.

Mitochondria

Organelles that convert energy in food into usable forms for the cell.

Endoplasmic Reticulum (ER)

The transport facility of the cell, made of folded membranes.

Golgi bodies

Packaging, sorting, and distribution centers of the cell.

Ribosomes

The protein-making factories of the cell.

Nucleus

The control center of the cell that houses chromosomes.

Prokaryotes

Simple cells without a membrane-bound nucleus, found in single-celled bacteria.

Eukaryotes

Complex cells with a membrane-bound nucleus, found in animals, plants, and fungi.

Asexual Reproduction

Reproduction where one parent produces genetically identical offspring.

Binary Fussion

A type of asexual reproduction in prokaryotes where the cell splits to form two identical cells.