Teachers, before instructing students on the specifics of reproduction as a characteristic of life, try asking students what is needed in order for a species to survive. Let them discuss this question and sooner or later they will (hopefully) come up with reproduction as an answer. Explain to students that there are some characteristics of life that are characteristics that living things actively participate in. Reproduction is one of them. Acquiring materials and energy is another. The other characteristics of life are sometimes done without the knowledge of the organism, such as homeostasis and without any active effort on the part of the organism.
Review with your students the characteristics of life listed below that living things actively participate in.
Acquiring Materials and Energy
In order for an organism to survive, it must at the minimum be able to find nourishment and other items from the environment that can be converted into energy. They use this energy to perform functions that sustain life. Discuss various ways that living things may acquire energy and materials such as foraging for food, vitamin absorption through sunlight. Ask students to discuss various ways that the organisms listed below might acquire materials and energy.
- humans-Some examples may include foraging or hunting for food, breathing in oxygen and absorption of sunlight.
- trees- A good way to explain how trees actively seek to acquire energy is to take students outdoors and show them how trees grow toward the sunlight.
- slugs- Shed light on slugs acquiring materials by discussing how they search fro empty shells to make into their homes.
- birds- Discuss various methods of birds building their nests and acquiring food for themselves and their young.
Discuss reproduction with your students as a means to perpetuate the life of the species. Introduce your students to the various methods of reproduction listed below, then ask them to complete the activity in the next section.
Sexual: Requires a male and female of the species to participate in bringing together a sperm cell and an egg cell to create a new living being. This form of reproduction combines the genetics of two members of the species
Asexual: There are 3 types of asexual reproduction. They are listed and defined below. It's important to note that all forms of asexual reproduction use the genetics of one living being, therefore the offspring will be genetically similar to the parent.
- Budding-This process is common in plant species. A "bud" grows on the organism until it has grown enough to become its own independent organism.
- Regeneration- Common to invertebrates, this is the process of growing limbs, organs or other tissues to replace damaged ones.
- Fission- Also known as binary fission, this is the process of an organism dividing into two separate organisms such as in cellular division.