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Plants and animals have life cycles that include being born, developing into adults, reproducing, and eventually dying.

Plants and animals closely resemble their parents but not exactly.

There are differences among individual organisms of a species.

Each different organism has a life cycle that is different from other organisms.

Plants and animals may change in appearance a little or a lot as they grow.

In many species, including humans, females produce eggs and males produce sperm, plants also reproduce sexually, the egg and sperm are produced in the flowers of flowering plants. An egg and sperm unite (fertilization) to begin development of a new individual. That new individual receives genetic information from its mother (via the egg) and its father (via the sperm). Sexually produced offspring never are identical to either of their parents.

Many characteristics of an organism are inherited from the parents of the organism, but other characteristics result from an individual’s interactions with the environment. Inherited characteristics include the color of flowers and the number of limbs of an animal. Other features, such as the ability to ride a bicycle, are learned through interactions with the environment and cannot be passes on to the next generation. This infers a way to transfer genetic infomation from one generation to another.

Reproduction is a characteristic of all living systems. No individual organism lives forever. Therefore, reproduction is essential to the continuation of every species. Some organisms reproduce asexually and other organisms reproduce sexually. Genetic characteristics are passed from only one parent (asexual) or two parents (sexual) reproduction.

Every organism requires a set of instructions for specifying its traits. Heredity is the passage of these instruction from one generation to another. Heredity information is contained in genes, located in the chromosomes of each cell. Each gene carries a single unit of information. An inherited trait of an individual can be determined by one or by many genes, and a signal gene can influence more than one trait. A human cell contains many thousands of different genes.

New varieties of plants and animals have been cultivated through selective breeding and gene splicing.