Living Organisms Basic Needs & Survival

What Do Living Things Need to Survive?

There are five basic needs of living things. So, what do all living things need? Sunlight, water, air, habitat, and food are the basic needs of all living things. Without one or more of these living things will not be able to survive. These needs also extend to humans; without these five essential resources, we would perish. What makes sunlight, water, air, habitat, and food so important for living things?

Sunlight

Sunlight is one of the most important needs of living things. It provides energy for living organisms such as plants and warms the Earth's surface so that it is hospitable for the living organisms living there. Plants require sunlight to create energy through photosynthesis which converts sunlight into chemical energy. Plants are living organisms that provide a food source for many other living organisms. Some living organisms such as mammals and birds can maintain their own body temperatures, but others, such as reptiles, require sunlight to keep themselves functioning. The amount of sunlight that is needed for survival differs between species. Some living organisms require a lot of light, while others require almost none. So, do all living organisms need sunlight? The short answer is yes. Not all living organisms need sunlight as a food source, but they require it for its warmth.

The process of photosynthesis requires sunlight.

Water

For cells to function correctly, water is required. All living things rely on properly functioning cells for survival. Some living organisms, such as fish and whales, spend their entire lives in the water. No matter where living organisms live, they require water to survive. Seventy percent of the Earth's surface is covered by water, but that doesn't mean water is always easily accessible. Some living organisms have had to adapt to environments with little water, such as deserts.

Plants do not have mouths that they use to consume water; instead, they absorb water through their leaves and roots. A lack of water will result in the wilting of the plant and its eventual death. A turgid plant is a plant that is upright and rigid, showing that it has had enough water. Along with plants, living organisms such as bacteria also require water to transport energy/nutrients to cells.

Air

Air is composed of several different gases. Most living organisms use air for respiration is composed of oxygen, nitrogen, carbon dioxide, and small amounts of other gases. Some living organisms, like humans, require oxygen for survival, and plants use carbon dioxide for respiration and release oxygen back into the atmosphere. Even living organisms that live in the water require air.

Air can also be found in surprising places, such as soil. In the soil, it aids in the process of breaking down dead organisms into organic material; this is known as decomposition. Living organisms that break down these dead organisms into reusable organic material are decomposers. Decomposers are large contributors to the health of the soil by supplying nutrients, making it a healthy place for plants to live and grow.

Along with sunlight, air helps to provide the Earth with warmth, and the atmosphere acts like a greenhouse. The atmosphere is composed of air and helps to trap the heat from the sun next to the Earth's surface. The Earth needs to be kept warm for living organisms to survive, but it could cause damage if it becomes too warm.

Habitat

An organism's habitat is also called its home or environment. The habitat where an organism lives provides the organism with safety and shelter. Habitats vary greatly between organisms; they may be very large or small. Each habitat provides everything that is required for survival. An important part of the habitat is its temperature. The temperature required by different living organisms varies. As previously mentioned, some organisms can maintain their own body temperature, but they still require the external temperature to be maintained. Some living organisms rely on external temperature to function properly and survive. Therefore there are ideal temperatures for different habitats. Processes such as metabolism and respiration depend on body temperature. An example of an organism that requires warmer temperatures would be turtles. Turtles cannot maintain their own internal body temperatures and require a warm habitat.

Reptiles depend on external temperature to maintain internal body temperatures.

Food

Food provides essential nutrients necessary for survival. Important processes, including brain function, growth, and cellular function, require certain nutrients provided by food. Plants gain nutrients from the soil where they grow, while other organisms gain nutrients by consuming food. The quality of food that an organism eats is important for the health of the organism. For humans, it is healthiest to consume foods filled with nutrients such as leafy green vegetables, fruits, and other non-processed foods. Relying on a diet purely made of foods like potato chips and pasta can have negative effects on how the body functions. Therefore, the quality of food that is consumed is vital for the organism's overall health.

Lesson Summary

Living organisms show the characteristics of being alive. These characteristics include having a specific body structure, requiring energy, being adaptable to change, having a response to stimuli, and can die, reproduce, metabolize, grow, and move. Living organisms require five basic needs: sunlight, water, air, habitat, and food.

Sunlight is converted into energy in plants through the process of photosynthesis. Water covers seventy percent of the Earth's surface and is required for many different processes in the body. Some animals can survive with little water, while others spend their entire lives in water. Plants that are rigid and upright are considered to be turgid and have had a healthy amount of water. Air is composed of different gases and is needed by organisms both on land and in the water. Air can be found in surprising places like the soil, where decomposers break down dead organisms into reusable organic materials through the process of decomposition. The habitat of an organism is also known as its home or environment. The temperature of the habitat is important and varies depending on the needs of the organism. Food provides essential nutrients that are necessary for the survival of the organism. It is important to consume nutrient-rich and healthy food.